Bain Capital Life Sciences Investors, LLC

SEC source: 0001193125-26-237016 · ownership.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 1,463,000

Underlying: Class A Common Stock · 1,463,000 shares

Expires 2031-05-20

F1 · kind: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F1 · price: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F2 · derivative.exercise_date: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F2 · derivative.underlying_shares: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F1 · ownership.nature: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the general partner of each of BCLSP and BCLS I Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-237016 · ownership.xml · derivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 1,463,000

Underlying: Class A Common Stock · 1,463,000 shares

Expires 2027-05-20

F1 · kind: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F1 · price: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F2 · derivative.exercise_date: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F2 · derivative.underlying_shares: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F1 · ownership.nature: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the general partner of each of BCLSP and BCLS I Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-237016 · ownership.xml · derivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 1,463,000

Underlying: Class A Common Stock · 1,463,000 shares

Expires not disclosed

F1 · kind: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F1 · price: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F2 · derivative.exercise_date: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F3 · derivative.expiration_date: The Pre-Funded Warrant does not expire.

F2 · derivative.underlying_shares: The Pre-Funded Warrant, Series A Warrant and Series B Warrant cannot be exercised for shares of the Issuer's Class A Common Stock if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's Class A Common Stock then outstanding immediately following such exercise.

F1 · ownership.nature: On May 20, 2026, BCLS I Investco, LP ("BCLS I Investco") purchased, in an underwritten public offering, a Pre-Funded Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock, as well as an accompanying Series A Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof) and an accompanying Series B Warrant to purchase 1,463,000 shares of the Issuer's Class A Common Stock (or pre-funded warrants in lieu thereof). The purchase price of each pre-funded warrant and accompanying Series A Warrant and Series B Warrant was $1.945.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the general partner of each of BCLSP and BCLS I Investco and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-198593 · ownership.xml · nonDerivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 8,448,158

F4 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.00 to $30.19, inclusive.

F5 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-198593 · ownership.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 8,504,382

F3 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.00 to $29.995, inclusive.

F5 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-198593 · ownership.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 9,396,915

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $29.00 to $29.69, inclusive.

F5 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-198593 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 10,194,048

F1 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $30.50 to $31.46, inclusive. The reporting person undertakes to provide to Heartflow, Inc., any security holder of Heartflow, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in footnotes (1) through (4) of this Form 4.

F5 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-164389 · ownership.xml · derivative · entry 5

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

BCLS Fund IV Investments GP, LLC · CIK 0002015967 · 10% owner

BCLS Fund IV Investments, L.P. · CIK 0002015454 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Common Stock · 4,145,768 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_price: Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F2 · derivative.exercise_date: Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F2 · derivative.expiration_date: Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund IV Investments, LP ("BCLS Fund IV Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the managing member of BCLS Fund IV Investments GP, LLC ("BCLS Fund IV Investments GP"), which is the general partner of BCLS Fund IV Investments. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund IV Investments. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-164389 · ownership.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

BCLS Fund IV Investments GP, LLC · CIK 0002015967 · 10% owner

BCLS Fund IV Investments, L.P. · CIK 0002015454 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Common Stock · 16,875,000 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series A-1 Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.exercise_date: Each share of the Issuer's Series A-1 Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.expiration_date: Each share of the Issuer's Series A-1 Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund IV Investments, LP ("BCLS Fund IV Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the managing member of BCLS Fund IV Investments GP, LLC ("BCLS Fund IV Investments GP"), which is the general partner of BCLS Fund IV Investments. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund IV Investments. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-164389 · ownership.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

BCLS Fund IV Investments GP, LLC · CIK 0002015967 · 10% owner

BCLS Fund IV Investments, L.P. · CIK 0002015454 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 22,583,268

F3 · ownership.nature: Represents securities held directly by BCLS Fund IV Investments, LP ("BCLS Fund IV Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the managing member of BCLS Fund IV Investments GP, LLC ("BCLS Fund IV Investments GP"), which is the general partner of BCLS Fund IV Investments. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund IV Investments. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-164389 · ownership.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

BCLS Fund IV Investments GP, LLC · CIK 0002015967 · 10% owner

BCLS Fund IV Investments, L.P. · CIK 0002015454 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 21,020,768

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · price: Each share of the Issuer's Series B Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund IV Investments, LP ("BCLS Fund IV Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the managing member of BCLS Fund IV Investments GP, LLC ("BCLS Fund IV Investments GP"), which is the general partner of BCLS Fund IV Investments. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund IV Investments. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-164389 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

BCLS Fund IV Investments GP, LLC · CIK 0002015967 · 10% owner

BCLS Fund IV Investments, L.P. · CIK 0002015454 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 16,875,000

