RA Capital Nexus Fund II, L.P.

SEC source: 0001415889-24-009077 · form4-03262024_120321.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 164,729

F1 · price: Received in exchange for equity of LENZ Therapeutics Operations, Inc. ("LENZ OpCo") pursuant to an Agreement and Plan of Merger and Reorganization by and among LENZ OpCo, the Issuer and Generate Merger Sub, Inc., a wholly-owned subsidiary of the Issuer ("Generate Merger Sub"), as amended (the "Merger Agreement"). Under the terms of the Merger Agreement, on March 21, 2024, Generate Merger Sub merged with and into LENZ OpCo (the "Merger"), with LENZ OpCo surviving the Merger as a wholly-owned subsidiary of the Issuer.

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund, RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"), and a separately managed account (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.

F5 · ownership.nature: These securities are held directly by the Account.

SEC source: 0001415889-24-009077 · form4-03262024_120321.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 694,755

F1 · price: Received in exchange for equity of LENZ Therapeutics Operations, Inc. ("LENZ OpCo") pursuant to an Agreement and Plan of Merger and Reorganization by and among LENZ OpCo, the Issuer and Generate Merger Sub, Inc., a wholly-owned subsidiary of the Issuer ("Generate Merger Sub"), as amended (the "Merger Agreement"). Under the terms of the Merger Agreement, on March 21, 2024, Generate Merger Sub merged with and into LENZ OpCo (the "Merger"), with LENZ OpCo surviving the Merger as a wholly-owned subsidiary of the Issuer.

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund, RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"), and a separately managed account (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.

F4 · ownership.nature: These securities are held directly by Nexus Fund II.

SEC source: 0001415889-24-009077 · form4-03262024_120321.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 2,386,301

F1 · price: Received in exchange for equity of LENZ Therapeutics Operations, Inc. ("LENZ OpCo") pursuant to an Agreement and Plan of Merger and Reorganization by and among LENZ OpCo, the Issuer and Generate Merger Sub, Inc., a wholly-owned subsidiary of the Issuer ("Generate Merger Sub"), as amended (the "Merger Agreement"). Under the terms of the Merger Agreement, on March 21, 2024, Generate Merger Sub merged with and into LENZ OpCo (the "Merger"), with LENZ OpCo surviving the Merger as a wholly-owned subsidiary of the Issuer.

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

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund, RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"), and a separately managed account (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: 0001415889-24-007006 · form4-03062024_040318.xml · derivative · 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 II, L.P. · CIK 0001825376 · 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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 1,397,849

Underlying: Common Stock · 1,397,849 shares

Expires not disclosed

F1 · derivative.exercise_date: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.99% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

F1 · derivative.expiration_date: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.99% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

F1 · ownership.nature: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.99% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

F2 · ownership.nature: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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: 0001415889-24-004509 · form4-02212024_010219.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 17,000 shares

Expires not disclosed

F6 · price: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F6 · derivative.exercise_date: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F6 · derivative.expiration_date: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky held these options and shares for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash received upon the disposition of the options and shares, which will offset advisory fees owed by the Fund and the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of these options and shares except to the extent of their pecuniary interest.

SEC source: 0001415889-24-004509 · form4-02212024_010219.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

Underlying: Common Stock · 22,278 shares

Expires not disclosed

F6 · price: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F6 · derivative.exercise_date: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F6 · derivative.expiration_date: Pursuant to the terms of the Merger Agreement, immediately prior to the Effective Time, this stock option was cancelled and converted into the right to receive, subject to the terms of the Merger Agreement, (a) an amount in cash equal to the product obtained by multiplying (1) the aggregate number of shares underlying such stock option immediately prior to the Effective Time by (2) an amount equal to (A) $15.00 less (B) the exercise price of such stock option, plus (b) one CVR for each share underlying such stock option immediately prior to the Effective Time.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky held these options and shares for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash received upon the disposition of the options and shares, which will offset advisory fees owed by the Fund and the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of these options and shares except to the extent of their pecuniary interest.

