JBIO

SEC source: 0001493152-21-031751 · ownership.xml · derivative · entry 1

NIVEN RALPH · CIK 0001168060 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 65,433

Underlying: Common Stock · 65,433 shares

Expires 2031-12-13

F1 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on January 14, 2022.

SEC source: 0001493152-21-031754 · ownership.xml · derivative · entry 1

Dake Benjamin T · CIK 0001869248 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 58,000

Underlying: Common Stock · 58,000 shares

Expires 2031-12-13

F1 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on January 14, 2022.

SEC source: 0001493152-21-031753 · ownership.xml · derivative · entry 1

Gillies Hunter · CIK 0001868997 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 65,433

Underlying: Common Stock · 65,433 shares

Expires 2031-12-13

F1 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on January 14, 2022.

SEC source: 0001493152-21-031752 · ownership.xml · derivative · entry 1

Eldridge George A · CIK 0001413006 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 65,433

Underlying: Common Stock · 65,433 shares

Expires 2031-12-13

F1 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on January 14, 2022.

SEC source: 0001493152-21-031755 · ownership.xml · derivative · entry 1

NOYES TIMOTHY P · CIK 0001185035 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 204,501

Underlying: Common Stock · 204,501 shares

Expires 2031-12-13

F1 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on January 14, 2022.

SEC source: 0001104659-21-093476 · tm2122535-2_4seq1.xml · derivative · entry 1

Dorval Allison · CIK 0001625110 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2031-07-14

F1 · derivative.exercise_date: This option shall vest in 36 substantially equal monthly installments, with the first installment vesting on August 15, 2021.

SEC source: 0001104659-21-089440 · tm2121485-4_4seq1.xml · derivative · entry 3

Sofinnova Venture Partners X, L.P. · CIK 0001680200 · 10% owner

Sofinnova Management X, L.L.C. · CIK 0001680194 · 10% owner

HEALY JAMES · CIK 0001245624 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 3,401,544 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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · price: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.direct: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. Each of the Reporting Persons disclaims beneficial ownership of such securities, except to the extent of his, her or its proportionate pecuniary interest therein.

SEC source: 0001104659-21-089440 · tm2121485-4_4seq1.xml · nonDerivative · entry 2

Sofinnova Venture Partners X, L.P. · CIK 0001680200 · 10% owner

Sofinnova Management X, L.L.C. · CIK 0001680194 · 10% owner

HEALY JAMES · CIK 0001245624 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,758,686

F2 · ownership.direct: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. Each of the Reporting Persons disclaims beneficial ownership of such securities, except to the extent of his, her or its proportionate pecuniary interest therein.

SEC source: 0001104659-21-089440 · tm2121485-4_4seq1.xml · nonDerivative · entry 1

Sofinnova Venture Partners X, L.P. · CIK 0001680200 · 10% owner

Sofinnova Management X, L.L.C. · CIK 0001680194 · 10% owner

HEALY JAMES · CIK 0001245624 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,401,544

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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.direct: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. Each of the Reporting Persons disclaims beneficial ownership of such securities, except to the extent of his, her or its proportionate pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · derivative · entry 8

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 0

Underlying: Common Stock · 311,170 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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F4 · derivative.underlying_shares: These securities are held directly by a separately managed account (the "Account").

F4 · ownership.nature: These securities are held directly by a separately managed account (the "Account").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · derivative · entry 7

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 0

Underlying: Common Stock · 987,244 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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F3 · derivative.underlying_shares: These securities are held directly by RA Capital Nexus Fund, L.P. (the "Nexus Fund").

F3 · ownership.nature: These securities are held directly by RA Capital Nexus Fund, L.P. (the "Nexus Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · derivative · entry 6

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 0

Underlying: Common Stock · 2,650,562 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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F2 · derivative.underlying_shares: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · derivative · entry 5

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 0

Underlying: Common Stock · 1,287,825 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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F2 · derivative.underlying_shares: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · nonDerivative · entry 4

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 311,170

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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F4 · balance_after: These securities are held directly by a separately managed account (the "Account").

