The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Fund II, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

The percentage set forth in row (13) is based on the 87,476,338 shares of common stock, par value $0.001 per share (“Common Stock”), of Allakos Inc., a Delaware corporation (the “Issuer”), reported by the Issuer to be outstanding as of November 7, 2023 on the Issuer’s Form 10-Q, filed with the Securities and Exchange Commission (“SEC”) on November 13, 2023.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Fund II (Ohio), L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners II (Ohio), LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽²⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽²⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽²⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by RiverVest Venture Fund II (Ohio), L.P., a Delaware limited partnership (“RiverVest II (Ohio)”). RiverVest Venture Partners II (Ohio), LLC, a Delaware limited liability company (“RiverVest Partners II (Ohio)”), is the general partner of RiverVest II (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners II, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽³⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽³⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽³⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

Represents shares of Common Stock owned by RiverVest Venture Fund II, L.P., a Delaware limited partnership (“RiverVest II”), and shares of Common Stock owned by RiverVest II (Ohio). RiverVest Venture Partners II, L.P., a Delaware limited partnership (“RiverVest Partners II”), is the general partner of RiverVest II and the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners II, LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁴⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁴⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁴⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by RiverVest II and shares of Common Stock owned by RiverVest II (Ohio). RiverVest Venture Partners II, LLC, a Delaware limited liability company, is the general partner of RiverVest Partners II, which is (a) the general partner of RiverVest II and (b) the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Fund III, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Fund III (Ohio), L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners III (Ohio), LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁵⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁵⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁵⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by RiverVest Venture Fund III (Ohio), L.P., a Delaware limited partnership (“RiverVest III (Ohio)”). RiverVest Venture Partners III (Ohio), LLC, a Delaware limited liability company (“RiverVest Partners III (Ohio)”), is the general partner of RiverVest III (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners III, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁶⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁶⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁶⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

Represents shares of Common Stock owned by RiverVest Venture Fund III, L.P., a Delaware limited partnership (“RiverVest III”), and shares of Common Stock owned by RiverVest III (Ohio). RiverVest Venture Partners III, L.P., a Delaware limited partnership (“RiverVest Partners III”), is the general partner of RiverVest III and the sole member of RiverVest Partners III (Ohio), which is the general partner of RiverVest III (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest Venture Partners III, LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁷⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁷⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁷⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by RiverVest III and shares of Common Stock owned by RiverVest III (Ohio). RiverVest Venture Partners III, LLC, a Delaware limited liability company, is the general partner of RiverVest Partners III, which is (a) the general partner of RiverVest III and (b) the sole member of RiverVest Partners III (Ohio), which is the general partner of RiverVest III (Ohio).

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 3x5 RiverVest Fund II, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 3x5 RiverVest Fund II-B, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 WC

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 3x5 RiverVest Partners II, LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁸⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁸⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁸⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by 3x5 RiverVest Fund II, L.P., a Delaware limited partnership (“3x5 RiverVest II”), and shares of Common Stock owned by 3x5 RiverVest Fund II-B, L.P., a Delaware limited partnership (“3x5 RiverVest II-B”). 3x5 RiverVest Partners II, LLC, a Delaware limited liability company (“3x5 RiverVest Partners”), is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest 3x5 Managers II, L.P.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽⁹⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽⁹⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽⁹⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 PN

Represents shares of Common Stock owned by 3x5 RiverVest II and shares of Common Stock owned by 3x5 RiverVest II-B. RiverVest 3x5 Managers II, L.P., a Delaware limited partnership (“RiverVest 3x5 Managers”), is one of two members of 3x5 RiverVest Partners, which is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 RiverVest 3x5 Managers II, LLC

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 Delaware, USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 0

 SHARED VOTING POWER

 0⁽¹⁰⁾

 SOLE DISPOSITIVE POWER

 0

 SHARED DISPOSITIVE POWER

 0⁽¹⁰⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 0⁽¹⁰⁾

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.0%⁽¹⁾

 TYPE OF REPORTING PERSON

 OO

Represents shares of Common Stock owned by 3x5 RiverVest II and shares of Common Stock owned by 3x5 RiverVest II-B. RiverVest 3x5 Managers II, LLC, a Delaware limited liability company (“RiverVest 3x5 Managers II”), is the general partner of RiverVest 3x5 Managers, which is one of two members of 3x5 RiverVest Partners. 3x5 RiverVest Partners is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 John P. McKearn, Ph.D.

