AMENDMENT #2 TO PROJECT RIDER #1 COLLABORATION AGREEMENT

Exhibit 10.10.4

AMENDMENT #2

TO

PROJECT RIDER #1

COLLABORATION AGREEMENT

This Amendment #2 to Project Rider #1 (“Amendment #2”) is entered into effective as of the date of the final signature executing this Amendment #2 (“Amendment #2 Effective Date”) by and between Magenta Therapeutics, Inc. (“Magenta”) and National Marrow Donor Program d/b/a Be The Match Biotherapies (“BTMB”) (each a “Party” and collectively the “Parties”).

WHEREAS, the Parties executed a Collaboration Agreement, effective November 10, 2017 and a Project Rider, effective December 6, 2017 (as amended by that certain Amendment #1, effective December 6, 2018, “Project Rider #1”); and

WHEREAS, the Parties agree to revise the Payment Schedule of the Project Rider #1.

NOW, THEREFORE, for the valuable consideration contained herein, and intending to be legally bound, Magenta and BTMB agree to the following amendment to be effective as of the Amendment #2 Effective Date as follows:

Amendment to Project Rider #1

1. Delete the Payment Schedule in Section D. Compensation of BTMB of Project Rider #1 in its entirety and replace it with the following to read as follows:

PAYMENT SCHEDULE

For Services provided by BTMB during Calendar Year 2020 (January 1, 2020 through December 31, 2020), Magenta will pay BTMB a fixed price quarterly payment of $25,000. BTMB will invoice $25,000 every January 15^th for consulting services occurring during the period commencing January 1^st and ending March 31^st.   BTMB will invoice $25,000 every April 15th for consulting services commencing April 1^st and ending June 30^th.   BTMB will invoice $25,000 every July 15^th for consulting services commencing July 1^st and ending September 30^th.   BTMB will invoice $25,000 every October 15^th for consulting services commencing October 1^st and ending December 31^st.

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This Amendment #2 is executed by individuals who are duly authorized to legally bind their respective parties as of the Amendment #2 Effective Date:

MAGENTA THERAPEUTICS, INC.						NATIONAL MARROW DONOR PROGRAM d/b/a BE THE MATCH BIOTHERAPIES
By:		/s/ ▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇				By:		/s/ ▇▇▇▇ ▇▇▇▇
		Authorized signature						Authorized signature
		▇▇▇▇▇▇▇▇▇ ▇▇▇▇▇▇▇						▇▇▇▇ ▇▇▇▇
		(Typed/Printed Name)						(Typed/Printed Name)
Title:		Chief Business Officer				Title:		Contracts & Procurement Department
Date:		November 13, 2019				Date:		11/12/19

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