JOINT FILING AGREEMENT The undersigned, MVIL, LLC is jointly filing the attached Initial Statement of Beneficial Ownership on Form 3 with MORNINGSIDE VENTURE INVESTMENTS LIMITED with respect to the beneficial ownership of securities of Amylyx...

                               JOINT FILING AGREEMENT

The undersigned, MVIL, LLC is jointly filing the attached Initial Statement of
Beneficial Ownership on Form 3 with MORNINGSIDE VENTURE INVESTMENTS LIMITED
with respect to the beneficial ownership of securities of Amylyx
Pharmaceuticals, Inc.

For and on behalf of

MVIL, LLC


By: /s/ Xxxxx Xxx Xxxx Xxxxx
    -------------------------
Xxxxx Xxx Xxxx Xxxxx, Manager