F4 · ownership.nature: These securities are held directly by a separately managed account (the "Account").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · nonDerivative · entry 3

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 987,244

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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F3 · balance_after: These securities are held directly by RA Capital Nexus Fund, L.P. (the "Nexus Fund").

F3 · ownership.nature: These securities are held directly by RA Capital Nexus Fund, L.P. (the "Nexus Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · nonDerivative · entry 2

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 6,965,568

F2 · balance_after: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089472 · tm2121512-1_4.xml · nonDerivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director · 10% owner

RA Capital Healthcare Fund LP · CIK 0001315082 · Director · 10% owner

RA Capital Nexus Fund, L.P. · CIK 0001780117 · Director

Kolchinsky Peter · CIK 0001384859 · Director · 10% owner

Shah Rajeev M. · CIK 0001619841 · 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: 4,179,854

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: On July 2, 2021, each share of Series Seed Preferred Stock and Series A Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a one-for-3.1060103 basis without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F2 · balance_after: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-21-089437 · tm2121485-3_4seq1.xml · derivative · entry 4

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · By Sofinnova Venture Parnters X, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 3,401,544 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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · price: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.nature: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. The Reporting Person disclaims beneficial ownership of such securities, except to the extent of his or her proportionate pecuniary interest therein.

SEC source: 0001104659-21-089437 · tm2121485-3_4seq1.xml · nonDerivative · entry 2

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · By Sofinnova Venture Partners X, L.P.

Disclosed balance after: 3,758,686

F2 · ownership.nature: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. The Reporting Person disclaims beneficial ownership of such securities, except to the extent of his or her proportionate pecuniary interest therein.

SEC source: 0001104659-21-089437 · tm2121485-3_4seq1.xml · nonDerivative · entry 1

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · By Sofinnova Venture Partners X, L.P.

Disclosed balance after: 3,401,544

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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.nature: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. The Reporting Person disclaims beneficial ownership of such securities, except to the extent of his or her proportionate pecuniary interest therein.

SEC source: 0001104659-21-089434 · tm2121485-1_4seq1.xml · derivative · entry 3

Atlas Venture Fund XII, L.P. · CIK 0001812049 · 10% owner

Atlas Venture Associates XII, L.P. · CIK 0001845875 · 10% owner

Atlas Venture Associates XII, LLC · CIK 0001845871 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 2,568,165 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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · price: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.direct: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP. Each of AVA XII LP and AVA XII LLC disclaim Section 16 beneficial ownership of the securities owned by Atlas Fund XII, except to the extent of its pecuniary interest therein, if any.

SEC source: 0001104659-21-089434 · tm2121485-1_4seq1.xml · nonDerivative · entry 2

Atlas Venture Fund XII, L.P. · CIK 0001812049 · 10% owner

Atlas Venture Associates XII, L.P. · CIK 0001845875 · 10% owner

Atlas Venture Associates XII, LLC · CIK 0001845871 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,103,879

F2 · ownership.direct: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP. Each of AVA XII LP and AVA XII LLC disclaim Section 16 beneficial ownership of the securities owned by Atlas Fund XII, except to the extent of its pecuniary interest therein, if any.

SEC source: 0001104659-21-089434 · tm2121485-1_4seq1.xml · nonDerivative · entry 1

Atlas Venture Fund XII, L.P. · CIK 0001812049 · 10% owner

Atlas Venture Associates XII, L.P. · CIK 0001845875 · 10% owner

Atlas Venture Associates XII, LLC · CIK 0001845871 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,568,165

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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.direct: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP. Each of AVA XII LP and AVA XII LLC disclaim Section 16 beneficial ownership of the securities owned by Atlas Fund XII, except to the extent of its pecuniary interest therein, if any.