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 108,159⁽¹¹⁾

 SHARED VOTING POWER

 0⁽¹²⁾

 SOLE DISPOSITIVE POWER

 108,159⁽¹¹⁾

 SHARED DISPOSITIVE POWER

 0⁽¹²⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 108,159

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.2%⁽¹⁾

 TYPE OF REPORTING PERSON

 IN

Represents 108,159 shares of Common Stock held directly by Dr. McKearn.

Represents shares of Common Stock owned by RiverVest II, shares of Common Stock owned by RiverVest II (Ohio), shares of Common Stock owned by RiverVest III, shares of Common Stock owned by RiverVest III (Ohio), shares of Common Stock owned by 3x5 RiverVest II and shares of Common Stock owned by 3x5 RiverVest II-B.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 Jay Schmelter

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 16,610⁽¹³⁾

 SHARED VOTING POWER

 0⁽¹⁴⁾

 SOLE DISPOSITIVE POWER

 16,610⁽¹³⁾

 SHARED DISPOSITIVE POWER

 0⁽¹⁴⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 16,610

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.02%⁽¹⁾

 TYPE OF REPORTING PERSON

 IN

Represents 11,766 shares of Common Stock held directly, 1,868 shares of Common Stock owned by RiverVest Venture Management LLC Profit Sharing Plan FBO Jay W. Schmelter, 1,488 shares of Common Stock owned by the Schmelter Family Trust dated 5/2/19 and 1,488 shares of Common Stock owned by the Schmelter Family Trust #2 dated 9/30/2019.

Represents shares of Common Stock owned by RiverVest II, shares of Common Stock owned by RiverVest II (Ohio), shares of Common Stock owned by RiverVest III, shares of Common Stock owned by RiverVest III (Ohio), shares of Common Stock owned by 3x5 RiverVest II and shares of Common Stock owned by 3x5 RiverVest II-B.

 NAME OF REPORTING PERSON

 I.R.S. IDENTIFICATION NO. (ENTITIES ONLY)

 Thomas C. Melzer

 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

 (a) ☐  (b) ☐

 SEC USE ONLY

 SOURCE OF FUNDS

 AF

 CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)

 ☐

 CITIZENSHIP OR PLACE OF ORGANIZATION

 USA

NUMBER OF

SHARES

 BENEFICIALLY 

OWNED BY

EACH

REPORTING

PERSON

WITH

 SOLE VOTING POWER

 21,476⁽¹⁵⁾

 SHARED VOTING POWER

 0⁽¹⁶⁾

 SOLE DISPOSITIVE POWER

 21,476⁽¹⁵⁾

 SHARED DISPOSITIVE POWER

 0⁽¹⁶⁾

 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

 21,476

 CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES

 ☐

 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

 0.03%⁽¹⁾

 TYPE OF REPORTING PERSON

 IN

Includes 10,738 shares of Common Stock owned by the Thomas C. Melzer Revocable Trust dtd 4/4/2002 and 10,738 shares of Common Stock owned by Melzer Family Trust dated 11/9/2006.

Represents shares of Common Stock owned by RiverVest II, shares of Common Stock owned by RiverVest II (Ohio), shares of Common Stock owned by RiverVest III, shares of Common Stock owned by RiverVest III (Ohio), shares of Common Stock owned by 3x5 RiverVest II and shares of Common Stock owned by 3x5 RiverVest II-B.

Entity

RiverVest Venture Fund II, L.P.

RiverVest Venture Fund II (Ohio), L.P.

RiverVest Venture Fund III, L.P.

RiverVest Venture Fund III (Ohio), L.P.

3x5 RiverVest Fund II, L.P.

3x5 RiverVest Fund II-B, L.P.

Entity or Individual

RiverVest Venture Fund II, L.P.

RiverVest Venture Fund II (Ohio), L.P.

RiverVest Venture Partners II (Ohio), LLC⁽¹⁾

RiverVest Venture Partners II, L.P.⁽²⁾

RiverVest Venture Partners II, LLC⁽³⁾

RiverVest Venture Fund III, L.P.

RiverVest Venture Fund III (Ohio), L.P.

RiverVest Venture Partners III (Ohio), LLC⁽⁴⁾

RiverVest Venture Partners III, L.P.⁽⁵⁾

RiverVest Venture Partners III, LLC⁽⁶⁾

3x5 RiverVest Fund II, L.P.

3x5 RiverVest Fund II-B, L.P.