SEC source: 0001415889-24-004509 · form4-02212024_010219.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

F1 · price: In connection with the terms of an Agreement and Plan of Merger, dated as of December 11, 2023 (the "Merger Agreement"), by and among the Issuer, AstraZeneca Finance and Holdings Inc. ("Parent"), and Isochrone Merger Sub Inc., a wholly owned subsidiary of Parent ("Purchaser"), Purchaser completed a tender offer for shares of the Issuer's Common Stock at a purchase price per share of (i) $15.00 plus (ii) one non-tradable contingent value right ("CVR") per share representing the right to receive a contingent payment of up to $5.00 in cash upon achievement of specified milestones (collectively, the "Offer Price"). After completion of the tender offer, Purchaser merged with and into the Issuer (the "Merger"), effective as of February 19, 2024 (the "Effective Time"), with the Issuer continuing as the surviving entity and a wholly owned subsidiary of Parent.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F5 · ownership.nature: Held by the Nexus Fund II.

SEC source: 0001415889-24-004509 · form4-02212024_010219.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

F1 · price: In connection with the terms of an Agreement and Plan of Merger, dated as of December 11, 2023 (the "Merger Agreement"), by and among the Issuer, AstraZeneca Finance and Holdings Inc. ("Parent"), and Isochrone Merger Sub Inc., a wholly owned subsidiary of Parent ("Purchaser"), Purchaser completed a tender offer for shares of the Issuer's Common Stock at a purchase price per share of (i) $15.00 plus (ii) one non-tradable contingent value right ("CVR") per share representing the right to receive a contingent payment of up to $5.00 in cash upon achievement of specified milestones (collectively, the "Offer Price"). After completion of the tender offer, Purchaser merged with and into the Issuer (the "Merger"), effective as of February 19, 2024 (the "Effective Time"), with the Issuer continuing as the surviving entity and a wholly owned subsidiary of Parent.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F4 · ownership.nature: Held by the Fund.

SEC source: 0001415889-24-004509 · form4-02212024_010219.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnote

Disclosed balance after: 0

F1 · price: In connection with the terms of an Agreement and Plan of Merger, dated as of December 11, 2023 (the "Merger Agreement"), by and among the Issuer, AstraZeneca Finance and Holdings Inc. ("Parent"), and Isochrone Merger Sub Inc., a wholly owned subsidiary of Parent ("Purchaser"), Purchaser completed a tender offer for shares of the Issuer's Common Stock at a purchase price per share of (i) $15.00 plus (ii) one non-tradable contingent value right ("CVR") per share representing the right to receive a contingent payment of up to $5.00 in cash upon achievement of specified milestones (collectively, the "Offer Price"). After completion of the tender offer, Purchaser merged with and into the Issuer (the "Merger"), effective as of February 19, 2024 (the "Effective Time"), with the Issuer continuing as the surviving entity and a wholly owned subsidiary of Parent.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky held these options and shares for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash received upon the disposition of the options and shares, which will offset advisory fees owed by the Fund and the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of these options and shares except to the extent of their pecuniary interest.

SEC source: 0001209191-24-003175 · doc4.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 9,179,273

F1 · ownership.nature: These securities are held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund, RA Capital Nexus Fund II, L.P. (the "Nexus Fund"), and a separately managed account (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: 0001104659-23-103529 · tm2326846-1_4seq1.xml · nonDerivative · entry 2

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 8,556,774

F3 · price: This transaction was executed in multiple trades at prices ranging from $3.75 to $3.90; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F4 · balance_after: Held directly by the Fund.

F4 · ownership.nature: Held directly by the Fund.

F6 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-103529 · tm2326846-1_4seq1.xml · nonDerivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 8,365,465

F1 · price: This transaction was executed in multiple trades at prices ranging from $2.75 to $3.74; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F2 · balance_after: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F6 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-097327 · tm2325196-1_4seq1.xml · nonDerivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 5,856,774

F1 · shares: On August 29, 2023, the Fund (as defined in footnote (2)) entered into a contract to purchase the shares from a third-party seller in a privately negotiated transaction.

