Singapore: Global pharmaceutical company, Pfizer, and Japanese firm, Kyowa Hakko Kirin, are jointly assessing the therapeutic potential of the combination of Pfizer's PF-05082566, an investigational, fully humanized monoclonal antibody (mAb) with Kyowa Hakko Kirin's anti-CCR4 antibody mogamulizumab in a Phase Ib clinical study evaluating the safety and tolerability of the combination in patients with solid tumors.

Pfizer's monoclonal antibody PF-05082566 stimulates signaling through 4-1BB (CD-137), a protein involved in regulation of immune cell activation, proliferation and survival and Kyowa Hakko Kirin's anti-CCR4 antibody mogamulizumab suppresses some of the immune cells that shield the tumor from the immune system.

Under the terms of the agreement, Pfizer and Kyowa Hakko Kirin will co-fund the clinical study, which will be conducted by Pfizer. This study is expected to establish a recommended dose regimen and assess the safety and preliminary efficacy of the combination. This study is expected to begin in 2015 and the results will determine the future clinical development of the combination.

"We believe that combination therapy in immuno-oncology holds great promise to improve outcomes for patients with cancer and provides an exciting opportunity for Pfizer to maximize the potential of our emerging immuno-oncology portfolio," said Dr Mace Rothenberg, senior vice president of Clinical Development and Medical Affairs and chief medical officer for Pfizer Oncology. "Our collaboration with Kyowa Hakko Kirin provides an additional important partnership opportunity to explore the potential of 4-1BB as part of a novel immunotherapy combination regimen."

"With recent progress in the field of cancer immunotherapy, the combination therapy of mogamulizumab and Pfizer's 4-1BB agonist has the potential to bring significant benefits to patients," said Mr Yoichi Sato, managing executive officer, vice president, Head of Research and Development Division of Kyowa Hakko Kirin. "Collaborating with Pfizer, a world's leading pharmaceutical company, on a clinical study in emerging immuno-oncology field is an important component of Kyowa Hakko Kirin's ongoing transformation into a global specialty pharmaceutical company. We are excited about this opportunity."