OncoGenex Says FDA Agrees With Phase 3 AFFINITY Protocol Amendment

(RTTNews) - OncoGenex Pharmaceuticals, Inc. (OGXI) said the U.S. Food and Drug Administration has agreed to the company's proposed amendment to the Phase 3 AFFINITY protocol and statistical analysis plan.

The amendment includes the addition of a co-primary endpoint designed to prospectively evaluate the survival benefit of custirsen in men who are at increased risk for poor outcomes when treated with cabazitaxel for metastatic castrate-resistant prostate cancer or CRPC.

The FDA is in agreement with plans for prospectively defining a poor prognostic subpopulation in the Phase 3 AFFINITY trial.

OncoGenex, in collaboration with study investigators, has defined a simple 5-criteria characterization for poor prognosis in prostate cancer based on the Phase 3 SYNERGY trial.

The proposed change for AFFINITY is also consistent with custirsen's mechanism of action, since custirsen was designed to address treatment resistance which may be more prevalent in this subpopulation.

Timing for the final analysis of the poor prognosis subpopulation is expected to occur by the end of this year. The final analysis for the ITT population is projected to occur in the second half of 2016.

OncoGenex has also initiated a review with the European Medicines Agency for the proposed amendment to the Phase 3 AFFINITY protocol and statistical analysis plan. This is expected to be completed in the second half of 2015.