EXHIBIT A

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on this Schedule 13D, dated May 6, 2019 (the “Schedule 13D”), with respect to the Shares of Novus Therapeutics, Inc. is filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities and Exchange Act of 1934, as amended, and that this Agreement shall be included as an Exhibit to this Schedule 13D.  Each of the undersigned agrees to be responsible for the timely filing of the Schedule 13D, and for the completeness and accuracy of the information concerning itself contained therein.  This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the 6th day of May, 2019.

ORBIMED ISRAEL BIOFUND GP LIMITED PARTNERSHIP
By:	OrbiMed Israel GP Ltd., its General Partner
By:	/s/ Nissim Darvish
	Nissim Darvish
	Director
ORBIMED ISRAEL GP LTD.
By:	/s/ Nissim Darvish
	Nissim Darvish
	Director