Satsuma Pharmaceuticals (STSA) SC 13G/A Satsuma Pharmaceuticals / Osage University Partners III ownership change

Exhibit 1

AGREEMENT REGARDING JOINT FILING OF SCHEDULE 13G

Pursuant to Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, the undersigned hereby agree that only one statement containing the information required by Schedule 13G need be filed with respect to the ownership by each of the undersigned of securities of the Issuer.

Date: December 4, 2020

OSAGE UNIVERSITY PARTNERS III, LP

By:	OSAGE UNIVERSITY GP III, LLC
	Its General Partner
	By:	/s/ Robert S. Adelson
		Robert S. Adelson, Managing Member
OSAGE UNIVERSITY GP III, LLC
By:	/s/ Robert S. Adelson
	Robert S. Adelson, Managing Member
/s/ William T. Harrington
William T. Harrington
/s/ Marc A. Singer
Marc A. Singer
/s/ Robert S. Adelson
Robert S. Adelson