Threshold falls on OS data for TH-302

Threshold Pharmaceuticals Inc. (NASDAQ:THLD) fell $1.72 (20%) to $7 on Monday after reporting that TH-302 plus gemcitabine non-significantly improved median overall survival (OS), a secondary endpoint, vs. gemcitabine alone in the Phase IIb TH-CR-404 trial to treat advanced pancreatic cancer. TH-302 plus gemcitabine led to a median OS of 8.7 months in patients receiving 240 mg/m2 (p=0.827) and 9.2 months in patients receiving 340 mg/m2 (p=0.8) vs. 6.9 months in patients receiving gemcitabine alone. Threshold said the trial was not designed to detect a significant improvement in OS. The company added that patients who crossed over from the gemcitabine alone arm to receive gemcitabine plus TH-302 upon disease progression contributed to an increase in survival in the control arm. As such, Threshold said it believes the lack of significant OS data was partly due to the crossover design of the trial. Data will be presented at the European Society for Medical Oncology meeting in Vienna this month. ...