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

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

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-094274 · tm2324309-1_4seq1.xml · nonDerivative · entry 1

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 5,135,683

F1 · price: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on August 16, 2023.

F1 · ownership.nature: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on August 16, 2023.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Held directly by the Fund.

SEC source: 0001104659-23-089351 · tm2323320-1_4seq1.xml · derivative · entry 3

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Former 10% owners and Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Former 10% owners and Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Former 10% owners and Director

Kolchinsky Peter · CIK 0001384859 · Former 10% owners and Director

Shah Rajeev M. · CIK 0001619841 · Former 10% owners and Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

Underlying: Common Stock · 21,250 shares

Expires 2032-06-06

F1 · kind: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · kind: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F7 · price: Pursuant to the Merger Agreement, each Option to purchase shares of Common Stock that was outstanding but not vested as of immediately prior to the Closing (the "Unvested Option"), became fully vested and exercisable (the "Vested Option"). Each Vested Option was automatically cancelled and converted into the right to receive an amount in cash, without interest, less any applicable tax withholding, equal to the product obtained by multiplying (i) the excess, if any, of the Offer price over the exercise price per share of Common Stock underlying such Option by (ii) the number of shares of Common Stock underlying such Option. Except if the exercise price per share of Common Stock of the Option was equal to or greater than the Offer price, such Option was cancelled without any cash payment or other consideration being made in respect thereof.

F6 · derivative.exercise_date: The Issuer's Stock Option (the "Option") is fully vested and exercisable.

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F8 · ownership.nature: Under Dr. Jake Simson's agreement with the Adviser, Dr. Simson holds the options for the benefit of the Fund and the Nexus Fund II. Dr. Simson is obligated to turn over to the Adviser any net cash or stock received upon sale of the common stock underlying the option and restricted stock units, which will offset advisory fees owed by the Fund to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and respective underlying common stock except to the extent of their pecuniary interest.

SEC source: 0001104659-23-089351 · tm2323320-1_4seq1.xml · nonDerivative · entry 2

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Former 10% owners and Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Former 10% owners and Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Former 10% owners and Director

Kolchinsky Peter · CIK 0001384859 · Former 10% owners and Director

Shah Rajeev M. · CIK 0001619841 · Former 10% owners and Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

F1 · kind: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · kind: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F1 · price: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · price: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F1 · ownership.nature: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · ownership.nature: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F5 · ownership.nature: Held directly by the Nexus Fund II.

SEC source: 0001104659-23-089351 · tm2323320-1_4seq1.xml · nonDerivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Former 10% owners and Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Former 10% owners and Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Former 10% owners and Director

Kolchinsky Peter · CIK 0001384859 · Former 10% owners and Director

Shah Rajeev M. · CIK 0001619841 · Former 10% owners and Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 0

F1 · kind: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · kind: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F1 · price: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · price: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F1 · ownership.nature: On June 18, 2023, the Issuer entered into the Agreement and Plan of Merger (the "Merger Agreement"), with Eli Lilly and Company, an Indiana corporation (the "Parent"), and Durning Acquisition Corporation, a Delaware corporation and a direct or indirect wholly owned subsidiary of the Parent (the "Merger Sub"). Pursuant to the Merger Agreement, the Merger Sub merged with and into the Issuer (such merger and the other transactions contemplated by the Merger Agreement, the "Merger") with the Issuer surviving the Merger as a wholly owned subsidiary of the Parent.

F2 · ownership.nature: Upon the closing (the "Closing") of the Merger on August 9, 2023, each share of the Issuer's Common Stock, par value $0.0001 per share ("Common Stock"), was either (i) purchased for $48.00 per share (the "Offer Price"), without interest, less any applicable withholding taxes or (ii) automatically converted into the right to receive an amount in cash without interest, equal to the Offer Price, less any applicable withholding taxes. Immediately prior to the Closing, any repurchase rights of the Issuer or other similar restrictions on the Common Stock fully lapsed and all Common Stock became fully vested.