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series A-1 Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 1:1 basis upon the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund IV Investments, LP ("BCLS Fund IV Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the managing member of BCLS Fund IV Investments GP, LLC ("BCLS Fund IV Investments GP"), which is the general partner of BCLS Fund IV Investments. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund IV Investments. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Fund IV Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0001193125-26-041349 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 10,448,158

F1 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-107981 · ownership.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Common Stock · 433,924 shares

Expires 2029-01-24

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F2 · derivative.exercise_date: The outstanding principal amount of the Subordinated Convertible Promissory note automatically converted into shares of the Issuer's Common Stock upon consummation of the Issuer's initial public offering at a conversion price of 80% of the price per share in the Issuer's initial public offering.

F3 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-107981 · ownership.xml · derivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Common Stock · 12,014,234 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series F Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 0.342466:1 basis immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.exercise_date: Each share of the Issuer's Series F Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 0.342466:1 basis immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.expiration_date: Each share of the Issuer's Series F Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 0.342466:1 basis immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-107981 · ownership.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 12,448,158

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F3 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-107981 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 12,014,234

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series F Preferred Stock automatically converted into shares of the Issuer's Common Stock on a 0.342466:1 basis immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F3 · ownership.nature: Represents securities held directly by BCLS Fund III Investments, LP ("BCLS Fund III Investments").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the managing member of BCLS Fund III Investments GP, LLC ("BCLS Fund III Investments GP"), which is the general partner of BCLS Fund III Investments. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Investments. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Investments GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-025011 · ownership.xml · derivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

BCLS SB Investco, LP · CIK 0001728056 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investco (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

BCLS II Equity Opportunities, LP · CIK 0001814474 · 10% owner

BCLS II Equity Opportunities GP, LLC · CIK 0002008174 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 6,444,170

Underlying: Common Stock · 6,444,170 shares

Expires not disclosed

F1 · kind: On February 19, 2025, BCLS II Investco, LP ("BCLS II Investco") purchased 1,000,000 shares of the Issuer's common stock and a pre-funded warrant to purchase 6,444,170 shares of the Issuer's common stock at a purchase price of $4.03 and $4.029, respectively, in an underwritten public offering (the "February 2025 Underwritten Offering").

F2 · derivative.exercise_date: The pre-funded warrant cannot be exercised if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated with the holder for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then outstanding immediately following such exercise.

F3 · derivative.expiration_date: The pre-funded warrant does not expire.

F2 · derivative.underlying_shares: The pre-funded warrant cannot be exercised if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated with the holder for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of shares of the Issuer's common stock then outstanding immediately following such exercise.

F5 · ownership.nature: Represents a pre-funded warrant to purchase 6,444,170 shares of the Issuer's common stock held directly by BCLS II Investco, after giving effect to the closing of the February 2025 Underwritten Offering.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose managing member is BCLS Fund II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS Fund II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS Fund II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F11 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") (i) is the general partner of BCLSP, (ii) is the manager of BCLSI II and (iii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-025011 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

BCLS SB Investco, LP · CIK 0001728056 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investco (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

BCLS II Equity Opportunities, LP · CIK 0001814474 · 10% owner

BCLS II Equity Opportunities GP, LLC · CIK 0002008174 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 5,034,582

F1 · kind: On February 19, 2025, BCLS II Investco, LP ("BCLS II Investco") purchased 1,000,000 shares of the Issuer's common stock and a pre-funded warrant to purchase 6,444,170 shares of the Issuer's common stock at a purchase price of $4.03 and $4.029, respectively, in an underwritten public offering (the "February 2025 Underwritten Offering").

F4 · ownership.nature: Represents 528,660 shares of the Issuer's common stock held directly by BCLS SB Investco, LP ("BCLS SB"), 267,257 shares of the Issuer's common stock held directly by Bain Capital Life Sciences Fund II, L.P. ("BCLS Fund II"), 3,301,955 shares of the Issuer's common stock held directly by BCLS II Investco, 904,160 shares of the Issuer's common stock held directly by BCLS II Equity Opportunities, LP ("BCLS II Equity") and 32,550 shares of the Issuer's common stock held directly by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS II Investco, BCLS SB, BCLS Fund II and BCLS II Equity, the "Bain Capital Life Sciences Entities"), after giving effect to the closing of the February 2025 Underwritten Offering.

