Threshold Pharmaceuticals Announces Positive Phase 2b Clinical Trial Results of TH-302 in Patients With Pancreatic Cancer

Threshold Pharmaceuticals, Inc.

today announced that its 214 patient randomized controlled Phase 2b clinical trial evaluating the efficacy and safety of two doses of the investigational agent TH-302 in combination with gemcitabine compared to gemcitabine alone in patients with first-line advanced pancreatic cancer achieved its primary endpoint, with a 63% improvement in progression free survival and a safety profile consistent with previous studies. "With the results of this trial, we are again very encouraged that TH-302 is conferring benefit to patients with aggressive and difficult to treat cancers," said Barry Selick, Ph.D., Chief Executive Officer of Threshold. "We look forward to its ongoing development with our partner Merck KGaA in this and other indications." Clinical Trial Design Study TH-CR-404 is a multi-center, randomized, controlled, dose-ranging, Phase 2b crossover clinical trial of TH-302 in combination with gemcitabine in patients with first line advanced pancreatic cancer. The primary endpoint of the trial is progression-free survival. The secondary endpoints are overall response rate, overall survival, change in CA19-9 as well as various other efficacy and safety parameters. Tumor response was evaluated at baseline and every eight weeks using RECIST. Patients for whom monotherapy with gemcitabine is considered standard therapy were eligible for the trial. Patients were randomized equally into one of three cohorts: TH-302 at a dose of 240 mg/m2 plus gemcitabine, TH-302 at a dose of 340 mg/m2 plus gemcitabine, or gemcitabine alone. Patients who successfully completed six cycles of treatment without evidence of significant treatment-related toxicity or progressive disease could continue to receive treatment. If a patient experienced cancer progression on gemcitabine alone, the patient could cross over into one of the TH-302 plus gemcitabine cohorts. The primary efficacy analysis was performed based upon 149 investigator-assessed PFS events and, per protocol, pooled data from the two gemcitabine plus TH-302 dose groups in comparison to gemcitabine alone.