PEPG

SEC source: 0001127602-23-018040 · form4.xml · nonDerivative · entry 3

McArthur James G · CIK 0001763307 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 500

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 8, 2022.

SEC source: 0001127602-23-018040 · form4.xml · derivative · entry 5

McArthur James G · CIK 0001763307 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 354,504

Underlying: Common Stock · 1,800 shares

Expires 2031-03-21

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 8, 2022.

F4 · derivative.exercise_date: This stock option vests over four years following the vesting commencement date (January 21, 2021) with 25% of such shares vesting on the first anniversary of the vesting commencement date, and the remaining shares vesting in 36 equal monthly installments, subject to continued service through each vesting date.

SEC source: 0001127602-23-018040 · form4.xml · nonDerivative · entry 2

McArthur James G · CIK 0001763307 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 8, 2022.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.00 to $16.14, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0001127602-23-018040 · form4.xml · nonDerivative · entry 1

McArthur James G · CIK 0001763307 · Director · President and CEO

10b5-1 filing: Plan reported

Ownership: Direct

Disclosed balance after: 1,800

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 8, 2022.

SEC source: 0001127602-23-011535 · form4.xml · derivative · entry 3

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 143,804

Underlying: Common Stock · 392 shares

Expires 2031-11-10

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

F2 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-011535 · form4.xml · nonDerivative · entry 2

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-23-011535 · form4.xml · nonDerivative · entry 1

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 392

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-23-008414 · form4.xml · derivative · entry 2

Mellion Michelle L · CIK 0001923040 · SVP, Clinical Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 95,000

Underlying: Common Stock · 20,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-008414 · form4.xml · derivative · entry 1

Mellion Michelle L · CIK 0001923040 · SVP, Clinical Development

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 75,000

Underlying: Common Stock · 75,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-008395 · form4.xml · derivative · entry 1

Svenstrup Niels · CIK 0001922541 · SVP, Chem. Mfg & Controls

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 75,000

Underlying: Common Stock · 75,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-008405 · form4.xml · derivative · entry 1

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 75,000

Underlying: Common Stock · 75,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-008373 · form4.xml · derivative · entry 1

Donnelly Noel · CIK 0001922546 · Chief Financial Officer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 144,000

Underlying: Common Stock · 144,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-008382 · form4.xml · derivative · entry 1

McArthur James G · CIK 0001763307 · Director · President and CEO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 275,000

Underlying: Common Stock · 275,000 shares

Expires 2033-02-28

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001127602-23-004055 · form4.xml · derivative · entry 9

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 144,196

Underlying: Common Stock · 644 shares

Expires 2031-11-10

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

F4 · derivative.exercise_date: This stock option vests over four years following the vesting commencement date (October 15, 2021) with 25% of such shares vesting on the first anniversary of the vesting commencement date, and the remaining shares vesting in 36 equal monthly installments, subject to continued service through each vesting date.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 6

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 5

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 644

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-23-004055 · form4.xml · derivative · entry 8

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 144,840

Underlying: Common Stock · 3,679 shares

Expires 2031-11-10

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

F4 · derivative.exercise_date: This stock option vests over four years following the vesting commencement date (October 15, 2021) with 25% of such shares vesting on the first anniversary of the vesting commencement date, and the remaining shares vesting in 36 equal monthly installments, subject to continued service through each vesting date.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 4

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

F3 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $17.00 to $17.35, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 3

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,679

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-23-004055 · form4.xml · derivative · entry 7

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 148,519

Underlying: Common Stock · 1,677 shares

Expires 2031-11-10

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

F4 · derivative.exercise_date: This stock option vests over four years following the vesting commencement date (October 15, 2021) with 25% of such shares vesting on the first anniversary of the vesting commencement date, and the remaining shares vesting in 36 equal monthly installments, subject to continued service through each vesting date.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 2

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

F1 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

F2 · price: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $17.00 to $17.12, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

SEC source: 0001127602-23-004055 · form4.xml · nonDerivative · entry 1

Goyal Jaya · CIK 0001922548 · EVP, Res. & Preclin. Dev.