F6 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS SB. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS SB. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F7 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS Fund II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose managing member is BCLS Fund II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS Fund II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS Fund II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F9 · ownership.nature: BCLS II Equity Opportunities GP, LLC ("BCLS II Equity GP"), whose manager is BCLS Fund II, is the general partner of BCLS II Equity. As a result, each of BCLSI II, BCLS Fund II and BCLS II Equity GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Equity. Each of BCLSI II, BCLS Fund II and BCLS II Equity GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F10 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F11 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") (i) is the general partner of BCLSP, (ii) is the manager of BCLSI II and (iii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-004870 · ownership.xml · derivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

Bain Capital Life Sciences Opportunities IV GP, LLC · CIK 0002015657 · 10% owner

Bain Capital Life Sciences Opportunities IV, L.P. · CIK 0002015553 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 3,500,000

Underlying: Common Stock · 3,500,000 shares

Expires not disclosed

F4 · kind: On January 10, 2025, BCLS Opportunities IV entered into an exchange agreement with the Issuer pursuant to which BCLS Opportunities IV exchanged 3,500,000 shares of Common Stock for a pre-funded warrant to purchase 3,500,000 shares of common stock in reliance on the exemption from registration contained in Section 3(a)(9) of the Securities Act of 1933, as amended. The exchange transaction did not result in any change in the Bain Capital Life Sciences Entities pecuniary interest in the subject equity securities.

F5 · shares: BCLS Opportunities IV is prohibited from exercising this pre-funded warrant if the Bain Capital Life Sciences Entities would, in the aggregate, beneficially own more than 9.99% of the total number of shares of common stock then issued and outstanding immediately after giving effect to such exercise.

F4 · price: On January 10, 2025, BCLS Opportunities IV entered into an exchange agreement with the Issuer pursuant to which BCLS Opportunities IV exchanged 3,500,000 shares of Common Stock for a pre-funded warrant to purchase 3,500,000 shares of common stock in reliance on the exemption from registration contained in Section 3(a)(9) of the Securities Act of 1933, as amended. The exchange transaction did not result in any change in the Bain Capital Life Sciences Entities pecuniary interest in the subject equity securities.

F6 · derivative.expiration_date: The pre-funded warrant does not expire.

F5 · derivative.underlying_shares: BCLS Opportunities IV is prohibited from exercising this pre-funded warrant if the Bain Capital Life Sciences Entities would, in the aggregate, beneficially own more than 9.99% of the total number of shares of common stock then issued and outstanding immediately after giving effect to such exercise.

F5 · balance_after: BCLS Opportunities IV is prohibited from exercising this pre-funded warrant if the Bain Capital Life Sciences Entities would, in the aggregate, beneficially own more than 9.99% of the total number of shares of common stock then issued and outstanding immediately after giving effect to such exercise.

F1 · ownership.nature: Represents securities held directly by Bain Capital Life Sciences Opportunities IV, L.P. ("BCLS Opportunities IV").

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the sole member of Bain Capital Life Sciences Opportunities IV GP, LLC ("BCLS Opportunities IV GP" and, together with BCLSI, BCLS Fund IV GP, BCLS Fund IV, BCLS Opportunities IV GP and BCLS Opportunities IV, the "Bain Capital Life Sciences Entities"), which is the general partner of BCLS Opportunities IV. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Opportunities IV. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-004870 · ownership.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

Bain Capital Life Sciences Opportunities IV GP, LLC · CIK 0002015657 · 10% owner

Bain Capital Life Sciences Opportunities IV, L.P. · CIK 0002015553 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 4,300,000

F4 · kind: On January 10, 2025, BCLS Opportunities IV entered into an exchange agreement with the Issuer pursuant to which BCLS Opportunities IV exchanged 3,500,000 shares of Common Stock for a pre-funded warrant to purchase 3,500,000 shares of common stock in reliance on the exemption from registration contained in Section 3(a)(9) of the Securities Act of 1933, as amended. The exchange transaction did not result in any change in the Bain Capital Life Sciences Entities pecuniary interest in the subject equity securities.

F4 · price: On January 10, 2025, BCLS Opportunities IV entered into an exchange agreement with the Issuer pursuant to which BCLS Opportunities IV exchanged 3,500,000 shares of Common Stock for a pre-funded warrant to purchase 3,500,000 shares of common stock in reliance on the exemption from registration contained in Section 3(a)(9) of the Securities Act of 1933, as amended. The exchange transaction did not result in any change in the Bain Capital Life Sciences Entities pecuniary interest in the subject equity securities.

F1 · ownership.nature: Represents securities held directly by Bain Capital Life Sciences Opportunities IV, L.P. ("BCLS Opportunities IV").