3x5 RiverVest Partners II, LLC⁽⁷⁾

RiverVest 3x5 Managers II, L.P.⁽⁸⁾

RiverVest 3x5 Managers II, LLC⁽⁹⁾

John P. McKearn, Ph.D.⁽¹⁰⁾

Jay Schmelter⁽¹¹⁾

Thomas C. Melzer⁽¹²⁾

Based on the 87,476,338 shares of Common Stock reported by the Issuer to be outstanding as of November 7, 2023 on the Issuer’s Form 10-Q, filed with the SEC on November 13, 2023.

RiverVest Partners II (Ohio), as the general partner of RiverVest II (Ohio), may be deemed to beneficially own the shares of Common Stock owned by RiverVest II (Ohio).

RiverVest Partners II is the general partner of RiverVest II and the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio), and as a result, may be deemed to beneficially own the shares of Common Stock owned by RiverVest II and the shares of Common Stock owned by RiverVest II (Ohio).

RiverVest Venture Partners II, LLC, a Delaware limited liability company, is the general partner of RiverVest Partners II, which is (a) the general partner of RiverVest II and (b) the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio), and as a result, may be deemed to beneficially own the shares of Common Stock owned by RiverVest II and the shares of Common Stock owned by RiverVest II (Ohio).

RiverVest Partners III (Ohio) is the general partner of RiverVest III (Ohio), and as a result, may be deemed to beneficially own the shares of Common Stock owned by RiverVest III (Ohio).

RiverVest Partners III is the general partner of RiverVest III and the sole member of RiverVest Partners III (Ohio), which is the general partner of RiverVest III (Ohio), and as a result, may be deemed to beneficially own the shares of Common Stock owned by RiverVest III and the shares of Common Stock owned by RiverVest III (Ohio).

RiverVest Venture Partners III, LLC, a Delaware limited liability company, is the general partner of RiverVest Partners III, which is (a) the general partner of RiverVest III and (b) the sole member of RiverVest Partners III (Ohio), which is the general partner of RiverVest III (Ohio), and as a result, may be deemed to beneficially own the shares of Common Stock owned by RiverVest III and the shares of Common Stock owned by RiverVest III (Ohio).

3x5 RiverVest Partners is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B, and as a result, may be deemed to beneficially own the shares of Common Stock owned by 3x5 RiverVest II and the shares of Common Stock owned by 3x5 RiverVest II-B.

RiverVest 3x5 Managers is one of two members of 3x5 RiverVest Partners, which is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B, and as a result, may be deemed to beneficially own the shares of Common Stock owned by 3x5 RiverVest II and the shares of Common Stock owned by 3x5 RiverVest II-B.

RiverVest 3x5 Managers II is the general partner of RiverVest 3x5 Managers, which is one of two members of 3x5 RiverVest Partners. 3x5 RiverVest Partners is the general partner of 3x5 RiverVest II and 3x5 RiverVest II-B. As a result, RiverVest 3x5 Managers II may be deemed to beneficially own the shares of Common Stock owned by 3x5 RiverVest II and the shares of Common Stock owned by 3x5 RiverVest II-B.

Dr. McKearn is an authorized person of RiverVest Venture Partners II, LLC, a Delaware limited liability company, which is the general partner of RiverVest Partners II. RiverVest Partners II is (a) the general partner of RiverVest II and (b) the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio). As a result, Dr. McKearn may be deemed to beneficially own the shares of Common Stock owned by RiverVest II and the shares of Common Stock owned by RiverVest II (Ohio).

Mr. Schmelter is a member of RiverVest Venture Partners II, LLC, a Delaware limited liability company, which is the general partner of RiverVest Partners II. RiverVest Partners II is (a) the general partner of RiverVest II and (b) the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio). As a result, Mr. Schmelter may be deemed to beneficially own the shares of Common Stock owned by RiverVest II and the shares of Common Stock owned by RiverVest II (Ohio).

Mr. Melzer is a member of RiverVest Venture Partners II, LLC, a Delaware limited liability company, which is the general partner of RiverVest Partners II. RiverVest Partners II is (a) the general partner of RiverVest II and (b) the sole member of RiverVest Partners II (Ohio), which is the general partner of RiverVest II (Ohio). As a result, Mr. Melzer may be deemed to beneficially own the shares of Common Stock owned by RiverVest II and the shares of Common Stock owned by RiverVest II (Ohio).

Previously filed.