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,677

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 · kind: The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 6, 2022.

SEC source: 0001127602-22-027831 · form4.xml · derivative · entry 2

Svenstrup Niels · CIK 0001922541 · SVP, Chem. Mfg & Controls

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 25,629

Underlying: Common Stock · 10,000 shares

Expires 2031-04-20

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_date: This stock option vests over four years following the vesting commencement date (April 1, 2021) with 25% of such shares vesting on the first anniversary of the vesting commencement date, and the remaining shares vesting in 36 equal monthly installments, subject to continued service through each vesting date.

SEC source: 0001127602-22-027831 · form4.xml · nonDerivative · entry 1

Svenstrup Niels · CIK 0001922541 · SVP, Chem. Mfg & Controls

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,000

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

SEC source: 0000899243-22-032433 · doc4.xml · derivative · entry 1

Dable Habib J · CIK 0001690773 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,686

Underlying: Common Stock · 22,686 shares

Expires 2032-10-02

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on September 20, 2023 and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0000899243-22-030121 · doc4.xml · derivative · entry 1

Mellion Michelle L · CIK 0001923040 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 100,000

Underlying: Common Stock · 100,000 shares

Expires 2032-06-29

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on April 4, 2023, and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · derivative · entry 6

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Private Design Fund V, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 268,480 shares

Expires not disclosed

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

F1 · derivative.exercise_price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · derivative.exercise_date: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · derivative.expiration_date: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · derivative · entry 5

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Partners, L.P.

Disclosed balance after: 0

Underlying: Common Stock · 268,480 shares

Expires not disclosed

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

F1 · derivative.exercise_price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · derivative.exercise_date: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F1 · derivative.expiration_date: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · nonDerivative · entry 4

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Private Design Fund V, L.P.

Disclosed balance after: 476,813

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · nonDerivative · entry 3

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Partners, L.P.

Disclosed balance after: 476,813

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · nonDerivative · entry 2

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Private Design Fund V, L.P.

Disclosed balance after: 268,480

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

F1 · price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0001193805-22-000766 · e621642_4-pepgen.xml · nonDerivative · entry 1

Flynn James E · CIK 0001352546 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt L.P. · CIK 0001010823 · 10% owner · Possible Member of 10% Group

DEERFIELD PARTNERS, L.P. · CIK 0001301041 · 10% owner · Possible Member of 10% Group

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) · CIK 0001009258 · 10% owner · Possible Member of 10% Group

Deerfield Mgmt V, L.P. · CIK 0001876688 · 10% owner · Possible Member of 10% Group

Deerfield Private Design Fund V, L.P. · CIK 0001815437 · 10% owner · Possible Member of 10% Group

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

10b5-1 filing: Not disclosed

Ownership: Indirect · Through Deerfield Partners, L.P.

Disclosed balance after: 268,480

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

F1 · price: Each share of Series B Preferred Stock automatically converted into 0.98232 shares of the Issuer's common stock upon the closing of the Issuer's initial public offering (on an adjusted basis after giving effect to the 1-for-1.018 reverse split of the Issuer's common stock effected by the Issuer on April 29, 2022).

F2 · ownership.nature: This Form 4 is being filed by the undersigned as well as the entities listed on the Joint Filer Information Statement attached as an exhibit hereto (the "Reporting Persons"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (the "Fund"). Deerfield Mgmt V, L.P. is the general partner of Deerfield Private Design Fund V, L.P. ("Fund V"). Deerfield Mgmt, L.P. is the general partner of Deerfield Partners, L.P. (together with Fund V, the "Funds"). Deerfield Management Company, L.P. is the investment manager of the Funds. James E. Flynn is the sole member of the general partner of each of Deerfield Mgmt V, L.P., Deerfield Mgmt, L.P. and Deerfield Management Company, L.P.