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the sole member of Bain Capital Life Sciences Opportunities IV GP, LLC ("BCLS Opportunities IV GP" and, together with BCLSI, BCLS Fund IV GP, BCLS Fund IV, BCLS Opportunities IV GP and BCLS Opportunities IV, the "Bain Capital Life Sciences Entities"), which is the general partner of BCLS Opportunities IV. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Opportunities IV. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-25-004870 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences IV General Partner, LLC · CIK 0001996931 · 10% owner

Bain Capital Life Sciences Fund IV, L.P. · CIK 0001996979 · 10% owner

Bain Capital Life Sciences Opportunities IV GP, LLC · CIK 0002015657 · 10% owner

Bain Capital Life Sciences Opportunities IV, L.P. · CIK 0002015553 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 7,800,000

F3 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $5.44 to $5.92, inclusive. The reporting persons undertake to provide to the Issuer, any securityholder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

F1 · ownership.nature: Represents securities held directly by Bain Capital Life Sciences Opportunities IV, L.P. ("BCLS Opportunities IV").

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences IV General Partner, LLC ("BCLS Fund IV GP"), which is the general partner of Bain Capital Life Sciences Fund IV, L.P. ("BCLS Fund IV"), which is the sole member of Bain Capital Life Sciences Opportunities IV GP, LLC ("BCLS Opportunities IV GP" and, together with BCLSI, BCLS Fund IV GP, BCLS Fund IV, BCLS Opportunities IV GP and BCLS Opportunities IV, the "Bain Capital Life Sciences Entities"), which is the general partner of BCLS Opportunities IV. As a result, each of BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Opportunities IV. BCLSI, BCLS Fund IV GP, BCLS Fund IV and BCLS Opportunities IV GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-24-137335 · ownership.xml · derivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

BCLS Fund III Investments, LP · CIK 0001952107 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

BCLS Fund III Investments GP, LLC · CIK 0001952080 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investco (GP), LLC · CIK 0001819101 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 1,632,653

Underlying: Ordinary Shares · 1,632,653 shares

Expires not disclosed

F2 · derivative.exercise_date: The pre-funded warrants cannot be exercised if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated with the holder for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of Ordinary Shares then outstanding immediately following such exercise.

F3 · derivative.expiration_date: The pre-funded warrants do not expire.

F2 · derivative.underlying_shares: The pre-funded warrants cannot be exercised if, as a result of such exercise, the holder, together with its affiliates and any other persons whose beneficial ownership would be aggregated with the holder for purposes of Section 13(d) of the Act, would beneficially own more than 9.99% of the total number of Ordinary Shares then outstanding immediately following such exercise.

F1 · ownership.nature: Represents a pre-funded warrant to purchase 1,257,141 Ordinary Shares and a pre-funded warrant to purchase 375,512 Ordinary Shares, purchased by Bain Capital Life Sciences Opportunities III, LP ("BCLS Fund III Opportunities") and BCLS II Equity Opportunities, LP ("BCLS Fund II Opportunities"), respectively, in an underwritten public offering.

F4 · ownership.nature: Bain Capital Life Sciences III General Partner, LLC ("BCLS III GP") is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS III"), which is the sole member of Bain Capital Life Sciences Opportunities III GP, LLC ("BCLS Fund III Opportunities GP"), which is the general partner of BCLS Fund III Opportunities. As a result, each of BCLS III GP and BCLS III may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Opportunities. Each of BCLS III GP and BCLS III disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F5 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of Bain Capital Life Sciences Fund II, L.P. ("BCLS Fund II"), which is the manager of BCLS II Equity Opportunities GP, LLC, which is the general partner of BCLS Fund II Opportunities. As a result, each of BCLSI II and BCLS Fund II may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund II Opportunities. Each of BCLSI II and BCLS Fund II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of each of BCLS III GP and BCLSI II. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by each of BCLS Fund III Opportunities and BCLS Fund II Opportunities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-24-015358 · ownership.xml · derivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

Bain Capital Life Sciences Opportunities III GP, LLC · CIK 0001964467 · 10% owner

Bain Capital Life Sciences Opportunities III, LP · CIK 0001950105 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Common Stock · 2,713,868 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series B Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a ratio of one-for-4.5511 immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.exercise_date: Each share of the Issuer's Series B Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a ratio of one-for-4.5511 immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F1 · derivative.expiration_date: Each share of the Issuer's Series B Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a ratio of one-for-4.5511 immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F2 · ownership.nature: Represents 12,351,087 shares of the Issuer's Series B Convertible Preferred Stock held directly by Bain Capital Life Sciences Opportunities III, LP ("BCLS Fund III Opportunities").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the sole member of Bain Capital Life Sciences Opportunities III GP, LLC ("BCLS Fund III Opportunities GP"), which is the general partner of BCLS Fund III Opportunities. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Opportunities. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-24-015358 · ownership.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

Bain Capital Life Sciences Opportunities III GP, LLC · CIK 0001964467 · 10% owner

Bain Capital Life Sciences Opportunities III, LP · CIK 0001950105 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 3,163,868

F3 · ownership.nature: Represents 450,000 shares of the Issuer's Common Stock purchased by BCLS Fund III Opportunities in the Issuer's initial public offering.