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F4 · ownership.nature: Held directly by the Fund.

SEC source: 0001104659-23-083857 · tm2322012-1_4seq1.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 II, L.P. · CIK 0001825376 · 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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 13,043,179

F1 · price: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on July 20, 2023.

F2 · balance_after: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F1 · ownership.nature: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on July 20, 2023.

F2 · ownership.nature: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"), RA Capital Nexus Fund II, L.P. (the "Nexus Fund II") and a separately managed account (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: 0001104659-23-083069 · tm2321745-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · 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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 503,226

Underlying: Common Stock · 503,226 shares

Expires not disclosed

F5 · derivative.exercise_date: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.9% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

F5 · derivative.expiration_date: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.9% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

F2 · ownership.nature: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F5 · ownership.nature: The Pre-Funded Warrants have no expiration date and are exercisable immediately and will be exercisable until exercise. The Pre-Funded Warrants may not be exercised to the extent such exercise would cause the holder (together with its affiliates, any other persons acting as a group together with the holder or any of the holder's affiliates, and any other persons whose beneficial ownership of the issuer's Common Stock would or could be aggregated with the holder's for purposes of Section 13(d) or Section 16 of the Securities Exchange Act of 1934, as amended) to beneficially own more than 19.9% of the Issuer's Common Stock outstanding immediately after giving effect to such exercise.

SEC source: 0001104659-23-083069 · tm2321745-1_4seq1.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 II, L.P. · CIK 0001825376 · 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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 8,117,246

F1 · price: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on July 18, 2023.

F2 · balance_after: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F1 · ownership.nature: Acquired from the Issuer pursuant to the public offering described in the Issuer's Prospectus filed with the Securities and Exchange Commission on July 18, 2023.

F2 · ownership.nature: Held directly by RA Capital Healthcare Fund, L.P. (the "Fund").

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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: 0001104659-23-075962 · tm2320008-1_4seq1.xml · derivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 40,000

Underlying: Common Stock · 40,000 shares

Expires 2033-06-26

F1 · derivative.exercise_date: The shares subject to the option will vest in full on the earlier of June 27, 2024 or the date of the Issuer's 2024 annual meeting of stockholders, which date has not been set by the Issuer's Board of Directors.

F1 · ownership.nature: The shares subject to the option will vest in full on the earlier of June 27, 2024 or the date of the Issuer's 2024 annual meeting of stockholders, which date has not been set by the Issuer's Board of Directors.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky holds the option for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky 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 the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock except to the extent of their pecuniary interest.

SEC source: 0001104659-23-072338 · tm2318968-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · 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: No plan indicated

Ownership: Indirect · See footnotes

Disclosed balance after: 12,500

Underlying: Common Stock · 12,500 shares

Expires 2033-06-13

F1 · derivative.exercise_date: The shares subject to the option will vest in equal monthly installments over the 12 months following June 14, 2023, provided that the shares subject to the option will in any case be fully vested on the date of the next annual meeting of the Company's stockholders.

F1 · ownership.nature: The shares subject to the option will vest in equal monthly installments over the 12 months following June 14, 2023, provided that the shares subject to the option will in any case be fully vested on the date of the next annual meeting of the Company's stockholders.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Mr. Simson's arrangement with the Adviser, Mr. Simson holds the option for the benefit of the Fund and the Nexus Fund II. Mr. Simson 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 the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock except to the extent of their pecuniary interest.

SEC source: 0001104659-23-070813 · tm2318619-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2033-06-05

F1 · derivative.exercise_date: The shares subject to the option will vest on the earlier of June 6, 2024 or the 2024 annual stockholder meeting, subject to Ms. Stoppel's continuous service through each such vesting date.

