ALEC

SEC source: 0000950170-24-072515 · ownership.xml · nonDerivative · entry 1

SCHELLER RICHARD H · CIK 0001214133 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 79,250

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest on the earlier of (i) June 12, 2025 or (ii) the date of the Issuer's next annual meeting of stockholders.

SEC source: 0000950170-24-072514 · ownership.xml · nonDerivative · entry 1

Wehner David M. · CIK 0001534965 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 115,330

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest on the earlier of (i) June 12, 2025 or (ii) the date of the Issuer's next annual meeting of stockholders.

SEC source: 0000950170-24-072517 · ownership.xml · nonDerivative · entry 1

Yaffe Kristine · CIK 0001783895 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 72,709

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest on the earlier of (i) June 12, 2025 or (ii) the date of the Issuer's next annual meeting of stockholders.

F2 · balance_after: Includes 2,000 shares of common stock beneficially owned by the reporting person which were inadvertently excluded from the amount reported in Column 5 of the Form 4 filed on June 15, 2023.

SEC source: 0000950170-24-072516 · ownership.xml · nonDerivative · entry 1

GAROFALO ELIZABETH A. · CIK 0001826361 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 61,250

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest on the earlier of (i) June 12, 2025 or (ii) the date of the Issuer's next annual meeting of stockholders.

SEC source: 0000950170-24-068938 · ownership.xml · nonDerivative · entry 1

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 305,641

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $4.7987 to $4.7988. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-068939 · ownership.xml · nonDerivative · entry 1

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 188,273

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $4.7984 to $4.7987. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-068941 · ownership.xml · nonDerivative · entry 1

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,975,245

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-24-068937 · ownership.xml · nonDerivative · entry 1

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 138,037

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $4.7986 to $4.7988. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-067444 · ownership.xml · nonDerivative · entry 3

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F8 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by PVM to its members.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-067444 · ownership.xml · nonDerivative · entry 2

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 98,533

F5 · kind: Represents a change in the form of ownership of PVM by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by the Polaris Funds.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-067444 · ownership.xml · nonDerivative · entry 1

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 9,853,817

F1 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: 27,606 shares were distributed by PVPFF VI, 379,180 shares were distributed by PVP VI AIV and 93,214 shares were distributed by PVP VI AIV-B. The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and Terrance McGuire are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F3 · shares: (Continued from footnote 2) Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F4 · ownership.nature: 544,039 shares are held by PVPFF VI, 7,072,644 shares are held by PVP VI AIV, 1,738,666 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-052329 · ownership.xml · nonDerivative · entry 3

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F8 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by PVM to its members.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-052329 · ownership.xml · nonDerivative · entry 2

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 98,533

F5 · kind: Represents a change in the form of ownership of PVM by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by the Polaris Funds.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-052329 · ownership.xml · nonDerivative · entry 1

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 10,353,817

F1 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: 27,606 shares were distributed by PVPFF VI, 379,180 shares were distributed by PVP VI AIV and 93,214 shares were distributed by PVP VI AIV-B. The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and Terrance McGuire are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F3 · shares: (Continued from footnote 2) Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F4 · ownership.nature: 571,645 shares are held by PVPFF VI, 7,451,824 shares are held by PVP VI AIV, 1,831,880 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-034849 · ownership.xml · derivative · entry 2

Altmeyer Mark · CIK 0001643074 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,420

Underlying: Common Stock · 19,420 shares

Expires 2034-03-19

F2 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on April 19, 2024.

SEC source: 0000950170-24-034849 · ownership.xml · nonDerivative · entry 1

Altmeyer Mark · CIK 0001643074 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,250

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on September 1, 2024.

SEC source: 0000950170-24-034848 · ownership.xml · derivative · entry 2

DESOUZA ERROL B · CIK 0001213895 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,420

Underlying: Common Stock · 19,420 shares

Expires 2034-03-19

F2 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on April 19, 2024.

SEC source: 0000950170-24-034848 · ownership.xml · nonDerivative · entry 1

DESOUZA ERROL B · CIK 0001213895 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,250

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on September 1, 2024.

SEC source: 0000950170-24-026428 · ownership.xml · nonDerivative · entry 1

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 318,847

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $6.9217 to $6.9218. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-026429 · ownership.xml · nonDerivative · entry 1

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 196,313

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $6.9238 to $6.9247. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-026424 · ownership.xml · nonDerivative · entry 1

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,000,380

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $6.9217 to $6.9219. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-24-026427 · ownership.xml · nonDerivative · entry 1

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 144,957

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported is a weighted average price. The shares were sold in multiple transactions at prices ranging from $6.9207 to $6.9213. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-23-068620 · ownership.xml · nonDerivative · entry 1

GAROFALO ELIZABETH A. · CIK 0001826361 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,250

SEC source: 0000950170-23-068616 · ownership.xml · nonDerivative · entry 1

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 329,016

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-23-068618 · ownership.xml · nonDerivative · entry 1

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 202,314

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-23-068619 · ownership.xml · nonDerivative · entry 1

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,019,217

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-23-068617 · ownership.xml · nonDerivative · entry 1

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 150,673

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-23-051703 · ownership.xml · derivative · entry 2

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 54,500

Underlying: Common Stock · 54,500 shares

Expires 2033-10-01

F2 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on November 1, 2023.