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the sole member of Bain Capital Life Sciences Opportunities III GP, LLC ("BCLS Fund III Opportunities GP"), which is the general partner of BCLS Fund III Opportunities. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Opportunities. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-24-015358 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences III General Partner, LLC · CIK 0001952106 · 10% owner

Bain Capital Life Sciences Fund III, L.P. · CIK 0001875273 · 10% owner

Bain Capital Life Sciences Opportunities III GP, LLC · CIK 0001964467 · 10% owner

Bain Capital Life Sciences Opportunities III, LP · CIK 0001950105 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 2,713,868

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series B Convertible Preferred Stock automatically converted into shares of the Issuer's Common Stock at a ratio of one-for-4.5511 immediately prior to the closing of the Issuer's initial public offering. These securities had no expiration date.

F2 · ownership.nature: Represents 12,351,087 shares of the Issuer's Series B Convertible Preferred Stock held directly by Bain Capital Life Sciences Opportunities III, LP ("BCLS Fund III Opportunities").

F4 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of Bain Capital Life Sciences III General Partner, LLC ("BCLS Fund III GP"), which is the general partner of Bain Capital Life Sciences Fund III, L.P. ("BCLS Fund III"), which is the sole member of Bain Capital Life Sciences Opportunities III GP, LLC ("BCLS Fund III Opportunities GP"), which is the general partner of BCLS Fund III Opportunities. As a result, each of BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund III Opportunities. BCLSI, BCLS Fund III GP, BCLS Fund III and BCLS Fund III Opportunities GP each disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000950170-24-004289 · ownership.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · Director · 10% owner

BCLS SB Investco, LP · CIK 0001728056 · Director · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · Director · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · Director · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · Director · 10% owner

BCLS II Investco, LP · CIK 0001818893 · Director · 10% owner

BCLS II Investco (GP), LLC · CIK 0001819101 · Director · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 4,034,582

F1 · kind: On January 8, 2024, BCLS II Equity Opportunities, LP ("BCLS II Equity") entered into a securities purchase agreement with the Issuer pursuant to which the Issuer agreed to issue and sell 904,160 shares of Common Stock to BCLS II Equity at a price of $5.53 per share (the "January 2024 Private Placement"). The January 2024 Private Placement closed on January 11, 2024. BCLS II Equity and BCLS II Equity Opportunities GP, LLC ("BCLS II Equity GP"), its general partner, plan to file a Form 3 with the Securities and Exchange Commission in connection with the acquisition of shares of Common Stock by BCLS II Equity in the January 2024 Private Placement.

F2 · ownership.nature: Represents 528,660 shares of Common Stock held directly by BCLS SB Investco, LP ("BCLS SB"), 267,257 shares of Common Stock held directly by Bain Capital Life Sciences Fund II, L.P. ("BCLS Fund II"), 2,301,955 shares of Common Stock held directly by BCLS II Investco, LP ("BCLS II Investco"), 904,160 shares of Common Stock held directly by BCLS II Equity and 32,550 shares of Common Stock held directly by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS SB, BCLS Fund II, BCLS II Investco and BCLS II Equity, the "Bain Capital Life Sciences Entities"), after giving effect to the closing of the January 2024 Private Placement.

F3 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS SB. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS SB. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F4 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS Fund II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F5 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose managing member is BCLS Fund II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS Fund II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS Fund II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: BCLS Fund II is the manager of BCLS II Equity GP. As a result, each of BCLSI II and BCLS Fund II may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Equity. Each of BCLSI II and BCLS Fund II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F7 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F8 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") (i) is the general partner of BCLSP, (ii) is the manager of BCLSI II and (iii) governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-23-014139 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 5,701,926

F1 · shares: Represents 300,000 shares of Common Stock purchased by BCLS I Investco, LP ("BCLS I Investco") on May 25, 2023.

F2 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $2.08 to $2.25, inclusive. The reporting persons undertake to provide to the Issuer, any securityholder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the range set forth herein.

F3 · ownership.nature: Represents shares of Common Stock held by Bain Capital Life Sciences Fund, L.P. ("BCLS Fund I"), BCLS I Investco and BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS Fund I and BCLS I Investco, the "Bain Capital Life Sciences Entities"). Following the completion of the transactions reported in footnote (1) above, BCLS Fund I, BCLS I Investco and BCIPLS each holds 2,940,627, 2,460,298 and 301,001 shares of Common Stock, respectively.