SEC source: 0001104659-21-089435 · tm2121485-2_4seq1.xml · derivative · entry 4

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · By Atlas Venture Fund XII, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 2,568,165 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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · price: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.nature: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP.. The Reporting Person is a member of AVA XII LLC and disclaims beneficial ownership of the securities held by Atlas Fund XII, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001104659-21-089435 · tm2121485-2_4seq1.xml · nonDerivative · entry 2

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · By Atlas Venture Fund XII, L.P.

Disclosed balance after: 3,103,879

F2 · ownership.nature: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP.. The Reporting Person is a member of AVA XII LLC and disclaims beneficial ownership of the securities held by Atlas Fund XII, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001104659-21-089435 · tm2121485-2_4seq1.xml · nonDerivative · entry 1

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · By Atlas Venture Fund XII, L.P.

Disclosed balance after: 2,568,165

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 A Preferred Stock was convertible at any time at the holder's election and automatically upon the closing of the Issuer's initial public offering. The Preferred Stock converted into Common Stock on a one-for-3.1060103 basis upon the closing of the Issuer's initial public offering without payment or additional consideration. The Preferred Stock had no expiration date.

F2 · ownership.nature: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Fund XII"). The general partner of Atlas Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP.. The Reporting Person is a member of AVA XII LLC and disclaims beneficial ownership of the securities held by Atlas Fund XII, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001567619-21-013070 · doc1.xml · derivative · entry 3

Cormorant Asset Management, LP · CIK 0001583977 · Former 10% Owner

Chen Bihua · CIK 0001599214 · Former 10% Owner

Cormorant Global Healthcare Master Fund, LP · CIK 0001618442 · Former 10% Owner

Cormorant Private Healthcare Fund II, LP · CIK 0001747677 · Former 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 · 1,530,691 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: Shares of Series A Convertible Preferred Stock were convertible at any time at the holder's election, without payment of additional consideration. Such shares had no expiration date but converted into Common Stock automatically upon the closing of the Issuer's initial public offering.

F1 · price: Shares of Series A Convertible Preferred Stock were convertible at any time at the holder's election, without payment of additional consideration. Such shares had no expiration date but converted into Common Stock automatically upon the closing of the Issuer's initial public offering.

F1 · derivative.exercise_date: Shares of Series A Convertible Preferred Stock were convertible at any time at the holder's election, without payment of additional consideration. Such shares had no expiration date but converted into Common Stock automatically upon the closing of the Issuer's initial public offering.

F1 · derivative.expiration_date: Shares of Series A Convertible Preferred Stock were convertible at any time at the holder's election, without payment of additional consideration. Such shares had no expiration date but converted into Common Stock automatically upon the closing of the Issuer's initial public offering.

F2 · ownership.nature: Shares reported herein are held by Cormorant Global Healthcare Master Fund, LP (the "Master Fund") and Cormorant Private Healthcare Fund II, LP ("Fund II"). Cormorant Asset Management, LP ("Cormorant") serves as the investment manager of the Master Fund and Fund II. Bihua Chen serves as manager of the general partner of Cormorant. Each of the Reporting Persons disclaims beneficial ownership of the shares reported herein except to the extent of its or her pecuniary interest therein, and the filing of this Form 4 shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any such shares for purposes of Section 16(a) of the Securities Exchange Act of 1934 or for any other purpose.

F5 · ownership.nature: The Series A Convertible Preferred Stock represented, on an as-converted basis, (i) 318,995 shares of Common Stock held by the Master Fund and (ii) 1,211,696 shares of Common Stock held by Fund II.

SEC source: 0001567619-21-013070 · doc1.xml · nonDerivative · entry 2

Cormorant Asset Management, LP · CIK 0001583977 · Former 10% Owner

Chen Bihua · CIK 0001599214 · Former 10% Owner

Cormorant Global Healthcare Master Fund, LP · CIK 0001618442 · Former 10% Owner

Cormorant Private Healthcare Fund II, LP · CIK 0001747677 · Former 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: 2,030,691

F2 · ownership.nature: Shares reported herein are held by Cormorant Global Healthcare Master Fund, LP (the "Master Fund") and Cormorant Private Healthcare Fund II, LP ("Fund II"). Cormorant Asset Management, LP ("Cormorant") serves as the investment manager of the Master Fund and Fund II. Bihua Chen serves as manager of the general partner of Cormorant. Each of the Reporting Persons disclaims beneficial ownership of the shares reported herein except to the extent of its or her pecuniary interest therein, and the filing of this Form 4 shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any such shares for purposes of Section 16(a) of the Securities Exchange Act of 1934 or for any other purpose.

