Leap Therapeutics has entered into a collaboration agreement with Merck KGaA, Darmstadt, Germany, and Pfizer to evaluate Leap’s GITR agonist, TRX518, in combination with avelumab*, a human anti-PD-L1 IgG1 monoclonal antibody, and chemotherapy.

Under the terms of the collaboration, Leap will be conducting a Phase I/II clinical trial in advanced solid tumors including expansion populations in patients with relapsed/refractory ovarian, breast, and prostate cancers. The study is expected to begin enrolling patients in the first quarter of 2019.

“The combination of TRX518 with anti-PD-L1 immunotherapy and cyclophosphamide has a solid scientific rationale and we look to build upon our early clinical and preclinical data highlighting the potential benefits of such a combination,” said Cynthia Sirard, M.D., vice president, Clinical Development of Leap Therapeutics.

“TRX518 has demonstrated encouraging potential with early clinical activity in patients with advanced solid tumors,” said Chris Boshoff, M.D., Ph.D., senior vice president and head of Immuno-oncology, Early Development and Translational Oncology, Pfizer Global Product Development. “This collaboration with Leap Therapeutics to evaluate TRX518 in combination with avelumab gives us the opportunity to investigate a potential novel immunotherapy treatment regimen as we pursue our mission of improving outcomes for patients living with hard-to-treat cancers.”

“Combination therapy remains a major focus in our clinical development program for avelumab in an effort to advance the treatment landscape for patients with challenging cancers,” said Alise Reicin, head of Global Clinical Development at the Biopharma business of Merck KGaA, Darmstadt, Germany, which in the US and Canada operates as EMD Serono. “Through our collaboration with Leap Therapeutics, we are eager to further understand the potential of this novel immunotherapy combination in this patient population.”

Avelumab has received accelerated approval by the FDA for the treatment of patients with metastatic Merkel cell carcinoma (MCC) and previously treated patients with locally advanced or metastatic urothelial carcinoma (mUC), and is under further clinical evaluation across a range of tumor types under a global strategic alliance between Merck KGaA, Darmstadt, Germany, and Pfizer.