Exhibit 99.1

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on Schedule 13G dated February 3, 2010 with respect to the shares of Common Stock of SuperGen, Inc., and any further amendments thereto executed by each and any of the undersigned shall be filed on behalf of each of the undersigned pursuant to and in accordance with the provisions of Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended.

Dated: February 3, 2010

BIOTECHNOLOGY VALUE FUND, L.P.		INVESTMENT 10, L.L.C.
By:	BVF Partners L.P., its general partner	By:	BVF Partners L.P., its investment manager
By:	BVF Inc., its general partner	By:	BVF Inc., its general partner
By:	/s/ Mark N. Lampert	By:	/s/ Mark N. Lampert
	Mark N. Lampert		Mark N. Lampert
	President		President

BIOTECHNOLOGY VALUE FUND II, L.P.		BVF PARTNERS L.P.
By:	BVF Partners L.P., its general partner	By:	BVF Inc., its general partner
By:	BVF Inc., its general partner	By:	/s/ Mark N. Lampert
			Mark N. Lampert
By:	/s/ Mark N. Lampert		President
	Mark N. Lampert
	President

BVF INVESTMENTS, L.L.C.		BVF INC.
By:	BVF Partners L.P., its manager	By:	/s/ Mark N. Lampert
			Mark N. Lampert
By:	BVF Inc., its general partner		President
By:	/s/ Mark N. Lampert
	Mark N. Lampert	/s/ Mark N. Lampert
	President	MARK N. LAMPERT