F4 · ownership.nature: Shares reported herein as purchased on July 2, 2021 represent 500,000 shares purchased by the Master Fund.

SEC source: 0001567619-21-013070 · doc1.xml · nonDerivative · entry 1

Cormorant Asset Management, LP · CIK 0001583977 · Former 10% Owner

Chen Bihua · CIK 0001599214 · Former 10% Owner

Cormorant Global Healthcare Master Fund, LP · CIK 0001618442 · Former 10% Owner

Cormorant Private Healthcare Fund II, LP · CIK 0001747677 · Former 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: 1,530,691

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: Shares of Series A Convertible Preferred Stock were convertible at any time at the holder's election, without payment of additional consideration. Such shares had no expiration date but converted into Common Stock automatically upon the closing of the Issuer's initial public offering.

F2 · ownership.nature: Shares reported herein are held by Cormorant Global Healthcare Master Fund, LP (the "Master Fund") and Cormorant Private Healthcare Fund II, LP ("Fund II"). Cormorant Asset Management, LP ("Cormorant") serves as the investment manager of the Master Fund and Fund II. Bihua Chen serves as manager of the general partner of Cormorant. Each of the Reporting Persons disclaims beneficial ownership of the shares reported herein except to the extent of its or her pecuniary interest therein, and the filing of this Form 4 shall not be construed as an admission that any of the Reporting Persons is the beneficial owner of any such shares for purposes of Section 16(a) of the Securities Exchange Act of 1934 or for any other purpose.

F3 · ownership.nature: Represents (i) 318,995 shares of Common Stock held by the Master Fund and (ii) 1,211,696 shares of Common Stock held by Fund II.

SEC source: 0001104659-21-089437 · tm2121485-3_4seq1.xml · derivative · entry 3

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,467

Underlying: Common Stock · 2,467 shares

Expires 2031-06-30

F3 · kind: This option was awarded in lieu of cash compensation pursuant to the Issuer's Non-Employee Director Compensation Policy. The shares underlying such option shall vest and become exercisable in two equal installments, with the first installment vesting on September 30, 2021 and the second installment vesting on December 31, 2021.

F3 · derivative.exercise_date: This option was awarded in lieu of cash compensation pursuant to the Issuer's Non-Employee Director Compensation Policy. The shares underlying such option shall vest and become exercisable in two equal installments, with the first installment vesting on September 30, 2021 and the second installment vesting on December 31, 2021.

SEC source: 0001104659-21-089435 · tm2121485-2_4seq1.xml · derivative · entry 3

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,153

Underlying: Common Stock · 2,153 shares

Expires 2031-06-30

F3 · kind: This option was awarded in lieu of cash compensation pursuant to the Issuer's Non-Employee Director Compensation Policy. The shares underlying such option shall vest and become exercisable in two equal installments, with the first installment vesting on September 30, 2021 and the second installment vesting on December 31, 2021.

F3 · derivative.exercise_date: This option was awarded in lieu of cash compensation pursuant to the Issuer's Non-Employee Director Compensation Policy. The shares underlying such option shall vest and become exercisable in two equal installments, with the first installment vesting on September 30, 2021 and the second installment vesting on December 31, 2021.

SEC source: 0001104659-21-088385 · tm2121189-8_4seq1.xml · derivative · entry 3

NIVEN RALPH · CIK 0001168060 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 26,300

Underlying: Common Stock · 26,300 shares

Expires 2031-06-28

F5 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting July 29, 2021.