F1 · ownership.nature: The shares subject to the option will vest on the earlier of June 6, 2024 or the 2024 annual stockholder meeting, subject to Ms. Stoppel's continuous service through each such vesting date.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"), RA Capital Nexus Fund II, L.P. (the "Nexus Fund II") and a separately managed account (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.

F3 · ownership.nature: Under Ms. Stoppel's arrangement with the Adviser, Ms. Stoppel holds the option for the benefit of the Fund, the Nexus Fund II and the Account. Ms. Stoppel 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, the Nexus Fund II, and the Account to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.

SEC source: 0001104659-23-063233 · tm2316475-1_4seq1.xml · derivative · 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 · 10% owner

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnote

Disclosed balance after: 10,000

Underlying: Common Stock · 10,000 shares

Expires 2033-05-17

F1 · derivative.exercise_date: The shares subject to the option will vest on the earlier of May 18, 2024 or the day immediately prior to the next annual meeting of stockholders, subject to Dr. Andrew Levin's, a Partner and Managing Director of the Adviser who serves on the Issuer's board of directors, continuous service through such date.

F1 · ownership.nature: The shares subject to the option will vest on the earlier of May 18, 2024 or the day immediately prior to the next annual meeting of stockholders, subject to Dr. Andrew Levin's, a Partner and Managing Director of the Adviser who serves on the Issuer's board of directors, continuous service through such date.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"), RA Capital Nexus Fund, L.P. (the "Nexus Fund"), RA Capital Nexus Fund II, L.P. (the "Nexus Fund II") and a separately managed account (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.

F3 · ownership.nature: Under Dr. Levin's arrangement with the Adviser, Dr. Levin holds the option for the benefit of the Fund, the Nexus Fund, the Nexus Fund II and the Account. Dr. Levin 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, the Nexus Fund, the Nexus Fund II, and the Account to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.

SEC source: 0001104659-23-039250 · tm2311057-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 7,070,205

F5 · price: This transaction was executed in multiple trades at prices ranging from $27.74 to $29.50; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F6 · balance_after: Held directly by the Fund.

F6 · ownership.nature: Held directly by the Fund.

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-039250 · tm2311057-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 6,874,208

F3 · price: This transaction was executed in multiple trades at prices ranging from $29.13 to $29.50; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F4 · balance_after: Held directly by the Fund.

F4 · ownership.nature: Held directly by the Fund.

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-039250 · tm2311057-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 6,807,839

F1 · price: This transaction was executed in multiple trades at prices ranging from $28.94 to $29.50; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F2 · balance_after: Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund").

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-037172 · tm2310680-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 6,561,060

F5 · price: This transaction was executed in multiple trades at prices ranging from $26.93 to $27.76; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F6 · balance_after: Held directly by the Fund.

F6 · ownership.nature: Held directly by the Fund.

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-037172 · tm2310680-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 6,409,928

F3 · price: This transaction was executed in multiple trades at prices ranging from $26.46 to $27.20; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F4 · balance_after: Held directly by the Fund.

F4 · ownership.nature: Held directly by the Fund.

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-23-037172 · tm2310680-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: No plan indicated

Ownership: Indirect · See Footnotes

Disclosed balance after: 6,217,593

F1 · price: This transaction was executed in multiple trades at prices ranging from $26.29 to $27.20; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes, upon request, to provide full information to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected.

F2 · balance_after: Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund").

F2 · ownership.nature: Held directly by the RA Capital Healthcare Fund, L.P. (the "Fund").

F8 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-120780 · tm2231060-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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 · 426,302 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 November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

F1 · derivative.exercise_date: On November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

F1 · derivative.expiration_date: On November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

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

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

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-120780 · tm2231060-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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 · 994,706 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 November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

F1 · derivative.exercise_date: On November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

F1 · derivative.expiration_date: On November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. 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").

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-120780 · tm2231060-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 426,302

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 November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. The shares had no expiration date.

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

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

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-120780 · tm2231060-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 4,384,206

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").