F4 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS Fund I. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS Fund I. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F5 · ownership.nature: BCLS I Investco GP, LLC ("BCLS I Investco GP"), whose manager is BCLS Fund I, is the general partner of BCLS I Investco. As a result, each of BCLSP, BCLS Fund I and BCLS I Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS I Investco. Each of BCLSP, BCLS Fund I and BCLS I Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F7 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the general partner of BCLSP and governs the investment strategy and decision making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-21-047829 · doc4.xml · nonDerivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investo (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 2,805,413

F1 · kind: On December 8, 2021, December 9, 2021 and December 10, 2021, BCLS II Investco, LP ("BCLS II Investco") purchased 13,458, 4,011 and 25,000 shares of the Issuer's common stock, respectively.

F5 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $10.13 to $10.25, inclusive.

F6 · ownership.nature: Represents shares of the Issuer's common stock held by Bain Capital Life Sciences Fund II, L.P. ("BCLS II"), BCLS II Investco and BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS II and BCLS II Investco, the "Bain Capital Life Sciences Entities"). Following the completion of the transactions reported in footnote (1) to this Form 4, BCLS II, BCLS II Investco and BCIPLS each holds 1,348,682, 1,292,469 and 164,262 shares of the Issuer's common stock, respectively.

F7 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose manager is BCLS II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F9 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F10 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of BCLSI II and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-21-047829 · doc4.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investo (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 2,802,225

F1 · kind: On December 8, 2021, December 9, 2021 and December 10, 2021, BCLS II Investco, LP ("BCLS II Investco") purchased 13,458, 4,011 and 25,000 shares of the Issuer's common stock, respectively.

F4 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $9.07 to $10.00, inclusive.

F6 · ownership.nature: Represents shares of the Issuer's common stock held by Bain Capital Life Sciences Fund II, L.P. ("BCLS II"), BCLS II Investco and BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS II and BCLS II Investco, the "Bain Capital Life Sciences Entities"). Following the completion of the transactions reported in footnote (1) to this Form 4, BCLS II, BCLS II Investco and BCIPLS each holds 1,348,682, 1,292,469 and 164,262 shares of the Issuer's common stock, respectively.

F7 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose manager is BCLS II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F9 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F10 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of BCLSI II and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-21-047829 · doc4.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investo (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 2,780,413

F1 · kind: On December 8, 2021, December 9, 2021 and December 10, 2021, BCLS II Investco, LP ("BCLS II Investco") purchased 13,458, 4,011 and 25,000 shares of the Issuer's common stock, respectively.

F3 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $9.53 to $10.00, inclusive.

F6 · ownership.nature: Represents shares of the Issuer's common stock held by Bain Capital Life Sciences Fund II, L.P. ("BCLS II"), BCLS II Investco and BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS II and BCLS II Investco, the "Bain Capital Life Sciences Entities"). Following the completion of the transactions reported in footnote (1) to this Form 4, BCLS II, BCLS II Investco and BCIPLS each holds 1,348,682, 1,292,469 and 164,262 shares of the Issuer's common stock, respectively.

F7 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose manager is BCLS II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F9 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F10 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of BCLSI II and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-21-047829 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund II, L.P. · CIK 0001773187 · 10% owner

Bain Capital Life Sciences Investors II, LLC · CIK 0001796155 · 10% owner

BCLS II Investco, LP · CIK 0001818893 · 10% owner

BCLS II Investo (GP), LLC · CIK 0001819101 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 2,776,402

F1 · kind: On December 8, 2021, December 9, 2021 and December 10, 2021, BCLS II Investco, LP ("BCLS II Investco") purchased 13,458, 4,011 and 25,000 shares of the Issuer's common stock, respectively.

F2 · price: The price reported in Column 4 is a weighted average price. The shares were purchased in multiple transactions at prices ranging from $9.41 to $9.75, inclusive. The reporting persons undertake to provide to the Issuer, any securityholder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in footnotes (2) through (5) to this Form 4.

F6 · ownership.nature: Represents shares of the Issuer's common stock held by Bain Capital Life Sciences Fund II, L.P. ("BCLS II"), BCLS II Investco and BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS II and BCLS II Investco, the "Bain Capital Life Sciences Entities"). Following the completion of the transactions reported in footnote (1) to this Form 4, BCLS II, BCLS II Investco and BCIPLS each holds 1,348,682, 1,292,469 and 164,262 shares of the Issuer's common stock, respectively.

