JOINT FILING AGREEMENT
In accordance with Rule 13d-1(k)(1)(iii) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a Statement on Schedule 13D dated March 15, 2019 (including amendments thereto) with respect to the shares of Common Stock $0.001 par value, of OncoMed Pharmaceuticals, Inc. This Joint Filing Agreement shall be filed as an Exhibit to such Statement.
Dated: March 15, 2019
| BIOTECHNOLOGY VALUE FUND, L.P. | BVF INC. | |||
| By: | BVF Partners L.P., its general partner | By: | /s/ Mark N. Lampert | |
| By: | BVF Inc., its general partner | Mark N. Lampert | ||
| President | ||||
| By: | /s/ Mark N. Lampert | |||
| Mark N. Lampert | ||||
| President | /s/ Mark N. Lampert | |||
| MARK N. LAMPERT | ||||
| BIOTECHNOLOGY VALUE FUND II, L.P. | ||||
| By: | BVF Partners L.P., its general partner | |||
| By: | BVF Inc., its general partner | |||
| By: | /s/ Mark N. Lampert | |||
| Mark N. Lampert | ||||
| President | ||||
| BVF PARTNERS L.P. | ||||
| By: | BVF Inc., its general partner | |||
| By: | /s/ Mark N. Lampert | |||
| Mark N. Lampert | ||||
| President | ||||
| 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 | ||||