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-120780 · tm2231060-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 994,706

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 November 17, 2022 each share of Series B Preferred Stock (the "Preferred Stock") converted into Common Stock of the Issuer at a ratio of 1-for-2.466 upon closing of the initial public offering of the Issuer's common stock without payment of further consideration. 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").

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-119645 · tm2230749-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 35,235

Underlying: Common Stock · 35,235 shares

Expires 2032-11-13

F2 · derivative.exercise_date: The shares subject to the option shall vest in 36 equal monthly installments starting on October 12, 2022 ("Vesting Commencement Date"), such that all shares are fully vested on the third anniversary of the Vesting Commencement Date, in each case subject to Dr. Derek DiRocco's continuous service through each such vesting date.

F1 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F2 · ownership.nature: The shares subject to the option shall vest in 36 equal monthly installments starting on October 12, 2022 ("Vesting Commencement Date"), such that all shares are fully vested on the third anniversary of the Vesting Commencement Date, in each case subject to Dr. Derek DiRocco's continuous service through each such vesting date.

F3 · ownership.nature: Dr. Derek DiRocco is a Partner of the Adviser who serves on the Issuer's board of directors. Under Dr. DiRocco's arrangement with the Adviser, Dr. DiRocco holds the option for the benefit of the Fund and the Nexus Fund II. Dr. DiRocco 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 the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.

SEC source: 0001104659-22-117290 · tm2230267-2_4.xml · nonDerivative · entry 2

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 902,904

F3 · price: Received in exchange for 763,942 shares of common stock of ARS pursuant to the Merger Agreement. Under the terms of the Merger Agreement, on November 8, 2022, Merger Sub merged with and into ARS (the "Merger"), with ARS surviving the Merger as a wholly-owned subsidiary of the Issuer. Upon the closing of the Merger, each share of ARS common stock was converted into the right to receive 1.1819 shares of the Issuer common stock. Subsequent to the Merger, the name of the Issuer was changed from Silverback Therapeutics, Inc. to ARS Pharmaceuticals, Inc.

F4 · balance_after: These shares are held directly by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F4 · ownership.nature: These shares are held directly by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-117290 · tm2230267-2_4.xml · nonDerivative · entry 1

RA CAPITAL MANAGEMENT, L.P. · CIK 0001346824 · Director

RA Capital Healthcare Fund LP · CIK 0001315082 · Director

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · Director

Kolchinsky Peter · CIK 0001384859 · Director

Shah Rajeev M. · CIK 0001619841 · Director

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See Footnotes

Disclosed balance after: 2,106,774

F1 · price: Received in exchange for 1,782,531 shares of common stock of ARS Pharmaceuticals, Inc. ("ARS") pursuant to an Agreement and Plan of Merger and Reorganization by and among ARS, the Issuer and Sabre Merger Sub, Inc., a wholly-owned subsidiary of the Issuer ("Merger Sub"), as amended (the "Merger Agreement"). Under the terms of the Merger Agreement, on November 8, 2022, Merger Sub merged with and into ARS (the "Merger"), with ARS surviving the Merger as a wholly-owned subsidiary of the Issuer. Upon the closing of the Merger, each share of ARS common stock was converted into the right to receive 1.1819 shares of the Issuer common stock. Subsequent to the Merger, the name of the Issuer was changed from Silverback Therapeutics, Inc. to ARS Pharmaceuticals, Inc.

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

F2 · ownership.nature: These shares 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 II. 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: 0001104659-22-110000 · tm2228572-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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 Footenotes

Disclosed balance after: 6,848,911

F1 · balance_after: 6,062,504 shares are held directly by the RA Capital Healthcare Fund, L.P (the "Fund") and 786,407 sahres are held directly by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F1 · ownership.nature: 6,062,504 shares are held directly by the RA Capital Healthcare Fund, L.P (the "Fund") and 786,407 sahres are held directly by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-086686 · tm2222743-1_4seq1.xml · nonDerivative · entry 2

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnote

Disclosed balance after: 3,773,517

F3 · balance_after: These securities include 3,357,905 shares held directly by the Fund and 415,612 shares held by the Nexus Fund II.

