Browse EX-10 agreements

Certain identified information has been excluded from the exhibit by marking such portions with brackets (“[***]”) because it is both (i) not material and (ii) is the type of information that the registrant treats as private or confidential.

LIMITED RECOURSE GUARANTY

This LIMITED RECOURSE GUARANTY (this “Agreement”) dated as of July 8, 2026, is made by SPERO THERAPEUTICS, INC., a Delaware corporation (the “Guarantor”), in favor of HCR SPERO SPV, LLC, together with its successors and assigns, in its capacities as NPA Representative and RPA Representative for the benefit of the Note Purchasers and RPA Purchasers, respectively (in such capacities, the “Agent”). Capitalized terms used herein and not otherwise defined herein shall have the meanings set forth in the Note Purchase Agreement, Royalty Purchase Agreement or Issuer Contribution Agreement (each as defined below), as applicable; provided, that, if a term is defined in more than one such agreement, such term shall have the meaning assigned to it in the agreement expressly referenced herein or, if no agreement is expressly referenced, the meaning most consistent with the context and purpose of the provision in which such term is used.

RECITALS

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Certain identified information has been excluded from the exhibit by marking such portions with brackets (“[***]”) because it is both (i) not material and (ii) is the type of information that the registrant treats as private or confidential.

ROYALTY AND MILESTONE PAYMENT INTEREST PURCHASE AND SALE AGREEMENT

by and among

SPERO SPV, LLC,

as the Company,

THE ENTITIES MANAGED BY HEALTHCARE ROYALTY MANAGEMENT, LLC LISTED ON THE SIGNATURE PAGES HERETO, as the Purchasers

and

HCR SPERO SPV, LLC, as the Purchaser Representative

Dated July 8, 2026

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TABLE OF CONTENTS

		Page
ARTICLE I DEFINED TERMS AND RULES OF CONSTRUCTION		1

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Certain identified information has been excluded from the exhibit by marking such portions with brackets (“[***]”) because it is both (i) not material and (ii) is the type of information that the registrant treats as private or confidential.

NEITHER THIS DEBT INSTRUMENT NOR THE NOTES ISSUED IN CONNECTION HEREWITH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS. SUCH SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT PURPOSES AND MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT FILED UNDER SAID ACT AND ANY APPLICABLE STATE SECURITIES LAWS, UNLESS AN EXEMPTION FROM SUCH REGISTRATION IS AVAILABLE.

THE FOLLOWING INFORMATION IS PROVIDED PURSUANT TO TREAS. REG. SECTION 1.1275-3: THIS DEBT INSTRUMENT IS ISSUED WITH ORIGINAL ISSUE DISCOUNT. HOLDERS CAN OBTAIN INFORMATION REGARDING ISSUE PRICE, AMOUNT OF ORIGINAL ISSUE DISCOUNT, ISSUE DATE, AND YIELD TO MATURITY OF THIS DEBT INSTRUMENT BY CONTACTING THE TREASURER OF ISSUER AT: 675 Massachusetts Avenue, 14th Floor, Cambridge, MA 02139

NOTE PURCHASE AND GUARANTY AGREEMENT

Dated as of July 8, 2026

Between

SPERO SPV, LLC,

as Issuer,

SPERO HOLDINGS SPV, LLC,

as Holdings

and

HCR SPERO SPV, LLC,

as Purchaser Representative,

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TABLE OF CONTENTS

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Certain identified information has been excluded from the exhibit by marking such portions with brackets (“[***]”) because it is both (i) not material and (ii) is the type of information that the registrant treats as private or confidential.

COLLABORATIONANDLICENSEAGREEMENT

byandamong

SPERO THERAPEUTICS, INC.,

INNOVENT BIOLOGICS (SUZHOU) CO., LTD.,

and

FORTVITA BIOLOGICS (USA), INC.

datedasof July 8,2026

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TABLEOFCONTENTS

Article 1		DEFINITIONS	1
Article 2		GOVERNANCE	25
2.1		Alliance Managers	25
2.2		Committees	25
2.3		Scope of Governance	28
2.4		Joint Patent Committee	28
2.5		Discontinuation of Committees	29
2.6		Joint Global Study	29
Article 3		LICENSES; NON-COMPETITION, AND OPTION	29
3.1		License Grant to Licensee	29

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Restricted Stock Unit No.___________

SPERO THERAPEUTICS, INC.

Restricted Stock Unit Award Grant Notice

Restricted Stock Unit Award Grant under the Company’s

2026 Stock Incentive Plan

1.	Name and Address of Participant:

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Option No. _______

SPERO THERAPEUTICS, INC.

Stock Option Grant Notice

Stock Option Grant under the Company’s

2026 Stock Incentive Plan

1.	Name and Address of Participant:
2.	Date of Option Grant:
3.	Type of Grant:
4.	Maximum Number of Shares for which this Option is exercisable:
5.	Exercise (purchase) price per share:
6.	Option Expiration Date:
7.	Vesting Start Date:

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Exhibit 10.23.1^

AMENDMENT NO. 1 TO PURCHASE AGREEMENT

AMENDMENT NO. 1 TO PURCHASE AGREEMENT, dated as of May 20, 2026 (this “Amendment”), by and among LONGEVERON INC., a Delaware corporation (the “Company”), and each of the entities (each, an “Investor”and together, the “Investors”) listed on Exhibit A attached to that certain Purchase Agreement, dated as of March 10, 2026, by and among the Company and the Investors (the “Purchase Agreement”). Capitalized terms used and not otherwise defined herein have the meanings ascribed thereto in the Purchase Agreement.

