Merck KGAa and Pfizer initiate Phase III trials for avelumab to treat gastric/gastro-esophageal junction (GEJ) cancers.

Merck KGaA, Darmstadt, Germany, and Pfizer announced the initiation of two Phase III studies of avelumab,(MSB 0010718C), an investigational, fully human anti-PD-L1 IgG1 monoclonal antibody, in treating advanced or metastatic gastric/gastro-esophageal junction (GEJ) cancers, which are aggressive cancers with poor survival rates. These pivotal trials are investigating avelumab in the first-line and third-line settings, with overall survival (OS) as the primary endpoint in both trials.

JAVELIN Gastric 100 , a study comparing the switch from first-line chemotherapy to maintenance therapy with avelumab versus continuation of chemotherapy, is a multicenter, international, randomized, open-label Phase III trial designed to evaluate the potential superiority (based on OS) of maintenance therapy with avelumab in patients with unresectable, locally advanced or metastatic gastric/GEJ cancers whose disease has not progressed with first-line platinum-based chemotherapy. This is currently the only Phase III trial in gastric cancer that is designed to evaluate superiority of an immunotherapy compared with conventional platinum-based chemotherapy as a first-line maintenance treatment. The study will enroll 629 patients across more than 220 sites in Asia Pacific, Europe, North America and South America.

The third-line study, JAVELIN Gastric 300, is a multicenter, international, randomized, open-label Phase III trial designed to evaluate the potential superiority (based on OS) of avelumab in patients with unresectable, recurrent or metastatic gastric/GEJ cancers, compared with investigator’s choice of chemotherapy from a pre-specified list of therapeutic options. The study will enroll approximately 330 patients, spanning approximately 170 sites in Asia, Australia, Europe, North America and South America.