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-086686 · tm2222743-1_4seq1.xml · nonDerivative · entry 1

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,773,417

F2 · price: This transaction was executed in multiple trades at prices ranging from $7.34 to $7.68; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected upon request to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer.

F1 · balance_after: These securities include 3,357,805 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F1 · ownership.nature: These securities include 3,357,805 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-083728 · tm2222103-1_4seq1.xml · nonDerivative · entry 2

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,771,608

F4 · price: This transaction was executed in multiple trades at prices ranging from $7.67 to $8.00; the price reported above reflects the weighted average purchase price.

F3 · balance_after: These securities include 3,355,996 shares held directly by the Fund and 415,612 shares held by the Nexus Fund II.

F3 · ownership.nature: These securities include 3,355,996 shares held directly by the Fund and 415,612 shares held by the Nexus Fund II.

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-083728 · tm2222103-1_4seq1.xml · nonDerivative · entry 1

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,763,327

F2 · price: This transaction was executed in multiple trades at prices ranging from $7.43 to $7.92; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected upon request to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer.

F1 · balance_after: These securities include 3,347,715 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F1 · ownership.nature: These securities include 3,347,715 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F5 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-073920 · tm2219316-1_4seq1.xml · nonDerivative · entry 1

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,748,389

F2 · price: This transaction was executed in multiple trades at prices ranging from $7.99 to $8.00; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected upon request to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer.

F1 · balance_after: These securities include 3,332,777 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F1 · ownership.nature: These securities include 3,332,777 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F3 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-072982 · tm2218907-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 25,000

Underlying: Common Stock · 25,000 shares

Expires 2032-06-14

F2 · derivative.exercise_date: The shares subject to the option will vest on on the earlier of June 15, 2023 or the 2023 annual stockholder meeting, subject to Laura Stoppel's continuous service through each such vesting date.

F1 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund"),RA Capital Nexus Fund II, L.P. (the "Nexus Fund II") and a separately managed account (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.

F2 · ownership.nature: The shares subject to the option will vest on on the earlier of June 15, 2023 or the 2023 annual stockholder meeting, subject to Laura Stoppel's continuous service through each such vesting date.

F3 · ownership.nature: Laura Stoppel is a Principal of the Adivser who serves on the Issuer's board of directors. Under Ms. Stoppel's arrangement with the Adviser, Ms. Stoppel holds the option for the benefit of the Fund, the Nexus Fund II and the Account. Ms. Stoppel 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, the Nexus Fund II, and the Account to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock.

SEC source: 0001104659-22-071465 · tm2218531-1_4seq1.xml · nonDerivative · entry 2

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,748,087

F2 · price: This transaction was executed in multiple trades at prices ranging from $7.725 to $8.00; the price reported above reflects the weighted average purchase price. The reporting person hereby undertakes to provide full information regarding the number of shares and prices at which these transactions, and all other transactions reported in this Form 4, were effected upon request to the staff of the Securities and Exchange Commission, the Issuer, or a security holder of the Issuer.

F3 · balance_after: These securities include 3,332,475 shares held directly by the Fund and 415,612 shares held by Nexus Fund II.

F3 · ownership.nature: These securities include 3,332,475 shares held directly by the Fund and 415,612 shares held by Nexus Fund II.

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-071465 · tm2218531-1_4seq1.xml · nonDerivative · entry 1

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

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

RA Capital Nexus Fund II, L.P. · CIK 0001825376 · 10% owner

Kolchinsky Peter · CIK 0001384859 · 10% owner

Shah Rajeev M. · CIK 0001619841 · 10% owner

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

10b5-1 filing: Not disclosed

Ownership: Indirect · See footnotes

Disclosed balance after: 3,686,663

F1 · balance_after: These securities include 3,271,051 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F1 · ownership.nature: These securities include 3,271,051 shares held directly by RA Capital Healthcare Fund, L.P. (the "Fund") and 415,612 shares held by RA Capital Nexus Fund II, L.P. (the "Nexus Fund II").

