Reviva Pharmaceuticals (RVPH) SC 13G REVIVA PHARMACEUTICALS / TANG CAPITAL PARTNERS ownership change

Exhibit 99.1

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, the undersigned agree to the joint filing of a Statement on Schedule 13G (including any and all amendments thereto) with respect to the Common Stock, $0.0001 par value per share, of Reviva Pharmaceuticals Holdings, Inc. and further agree to the filing of this Joint Filing Agreement as an exhibit thereto. In addition, each party to this Joint Filing Agreement expressly authorizes each other party to this Joint Filing Agreement to file on its behalf any and all amendments to such Statement on Schedule 13G.

Date: June 3, 2021	TANG CAPITAL PARTNERS, LP
	By:	Tang Capital Management, LLC
	Its:	General Partner
	By:	/s/ Kevin Tang
		Name:	Kevin Tang
		Title:	Manager
	TANG CAPITAL MANAGEMENT, LLC
	By:	/s/ Kevin Tang
		Name:	Kevin Tang
		Title:	Manager
	/s/ Kevin Tang
	Name:	Kevin Tang