SEC source: 0001104659-21-088374 · tm2121189-1_4seq1.xml · derivative · entry 3

Dake Benjamin T · CIK 0001869248 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 180,800

Underlying: Common Stock · 180,800 shares

Expires 2031-06-28

F5 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on July 29, 2021.

SEC source: 0001104659-21-088378 · tm2121189-3_4seq1.xml · derivative · entry 3

Gillies Hunter · CIK 0001868997 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 60,300

Underlying: Common Stock · 60,300 shares

Expires 2031-06-28

F5 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on June 29, 2022.

SEC source: 0001104659-21-088387 · tm2121189-9_4seq1.xml · derivative · entry 1

Resnick Joshua · CIK 0001690959 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2031-06-28

F1 · derivative.exercise_date: This option shall vest in 36 substantially equal monthly installments, with the first installment vesting on July 29, 2021.

F2 · ownership.direct: Under the Reporting Person's arrangement with RA Capital Management, L.P. (the "Adviser"), the Reporting Person holds the option for the benefit of the RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund, L.P. (the "Nexus Fund"). The Reporting Person is obligated to turn over to the Adviser any net cash or stock received upon exercise of the option, which will offset advisory fees owed by the Fund and Nexus Fund to the Adviser. The Reporting Person therefore disclaims beneficial ownership of the option and underlying common stock.

SEC source: 0001104659-21-088384 · tm2121189-7_4seq1.xml · derivative · entry 3

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2031-06-28

F4 · derivative.exercise_date: This option shall vest and become exercisable in 36 substantially equal monthly installments, with the first installment vesting on July 29, 2021.

SEC source: 0001104659-21-088379 · tm2121189-4_4seq1.xml · derivative · entry 3

NOYES TIMOTHY P · CIK 0001185035 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 271,200

Underlying: Common Stock · 271,200 shares

Expires 2031-06-28

F5 · derivative.exercise_date: 25% of this option shall vest and become exercisable on June 29, 2022, with the remainder vesting in 36 substantially equal monthly installments thereafter.

SEC source: 0001104659-21-088381 · tm2121189-6_4seq1.xml · derivative · entry 3

Iwicki Mark T · CIK 0001415537 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 42,200

Underlying: Common Stock · 42,200 shares

Expires 2031-06-28

F5 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on July 29, 2021.

SEC source: 0001104659-21-088380 · tm2121189-5_4seq1.xml · derivative · entry 3

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2031-06-28

F4 · derivative.exercise_date: This option shall vest in 36 substantially equal monthly installments, with the first installment vesting on July 29, 2021.

SEC source: 0001104659-21-088375 · tm2121189-2_4seq1.xml · derivative · entry 3

Eldridge George A · CIK 0001413006 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 76,900

Underlying: Common Stock · 76,900 shares

Expires 2031-06-28

F5 · derivative.exercise_date: 25% of this option shall vest and become exercisable on June 29, 2022, with the remainder vesting in 36 substantially equal monthly installments thereafter.

SEC source: 0001104659-21-088384 · tm2121189-7_4seq1.xml · derivative · entry 2

Katabi Maha · CIK 0001720685 · Director · 10% owner

10b5-1 filing: Not disclosed

Ownership: Indirect · By Sofinnova Venture Partners X, L.P.

Disclosed balance after: 10,565,238

Underlying: Common Stock · 2,602,112 shares

Expires not disclosed

F1 · derivative.exercise_price: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F3 · ownership.nature: The shares are held directly by Sofinnova Venture Partners X, L.P. ("SVP X"). Sofinnova Management X, L.L.C. ("SM X") is the general partner of SVP X and may be deemed to have sole voting, investment and dispositive power with respect to the shares held by SVP X. James I. Healy and Maha Katabi are the managing members of SM X and may be deemed to have shared voting, investment and dispositive power with respect to the shares held by SVP X. The Reporting Person disclaims beneficial ownership of such securities, except to the extent of his or her proportionate pecuniary interest therein.

SEC source: 0001104659-21-088380 · tm2121189-5_4seq1.xml · derivative · entry 2

GRAYZEL DAVID S. · CIK 0001732786 · Director

10b5-1 filing: Not disclosed

Ownership: Indirect · By Atlas Venture Fund XII, L.P.

