March 8, 2017

Proposed Merger Will Create Clinical-Stage, Biopharmaceutical Company Focused on the Development and Commercialization of Cytisine for Smoking Cessation

Multiple Clinical and Regulatory Milestones Expected in the Next 12-18 Months

BOTHELL, Wash. and VANCOUVER, British Columbia and MILL VALLEY, Calif., Jan. 5, 2017 /CNW/ –OncoGenex Pharmaceuticals, Inc. (NASDAQ: OGXI) (“OncoGenex”), a publicly held oncology biopharmaceutical company, and Achieve Life Science, Inc. (“Achieve”), a privately held specialty pharmaceutical company, announced today that they have entered into a definitive merger agreement under which OncoGenex will acquire Achieve in an all-stock transaction.

Upon completion of the proposed merger, Achieve’s equity holders are expected to own 75% of the combined company’s outstanding shares and current stockholders of OncoGenex are expected to own the remaining 25% of the combined company’s outstanding shares. Following completion of the merger, OncoGenex Pharmaceuticals, Inc. will be renamed Achieve Life Sciences, Inc.

In addition, prior to the completion of the proposed merger, OncoGenex is expected to distribute to its stockholders contingent value rights (CVRs) for 80% of any net proceeds of certain payments arising from a future sale, transfer, license or similar transaction involving OncoGenex’s apatorsen oncology product candidate.

The combined company’s executive management team will be led by Rick Stewart, Chairman of Achieve; Anthony Clarke, Chief Scientific Officer of Achieve; John Bencich, Chief Financial Officer of OncoGenex; and Cindy Jacobs, Chief Medical Officer of OncoGenex. The combined company plans to utilize select clinical and corporate resources from OncoGenex’s existing operations to accelerate the clinical development program of cytisine for smoking cessation. The board of directors of the combined company is expected to consist of seven members, four of which will be designated by Achieve and three of which will be designated