F3 · ownership.nature: In accordance with Instruction 4(b)(iv) to Form 4, the entire amount of the Issuer's securities held by the Fund is reported herein. For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, each Reporting Person disclaims beneficial ownership of any such securities, except to the extent of his/its indirect pecuniary interest therein, if any, and this report shall not be deemed an admission that such Reporting Person is the beneficial owner of such securities for purposes of Section 16 or otherwise.

SEC source: 0000899243-22-017488 · doc4.xml · derivative · entry 6

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,547,713 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 May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.exercise_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.expiration_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0000899243-22-017488 · doc4.xml · derivative · entry 5

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 945,859 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 May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.exercise_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.expiration_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0000899243-22-017488 · doc4.xml · derivative · entry 4

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 0

Underlying: Common Stock · 1,262,986 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 May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.exercise_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

F1 · derivative.expiration_date: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0000899243-22-017488 · doc4.xml · nonDerivative · entry 3

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 3,875,418

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 · shares: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0000899243-22-017488 · doc4.xml · nonDerivative · entry 2

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,327,705

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 · shares: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0000899243-22-017488 · doc4.xml · nonDerivative · entry 1

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,381,846

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 · shares: On May 10, 2022, each share of Series A-1 Preferred Stock, Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of Common Stock of the Issuer on a 1.018-for-1 basis without payment of further consideration upon closing of the initial public offering of the Issuer's Common Stock. The shares of Preferred Stock had no expiration date.

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · derivative · entry 10

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 · 634,878 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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

F3 · ownership.nature: These securities are held directly by the 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, the Nexus Fund II and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · derivative · entry 9

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 · 1,481,383 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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

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

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

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · derivative · entry 8

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

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

RA Capital Nexus Fund 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 · 207,672 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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

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

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

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · derivative · entry 7

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

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

RA Capital Nexus Fund 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 · 417,973 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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

F3 · ownership.nature: These securities are held directly by the 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, the Nexus Fund II and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · derivative · entry 6

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

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

RA Capital Nexus Fund 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 · 2,160,846 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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.exercise_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F1 · derivative.expiration_date: On May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

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

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

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · nonDerivative · 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: 207,672

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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

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

SEC source: 0001104659-22-059645 · tm2215415-1_4seq1.xml · nonDerivative · entry 4

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

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

RA Capital Nexus Fund 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: 1,302,600

F3 · ownership.nature: These securities are held directly by the 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, the Nexus Fund II and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-22-059645 · tm2215415-1_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: 1,052,851

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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

F3 · ownership.nature: These securities are held directly by the 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, the Nexus Fund II and the Account. The general partner of the Adviser is RA Capital Management GP, LLC (the "Adviser GP"), of which Dr. Peter Kolchinsky and Mr. Rajeev Shah are the managing members. The Adviser, the Adviser GP, Dr. Kolchinsky, and Mr. Shah disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein.

SEC source: 0001104659-22-059645 · tm2215415-1_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: 6,621,680

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

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

SEC source: 0001104659-22-059645 · tm2215415-1_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: 3,642,229

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 May 6, 2022, each share of Series A-2 Preferred Stock and Series B Preferred Stock (collectively, the "Preferred Stock") converted into shares of the Issuer's common stock at a ratio of 1.018-for-1 without payment of further consideration upon closing of the initial public offering of the Issuer's common stock. The shares had no expiration date.

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

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

SEC source: 0000950170-24-043058 · ownership.xml · nonDerivative · entry 1

Oxford Science Enterprises plc · CIK 0001856079 · 10% owner

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 4,755,388

SEC source: 0000899243-22-017500 · doc4.xml · derivative · entry 1

Mellion Michelle L · CIK 0001923040 · See Remarks

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,655

Underlying: Common Stock · 16,655 shares

Expires 2032-05-05

F1 · derivative.exercise_date: This option shall vest as follows: twenty-five percent (25%) on the one-year anniversary of the Grant Date and the remainder vesting in thirty-six (36) equal monthly installments, subject to the option recipient's continued service or employment with the Company on each applicable vesting date.