RECITALS

A.The Company and the Investors entered into the Purchase Agreement, pursuant to which, among other things, the Company agreed to sell, and the Investors agreed to purchase, certain Securities and the PRV Interest on the terms and conditions set forth therein.

B. The Company and the Investors desire to amend the Purchase Agreement in order to, among other things, clarify the Investors’ rights and interests with respect to the PRV Interest in connection with a potential transfer of the Company’s laromestrocel program for Hypoplastic Left Heart Syndrome.

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Exhibit 10.22.1

LONGEVERON INC.

AMENDMENT NO. 1 TO AT THE MARKET OFFERING AGREEMENT

June 16, 2026

H.C. Wainwright & Co., LLC

430 Park Avenue

New York, NY 10022 Ladies and Gentlemen:

Reference is made to the At the Market Offering Agreement, dated September 19, 2025 (the “SalesAgreement”), by and between Longeveron Inc., a Delaware corporation (the “Company”), and H.C. Wainwright & Co., LLC (the “Manager”). Capitalized terms used herein but not otherwise defined are used herein as defined in the Sales Agreement.

The Company and the Manager (collectively, the “Parties”) wish to amend the Agreement, to be effective as of the date hereof, pursuant to Section 14 of the Sales Agreement, on the terms and conditions set forth in this letter (this “Amendment”). Therefore, for and in consideration of the mutual covenants and agreements herein contained, and contained in the Sales Agreement, the Company, on the one hand, and the Manager, on the other hand, the Parties therefore hereby agree as follows:

1.

The final sentence of Section 3(jj) of the Agreement is hereby amended and restated in its entirety to read as follows:

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Exhibit 10.1#

June 30th, 2026

Dear Marie:

This letter agreement (this “Agreement”) sets forth the terms and conditions of your (referred to as “you” or “your” or “executive”) employment with Longeveron Inc. (the “Company”), which shall be effective as of July 13, 2026 (the “Effective Date”). This Agreement will govern your employment with the Company following the Effective Date on the following terms and conditions:

1.

Term.The term of your employment with the Company will terminate upon delivery to you by the Company of notice to such effect, which notice may be given for any or no reason, or upon your earlier resignation, death or Disability. You acknowledge that no provision contained in this Agreement will entitle you to remain in the employment of the Company for any specific period of time or affect the right of the Company to terminate your employment hereunder at any time for any reason, subject to compliance with the termination provisions set forth herein. The period during which you are employed by the Company pursuant to this Agreement shall be referred to as the “Term.” For purposes of this Agreement, “Disability” shall mean your inability, due to physical or mental incapacity, to perform the essential functions of your job, for one hundred eighty (180) days out of any three hundred sixty-five (365) day period or one hundred twenty (120) consecutive days or receiving any disability benefits under a Company plan for a period of one hundred twenty (120) consecutive days or longer.

2.

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AMENDMENT AGREEMENT

t****o the Memorandum of Understanding dated 12 October 2022

This Amendment Agreement (this “Amendment”) is made as of 30 August 2024 by and between:

	(1)	CUBEBIO Co., Ltd., a company incorporated under the laws of Republic of Korea having its office at 8F HYHILL Building, Digital-ro 10-gil 9, Geumcheon-gu, Seoul, Korea; and

	(2)	Jacob****son Medical (Hong Kong) Limited, a company incorporated under the laws of Hong Kong having its office at 13/F and 15/F, China Trade Centre, No. 122-124 Wai Yip Street, Kwun Tong, Kowloon, Hong Kong.

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Memorandum of Understanding This Memorandum of Understanding ( " MOU") is made as of 12 October 2022 by and between: (1) CUBEBIO Co . , Ltd . , a company incorporated under the laws of Republic of Korea having its office at 8 F Shinhan Life Bldg , Digital - ro 10 - gil 9 , Geumcheon - gu , Seoul Korea ; and (2) Jacobson Medical (Hong Kong) Limited, a company incorporated under the laws of Hong Kong having its office at 13 /F and 15 /F , China Trade Centre , No . 122 - 124 Wai Yip Street , Kwun Tong , Kowloon , Hong Kong The parties set out under (I) and (2) above are hereinafter collectively referred to as the "Parties " and individually as a "Party". WHEREAS the Parties intend to enter into a licence and supply agreement for certain products developed or manufactured by CUBEBIO , subject to the agreement and signing by the Parties of a detailed legally binding agreement ("Formal Agreement " ) ; The Parties have agreed as follows: - 1. Purpose . This MOU serves to confirm and memorialise both Parties' intention to commence good - faith negotiations of the provision of the Formal Agreement, including but not limited to the supply price and non - binding sales forecast as set out below for reference : - 1. Supply price i. Purine Metabolite Assay Kit: USD 300 / vial (30 tests / vial) ii. CEED - SA0 : Device USD 99 / unit , Sensor USD I 0 / unit iii. CEED - D USD 350/bottle (100 tests/bottle) 2. N on - b m ' d m ' g 3 - year sa 1 es £ orecast £ or sa 1 e . s m H ong K ongan dM acau Total Year3 Year2 Year 1 Item 1 , 800 vials 1 , 000 vials 500 Vials 300 Vials Purine Metabolite

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AMENDMENT NO. 1 TO DISTRIBUTORSHIP AGREEMENT

between Taiwan Biotech Co., Ltd. and CUBEBIO Co., Ltd.

THIS AMENDMENT NO. 1 (the “Amendment”), effective as of 15th April 2026 (the “Amendment Effective Date”), is entered into between:

	(A)	Taiwan Biotech Co., Ltd., a company incorporated under the laws of Taiwan and having its office at 22, Jie-Shou Rd., Taoyuan City, Taiwan, R.O.C. and its related affiliates hereinafter collectively called (“TBC”);

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