Exhibit 99.1
Joint Filing Agreement
The undersigned hereby agree that the Statement on Schedule 13G, Amendment No. 1, dated December 4, 2015 with respect to the shares of Common Stock of CTI Biopharma Corp., 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: December 4, 2015
| 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 adviser | |
| 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. | MSI BVF SPV, LLC | |||
| By: | BVF Partners L.P., its general partner | By: | BVF Partners L.P., its investment adviser | |
| 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 | |||
| BVF INC. | ||||
| BVF PARTNERS L.P. | 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 | |||
| BVF PARTNERS OS LTD. | ||
| By: | BVF Partners L.P., its sole member | |
| By: | BVF Inc., its general partner | |
| By: | /s/ Mark N. Lampert | |
| Mark N. Lampert | ||
| President | ||
| BIOTECHNOLOGY VALUE TRADING FUND OS LP | ||
| By: | BVF Partners L.P., its investment manager | |
| By: | BVF Inc., its general partner | |
| By: | /s/ Mark N. Lampert | |
| Mark N. Lampert | ||
| President | ||