Exhibit 10.5

Certain identified information has been marked in the exhibit because it is both
(i) not material

and (ii) would likely cause competitive harm to the Company, if publicly
disclosed.

Double asterisks denote omissions.

THIRD AMENDMENT

This Third Amendment, effective as of the date set forth above the signatures of
the parties below (the “Third Amendment Effective Date”), amends the Exclusive
Patent License Agreement having an effective date of November 1, 2013, for
M.I.T. Case No. [**] (the “Agreement”) between the Massachusetts Institute of
Technology (“M.I.T.”), a Massachusetts corporation having its principal office
at 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, USA and Translate
Bio Inc. (formerly, RaNA Therapeutics, Inc.) (“COMPANY”), a Delaware corporation
having a principal place of business at 29 Hartwell Ave., Lexington, MA 02421.
Capitalized terms used herein and not defined shall have the meanings set forth
in the Agreement.

WHEREAS RaNA Therapeutics, Inc., changed its name to Translate Bio, Inc. on
June 26, 2017; and

WHEREAS, COMPANY desires to modify the diligence provisions of the Agreement
consistent with its ongoing work; and

NOW, THEREFORE, in consideration of the promises and mutual covenants contained
herein, the parties hereby agree as follows:

1. Section 3.1, Diligence Requirements, of the Agreement is hereby amended to
delete Sections 3.l(d) and 3.l(e) in their entirety and to replace them with the
following:

(d) First LICENSED PRODUCT.

(1) [**], COMPANY shall [**]

(2) [**], COMPANY shall [**].

(3) [**], COMP ANY shall [**].

(4) [**], COMPANY shall [**].

(5) [**], COMPANY shall [**].

(6) [**], COMPANY shall [**].

--------------------------------------------------------------------------------

(e) Second LICENSED PRODUCT.

(1) [**], COMPANY shall [**].

(2) [**], COMPANY shall [**].

(3) [**], COMP ANY shell [**].

(4) [**], COMPANY shall [**].

(5) [**], COMPANY shall [**].

2. The parties acknowledge that COMPANY has fulfilled the diligence obligations
set forth in Section 3.1(d)(1) and 3.1(d)(2).

3. Except as specifically amended hereby, all other terms of the Agreement are
hereby ratified and shall continue in full force and effect. The Agreement
shall, together with this Third Amendment, be read and construed as a single
instrument.

IN WITNESS WHEREOF, the parties have caused this Third Amendment to be executed
under seal by their duly authorized representatives.

The Effective Date of this Third Amendment is December 31, 2019.

 

Massachusetts Institute of Technology     Translate Bio, Inc.

By:   /s/ Leslie Millar-Nicholson     By:   /s/ Randall Morin Name: Leslie
Millar-Nicholson     Name: Randall Morin Title: Director, TLO     Title:   Vice
President, Head of IP

 

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