F7 · ownership.nature: Bain Capital Life Sciences Investors II, LLC ("BCLSI II") is the general partner of BCLS II. As a result, BCLSI II may be deemed to share voting and dispositive power with respect to the securities held by BCLS II. BCLSI II disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F8 · ownership.nature: BCLS II Investco (GP), LLC ("BCLS II Investco GP"), whose manager is BCLS II, is the general partner of BCLS II Investco. As a result, each of BCLSI II, BCLS II and BCLS II Investco GP may be deemed to share voting and dispositive power with respect to the securities held by BCLS II Investco. Each of BCLSI II, BCLS II and BCLS II Investco GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F9 · ownership.nature: Boylston Coinvestors, LLC is the general partner of BCIPLS.

F10 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI") is the manager of BCLSI II and governs the investment strategy and decision-making process with respect to investments held by BCIPLS. As a result, BCLSI may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

SEC source: 0000899243-21-032893 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

BC SW, LP · CIK 0001786351 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 4,831,307

F1 · ownership.nature: Represents shares of common stock held directly by BC SW, LP.

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BC SW, LP. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by BC SW, LP. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F3 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-029222 · doc4.xml · derivative · entry 5

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Class A Common Stock · 1,334,562 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.exercise_date: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.expiration_date: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F3 · ownership.nature: Represents 6,053,214 shares of the Issuer's Series C1 Preferred Stock held by BCLS and 619,605 shares of the Issuer's Series C1 Preferred Stock held by BCIPLS, which were automatically converted into 1,210,642 and 123,920 shares of the Issuer's Class A Common stock, respectively, immediately prior to the closing of the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F7 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-029222 · doc4.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 0

Underlying: Class A Common Stock · 6,999,998 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.exercise_date: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.expiration_date: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F2 · ownership.nature: Represents 31,750,072 shares of the Issuer's Series B1 Preferred Stock held by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 3,249,929 shares of the Issuer's Series B1 Preferred Stock held by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities"), which were automatically converted into 6,350,013 and 649,985 shares of the Issuer's Class A Common Stock, respectively, immediately prior to the closing of the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F7 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-029222 · doc4.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 8,434,560

F4 · ownership.nature: Represents 90,714 and 9,286 shares of the Issuer's Class A Common Stock purchased by BCLS and BCIPLS, respectively, in the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F7 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-029222 · doc4.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 8,334,560

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F3 · ownership.nature: Represents 6,053,214 shares of the Issuer's Series C1 Preferred Stock held by BCLS and 619,605 shares of the Issuer's Series C1 Preferred Stock held by BCIPLS, which were automatically converted into 1,210,642 and 123,920 shares of the Issuer's Class A Common stock, respectively, immediately prior to the closing of the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F7 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-029222 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 6,999,998

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series B1 Preferred Stock and Series C1 Preferred Stock automatically converted into 0.2 of a share of the Issuer's Class A Common Stock immediately prior to the closing of the Issuer's initial public offering.

F2 · ownership.nature: Represents 31,750,072 shares of the Issuer's Series B1 Preferred Stock held by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 3,249,929 shares of the Issuer's Series B1 Preferred Stock held by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities"), which were automatically converted into 6,350,013 and 649,985 shares of the Issuer's Class A Common Stock, respectively, immediately prior to the closing of the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of its or their pecuniary interest therein.

F7 · ownership.nature: Jeffrey Schwartz is a director of the Issuer.

SEC source: 0000899243-21-011153 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

BC SW, LP · CIK 0001786351 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · Director · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 5,831,307

F1 · ownership.nature: Represents shares of common stock held directly by BC SW, LP.

F2 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BC SW, LP. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the securities held by BC SW, LP. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

F3 · ownership.nature: Mr. Schwartz is a director of the Issuer.

SEC source: 0000899243-20-029321 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Koppel Adam · CIK 0001578965 · Director · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 8,891,758

F1 · kind: On October 26, 2020, Bain Capital Life Sciences Fund, L.P. ("BCLS") and BCIP Life Sciences Fund, LP ("BCIPLS and, together with BCLS, the "Bain Capital Life Sciences Entities") purchased an aggregate of 3,333,333 shares of Common Stock in an underwritten public offering at a price per share of $3.00. BCLS purchased 3,023,816 of such shares and BCIPLS purchased 309,517 of such shares. Following such purchases, BCLS holds 8,066,113 shares of Common Stock and BCIPLS holds 825,645 shares of Common Stock.

F2 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F3 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

F4 · ownership.nature: Adam Koppel is a director of the Issuer.

