Threshold Says Target Enrollment Achieved In Phase 3 Trial Of TH-302

(RTTNews) - Threshold Pharmaceuticals, Inc. (THLD) announced that the target enrollment of 620 patients with advanced soft tissue sarcoma was met in its pivotal Phase 3 trial of TH-302, its investigational hypoxia-targeted drug. This enrollment achievement triggers a milestone payment of $12.5 million from Merck KGaA, Darmstadt, Germany. Threshold has a global license and co-development deal with Merck for TH-302, including an option for Threshold to co-commercialize in the U.S. The company believes that TH-302 would ultimately be shown to be both safe and efficacious in this patient population for which there is an urgent unmet medical need.

TH-302 is an investigational hypoxia-targeted drug that is designed to be activated under tumor hypoxic conditions, a hallmark of many cancers.

The firm is conducting this international, randomized, pivotal Phase 3 study along with the Sarcoma Alliance for Research through Collaboration or SARC. The trial is enrolling patients with metastatic or locally advanced unresectable soft tissue sarcoma and is designed to evaluate the efficacy and safety of TH-302 in combination with doxorubicin, compared to doxorubicin alone.

Although Threshold would remain blinded to its ongoing Phase 3 trial data, an Independent Data Monitoring Committee or IDMC, which monitors patient safety on an ongoing basis, would conduct an interim efficacy and safety analysis after 235 deaths are reported. The timing of the interim analysis, which is event-based and therefore dependent on the length of survival of patients, is now projected to be conducted in mid-2014. Unless the IDMC urges that the study end early, top-line results of the primary efficacy analysis are currently projected to be reported in the first half of 2015.

Sarcomas are a group of aggressive cancers of connective tissues of the body for which there are currently limited treatment options, and soft tissue sarcomas are treated with surgery, chemotherapy and radiation.