F4 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for the Fund and the Nexus Fund II. 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: 0001104659-22-071026 · tm2218398-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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 footnote

Disclosed balance after: 22,278

Underlying: Common Stock · 22,278 shares

Expires 2032-06-09

F6 · derivative.exercise_date: The option shall vest in substantially equal monthly installments over the twelve (12) months following the date of grant (or, in the event the next annual meeting of the Company's stockholders occurs prior to the first anniversary of the date of grant, any remaining unvested portion of the option will vest on the date of such annual meeting of the Company's stockholders), subject to Dr. Kolchinsky's continued service through the applicable vesting date.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky holds the option and restricted stock units for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash or stock received upon sale of the common stock underlying the option and restricted stock units, which will offset advisory fees owed by the Fund and the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and restricted stock units and respective underlying common stock except to the extent of their pecuniary interest.

SEC source: 0001104659-22-071026 · tm2218398-1_4seq1.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 II, L.P. · CIK 0001825376 · Director · 10% owner

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 footnote

Disclosed balance after: 5,543

F1 · shares: These shares represent restricted stock units and will be settled into common stock upon vesting. Each restricted stock unit would be converted into one share of ICVX common stock. These restricted stock units shall vest at the earlier of the first anniversary of the grant date or the date of the next annual meeting of the Company's stock holders, subject to the continued service of Dr. Peter Kolchinsky's service on the Issuer's board of directors through the vesting date.

F1 · ownership.nature: These shares represent restricted stock units and will be settled into common stock upon vesting. Each restricted stock unit would be converted into one share of ICVX common stock. These restricted stock units shall vest at the earlier of the first anniversary of the grant date or the date of the next annual meeting of the Company's stock holders, subject to the continued service of Dr. Peter Kolchinsky's service on the Issuer's board of directors through the vesting date.

F2 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F3 · ownership.nature: Under Dr. Kolchinsky's arrangement with the Adviser, Dr. Kolchinsky holds the option and restricted stock units for the benefit of the Fund and the Nexus Fund II. Dr. Kolchinsky is obligated to turn over to the Adviser any net cash or stock received upon sale of the common stock underlying the option and restricted stock units, which will offset advisory fees owed by the Fund and the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and restricted stock units and respective underlying common stock except to the extent of their pecuniary interest.

SEC source: 0001104659-22-069399 · tm2218000-1_4seq1.xml · derivative · 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 II, L.P. · CIK 0001825376 · Director · 10% owner

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: 21,250

Underlying: Common Stock · 21,250 shares

Expires 2032-06-06

F2 · derivative.exercise_date: The shares subject to the option will vest on the earlier of: (i) the one-year anniversary of the grant date and (ii) the subsequent annual meeting of stockholders, subject to Mr. Jake Simson's, a Partner of the Adviser who serves on the Issuer's board of directors, continued service as a director.

F1 · ownership.nature: RA Capital Management, L.P. (the "Adviser") is the investment manager for RA Capital Healthcare Fund, L.P. (the "Fund") and RA Capital Nexus Fund II, L.P. (the "Nexus Fund II"). 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.

F2 · ownership.nature: The shares subject to the option will vest on the earlier of: (i) the one-year anniversary of the grant date and (ii) the subsequent annual meeting of stockholders, subject to Mr. Jake Simson's, a Partner of the Adviser who serves on the Issuer's board of directors, continued service as a director.

F3 · ownership.nature: Under Mr. Simson's arrangement with the Adviser, Mr. Simson holds the option for the benefit of the Fund and the Nexus Fund II. Mr. Simson 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 the Nexus Fund II to the Adviser. The Reporting Persons therefore disclaim beneficial ownership of the option and underlying common stock except to the extent of their pecuniary interest.