SEC source: 0000950170-23-051703 · ownership.xml · nonDerivative · entry 1

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 341,535

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on December 1, 2023.

SEC source: 0000950170-23-051706 · ownership.xml · derivative · entry 2

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 36,000

Underlying: Common Stock · 36,000 shares

Expires 2033-10-01

F2 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on November 1, 2023.

SEC source: 0000950170-23-051706 · ownership.xml · nonDerivative · entry 1

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 207,349

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on December 1, 2023.

SEC source: 0000950170-23-051702 · ownership.xml · derivative · entry 6

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 132,500

Underlying: Common Stock · 132,500 shares

Expires 2033-10-01

F6 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on November 1, 2023.

SEC source: 0000950170-23-051702 · ownership.xml · nonDerivative · entry 1

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 2,043,048

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on December 1, 2023.

SEC source: 0000950170-23-051705 · ownership.xml · derivative · entry 2

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,000

Underlying: Common Stock · 41,000 shares

Expires 2033-10-01

F2 · derivative.exercise_date: Shares subject to the option vest in 48 equal monthly installments beginning on November 1, 2023.

SEC source: 0000950170-23-051705 · ownership.xml · nonDerivative · entry 1

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 155,247

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest in 12 equal quarterly installments beginning on December 1, 2023.

SEC source: 0000899243-23-018836 · doc4.xml · nonDerivative · entry 1

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 10,853,817

F1 · shares: 27,606 shares were sold by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), 379,180 shares were sold by Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and 93,214 shares were sold by Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: (Continued from footnote 1) The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and the Reporting Person, a member of the Issuer's board of directors, are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F3 · ownership.nature: 599,251 shares are held by PVPFF VI, 7,831,004 shares are held by PVP VI AIV, 1,925,094 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018840 · doc4.xml · nonDerivative · entry 1

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 10,853,817

F1 · shares: 27,606 shares were sold by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), 379,180 shares were sold by Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and 93,214 shares were sold by Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: (Continued from footnote 1) The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and Terrance McGuire, a member of the Issuer's board of directors, are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F3 · ownership.nature: 599,251 shares are held by PVPFF VI, 7,831,004 shares are held by PVP VI AIV, 1,925,094 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-23-046835 · ownership.xml · nonDerivative · entry 1

Kenkare-Mitra Sara · CIK 0001895592 · President and Head of R&D

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 177,935

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000950170-23-046833 · ownership.xml · nonDerivative · entry 1

Romano Gary · CIK 0001799779 · Chief Medical Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 99,349

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

F2 · price: The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $5.1939 to $5.1943. Full information regarding the number of shares sold at each separate price can be furnished to the SEC staff upon request.

SEC source: 0000950170-23-046836 · ownership.xml · nonDerivative · entry 1

Rosenthal Arnon · CIK 0001757770 · Director · Chief Executive Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,645,448

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of RSUs.

SEC source: 0000950170-23-046831 · ownership.xml · nonDerivative · entry 1

GRASSO MARC · CIK 0001748894 · Chief Financial Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,247

F1 · kind: The reported shares were sold to satisfy the reporting person's tax obligations in connection with the vesting of restricted stock units, or RSUs.

SEC source: 0000899243-23-018381 · doc4.xml · nonDerivative · entry 5

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 39,399

F11 · kind: Represents a change in the form of ownership of McGuire Family 2008 GST Non-Exempt Irrevocable Trust ("McGuire Family Trust") by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by PVM.

F12 · ownership.nature: Shares held by McGuire Family Trust. The Reporting Person, a member of the Issuer's board of directors, is the donor of McGuire Family Trust and may be deemed to have shared power to vote and dispose of the shares held by McGuire Family Trust.

SEC source: 0000899243-23-018381 · doc4.xml · nonDerivative · entry 4

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

F10 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by PVM to its members.

F8 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including the Reporting Person who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F9 · shares: (Continued from footnote 8) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F8 · ownership.nature: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including the Reporting Person who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F9 · ownership.nature: (Continued from footnote 8) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018381 · doc4.xml · nonDerivative · entry 3

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 98,553

F7 · kind: Represents a change in the form of ownership of PVM by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by the Polaris Funds.