Disclosed balance after: 7,976,754

Underlying: Common Stock · 1,964,594 shares

Expires not disclosed

F1 · derivative.exercise_price: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · derivative.exercise_date: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F1 · derivative.expiration_date: Each share of Series A Preferred Stock is convertible into shares of the Issuer's Common Stock on a one-for-3.1060103 basis. Upon the closing of the Issuer's initial public offering, all shares of Preferred Stock will automatically convert into the number of shares of Common Stock of the Issuer shown in column 7. The Preferred Stock has no expiration date.

F3 · ownership.nature: The shares are held directly by Atlas Venture Fund XII, L.P. ("Atlas Venture Fund XII"). The general partner of Atlas Venture Fund XII is Atlas Venture Associates XII, L.P. ("AVA XII LP"). Atlas Venture Associates XII, LLC ("AVA XII LLC") is the general partner of AVA XII LP. The Reporting Person is a member of AVA XII LLC and disclaims beneficial ownership of the securities held by Atlas Venture Fund XII, except to the extent of his pecuniary interest therein, if any.

SEC source: 0001104659-21-088385 · tm2121189-8_4seq1.xml · derivative · entry 2

NIVEN RALPH · CIK 0001168060 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 109,640

Underlying: Common Stock · 109,640 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F4 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on July 4, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088385 · tm2121189-8_4seq1.xml · derivative · entry 1

NIVEN RALPH · CIK 0001168060 · Chief Development Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,294

Underlying: Common Stock · 16,294 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F3 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vested on May 2, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088374 · tm2121189-1_4seq1.xml · derivative · entry 2

Dake Benjamin T · CIK 0001869248 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 328,921

Underlying: Common Stock · 328,921 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F4 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on July 4, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088374 · tm2121189-1_4seq1.xml · derivative · entry 1

Dake Benjamin T · CIK 0001869248 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 48,882

Underlying: Common Stock · 48,882 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F3 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vested on May 2, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088378 · tm2121189-3_4seq1.xml · derivative · entry 2

Gillies Hunter · CIK 0001868997 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 109,640

Underlying: Common Stock · 109,640 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F4 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vesting on July 4, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088378 · tm2121189-3_4seq1.xml · derivative · entry 1

Gillies Hunter · CIK 0001868997 · Chief Medical Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,294

Underlying: Common Stock · 16,294 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F3 · derivative.exercise_date: This option shall vest and become exercisable in 48 substantially equal monthly installments, with the first installment vested on May 2, 2021.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088379 · tm2121189-4_4seq1.xml · derivative · entry 2

NOYES TIMOTHY P · CIK 0001185035 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 493,381

Underlying: Common Stock · 493,381 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F4 · derivative.exercise_date: 25% of this option shall vest and become exercisable on June 4, 2022, with the remainder vesting in 36 substantially equal monthly installments thereafter.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

SEC source: 0001104659-21-088379 · tm2121189-4_4seq1.xml · derivative · entry 1

NOYES TIMOTHY P · CIK 0001185035 · Director · Chief Executive Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 254,253

Underlying: Common Stock · 254,253 shares

Expires 2031-04-01

F1 · derivative.exercise_price: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F2 · kind: This transaction occurred prior to the Issuer's initial public offering, and is being reported on Form 4 solely for purposes of compliance with Rule 16a-2(a) under the Securities Exchange Act of 1934, as amended. The securities covered by such transaction were previously included on the Reporting Person's Form 3.

F1 · shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F3 · derivative.exercise_date: 25% of this option shall vest and become exercisable on February 15, 2022, with the remainder vesting in 36 substantially equal monthly installments thereafter.

F1 · derivative.underlying_shares: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.

F1 · balance_after: On June 22, 2021, the Issuer completed a one-for-3.1060103 reverse stock split of the Issuer's Common Stock (the "Reverse Split"). This amount has been adjusted to give effect to the Reverse Split.