SEC source: 0000899243-20-020554 · doc4.xml · derivative · entry 5

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

Underlying: Common Stock · 319,243 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.exercise_date: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.expiration_date: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F3 · ownership.nature: Represents 2,551,384 shares of Series D Stock held of record by BCLS and 261,159 shares of Series D Stock held of record by BCIPLS.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-020554 · doc4.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

Underlying: Common Stock · 2,522,385 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.exercise_date: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F1 · derivative.expiration_date: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F2 · ownership.nature: Represents 20,158,775 shares of Series C Stock held of record by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 2,063,446 shares of Series C Stock held of record by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities").

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-020554 · doc4.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 3,241,628

F4 · ownership.nature: Represents 362,858 and 37,142 shares of the Issuer's Common Stock purchased by BCLS and BCIPLS, respectively, in the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-020554 · doc4.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 2,841,628

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F3 · ownership.nature: Represents 2,551,384 shares of Series D Stock held of record by BCLS and 261,159 shares of Series D Stock held of record by BCIPLS.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-020554 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 2,522,385

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of Series C Preferred Stock ("Series C Stock") and Series D Preferred Stock ("Series D Stock") automatically converted on a 1-for-8.81 basis into the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering.

F2 · ownership.nature: Represents 20,158,775 shares of Series C Stock held of record by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 2,063,446 shares of Series C Stock held of record by BCIP Life Sciences Associates, LP ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities").

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coinvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dispositive power over the shares held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-003487 · doc4.xml · derivative · entry 5

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

Underlying: Common Stock · 859,573 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F1 · derivative.exercise_date: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F1 · derivative.expiration_date: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F3 · ownership.nature: Represents 779,758 shares of Series C Stock held of record by BCLS and 79,815 shares of Series C Stock held of record by BCIPLS.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coninvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dipositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-003487 · doc4.xml · derivative · entry 4

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

Underlying: Common Stock · 2,825,602 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F1 · derivative.exercise_date: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F1 · derivative.expiration_date: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F2 · ownership.nature: Represents 2,563,231 shares of Series B Stock held of record by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 262,371 shares of Series B Stock held of record by BCIP Life Sciences Associates, LP. ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities").

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coninvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dipositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-003487 · doc4.xml · nonDerivative · entry 3

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 3,979,292

F4 · ownership.nature: Represents 266,807 and 27,310 shares of Common Stock purchased by BCLS and BCIPLS, respectively, in the Issuer's initial public offering.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coninvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dipositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-003487 · doc4.xml · nonDerivative · entry 2

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 3,685,175

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F3 · ownership.nature: Represents 779,758 shares of Series C Stock held of record by BCLS and 79,815 shares of Series C Stock held of record by BCIPLS.

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coninvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dipositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.

SEC source: 0000899243-20-003487 · doc4.xml · nonDerivative · entry 1

Bain Capital Life Sciences Investors, LLC · CIK 0001703031 · 10% owner

Bain Capital Life Sciences Partners, LP · CIK 0001703030 · 10% owner

Bain Capital Life Sciences Fund, L.P. · CIK 0001687968 · 10% owner

BCIP Life Sciences Associates, LP · CIK 0001702921 · 10% owner

Koppel Adam · CIK 0001578965 · 10% owner

Schwartz Jeffrey Lawrence · CIK 0001702957 · 10% owner

Joint disclosure: these amounts are not allocated separately to each reporting owner.

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 2,825,602

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each share of the Issuer's Series B Preferred Stock ("Series B Stock") and Series C Preferred Stock ("Series C Stock") automatically converted into 1 share of the Issuer's Common Stock immediately prior to the closing of the Issuer's initial public offering. The Series B Stock and the Series C Stock each had no expiration date.

F2 · ownership.nature: Represents 2,563,231 shares of Series B Stock held of record by Bain Capital Life Sciences Fund, L.P. ("BCLS") and 262,371 shares of Series B Stock held of record by BCIP Life Sciences Associates, LP. ("BCIPLS" and, together with BCLS, the "Bain Capital Life Sciences Entities").

F5 · ownership.nature: Bain Capital Life Sciences Partners, LP ("BCLSP") is the general partner of BCLS. As a result, BCLSP may be deemed to share voting and dispositive power with respect to the securities held by BCLS. BCLSP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

F6 · ownership.nature: Bain Capital Life Sciences Investors, LLC ("BCLSI"), whose managers are Jeffrey Schwartz and Adam Koppel, is the general partner of BCLSP and governs the investment strategy and decision-making process with respect to investments held by BCIPLS, whose general partner is Boylston Coninvestors, LLC. As a result, each of BCLSI, Mr. Schwartz and Dr. Koppel may be deemed to share voting and dipositive power with respect to the securities held by the Bain Capital Life Sciences Entities. BCLSI, Mr. Schwartz and Dr. Koppel each disclaim beneficial ownership of such securities except to the extent of their pecuniary interest therein.