F8 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including the Reporting Person who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F9 · shares: (Continued from footnote 8) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F8 · ownership.nature: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including the Reporting Person who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F9 · ownership.nature: (Continued from footnote 8) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018381 · doc4.xml · nonDerivative · entry 2

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 54,996

F5 · kind: Represents a change in the form of ownership of the Reporting Person by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by PVPFF VI.

F6 · balance_after: 26,250 of such shares are represented by restricted stock units, or RSUs, which vest on the earlier of (i) June 14, 2024 or (ii) the date of the Issuer's next annual meeting of stockholders.

SEC source: 0000899243-23-018381 · doc4.xml · nonDerivative · entry 1

MCGUIRE TERRANCE · CIK 0001117003 · Director · 10% owner

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 11,353,817

F1 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: 27,606 shares were distributed by PVPFF VI, 379,180 shares were distributed by PVP VI AIV and 93,214 shares were distributed by PVP VI AIV-B. The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and the Reporting Person, a member of the Issuer's board of directors, are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F3 · shares: (Continued from footnote 2) Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F4 · ownership.nature: 626,857 shares are held by PVPFF VI, 8,210,184 shares are held by PVP VI AIV, 2,018,308 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018377 · doc4.xml · nonDerivative · entry 3

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F8 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by PVM to its members.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including Terrance McGuire who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018377 · doc4.xml · nonDerivative · entry 2

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 98,533

F5 · kind: Represents a change in the form of ownership of PVM by virtue of the receipt of shares in the pro-rata in-kind distribution of common stock of the Issuer for no consideration by the Polaris Funds.

F6 · shares: Shares held by PVM. 276 shares received from PVPFF VI, 78,869 shares received from PVP VI AIV and 19,388 shares received from PVP VI AIV-B. The Managing Members, including Terrance McGuire who is a member of the Issuer's board of directors, are managing members of PVM and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F7 · shares: (Continued from footnote 6) Each of the Managing Members disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000899243-23-018377 · doc4.xml · nonDerivative · entry 1

Polaris Venture Management Co. VI, L.L.C. · CIK 0001665594 · 10% owner

Polaris Venture Partners VI (AIV), L.P. · CIK 0001767127 · 10% owner

Polaris Venture Partners Founders' Fund VI, L.P. · CIK 0001575691 · 10% owner

Polaris Venture Partners VI, L.P. · CIK 0001493463 · 10% owner

Polaris Venture Partners VI (AIV-B), L.P. · CIK 0001767130 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 11,353,817

F1 · kind: Represents a pro-rata distribution, and not a purchase or sale, without additional consideration by Polaris Venture Partners Founders' Fund VI, L.P. ("PVPFF VI"), Polaris Venture Partners VI (AIV), L.P. ("PVP VI AIV") and Polaris Venture Partners VI (AIV-B), L.P. (p/k/a PVP VI (AIV) Feeder Corp. Holding Partnership, L.P., "PVP VI AIV-B" and, together with PVPFF VI, PVP VI AIV and Polaris Venture Partners VI, L.P. ("PVP VI"), the "Polaris Funds").

F2 · shares: 27,606 shares were distributed by PVPFF VI, 379,180 shares were distributed by PVP VI AIV and 93,214 shares were distributed by PVP VI AIV-B. The general partner of each of the Polaris Funds is Polaris Venture Management Co. VI, L.L.C. ("PVM"). Each of Amir Nashat, Brian Chee, David Barrett, Bryce Youngren, Jonathan Flint, and Terrance McGuire, a member of the Issuer's board of directors, are managing members of PVM (collectively, the "Managing Members") and may be deemed to have shared power to vote and dispose of the shares held by the Polaris Funds.

F3 · shares: (Continued from footnote 2) Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

F4 · ownership.nature: 626,857 shares are held by PVPFF VI, 8,210,184 shares are held by PVP VI AIV, 2,018,308 shares are held by PVP VI AIV-B and 498,468 shares are held by PVP VI. Each of the Managing Members and PVM disclaims beneficial ownership of the securities held by the Polaris Funds, and this report shall not be deemed an admission that any of them is the beneficial owner of such securities for purposes of Section 16 or for any other purpose, except to the extent of their respective pecuniary interest therein.

SEC source: 0000950170-24-015412 · ownership.xml · nonDerivative · entry 1

SCHELLER RICHARD H · CIK 0001214133 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 44,250

F1 · shares: The reported shares are represented by restricted stock units, or RSUs, which vest as to 50% of the shares on September 1, 2023, as to 25% of the shares on December 1, 2023, and as to the remaining shares on March 1, 2024, provided the Reporting Person continues to serve as a consultant under the terms of the consulting agreement between the Reporting Person and the Issuer.