Bavarian Nordic initiated a phase II clinical trial of its prostate cancer immunotherapy candidate, PROSTVAC (rilimogene), in combination treatment with YERVOY (ipilimumab) and/or OPDIVO (nivolumab), both of which are immune checkpoint inhibitors from Bristol-Myers Squibb, as neoadjuvant therapy in patients with localized prostate cancer.

A lead-in stage will evaluate the safety of the combination of all three drugs in 10 patients with castration-resistant prostate cancer, followed by enrollment of up to 55 patients with localized prostate cancer in three cohorts, who will receive PROSTVAC in combination with either ipilimumab or nivolumab, or a combination of all three drugs prior to undergoing radical prostatectomy. The primary endpoint of the study is to evaluate and compare changes in T cell infiltration in the tumor after neoadjuvant treatment across the three different cohorts.

The principal investigator of the study is James L. Gulley, MD, Senior Investigator, Center for Cancer Research, part of the National Cancer Institute (NCI), and the sponsor of the study.  

"There are now 11 ongoing studies of PROSTVAC across various stages of prostate cancer. In recent years, there has been a growing interest in the evaluation of the immunotherapy candidate in earlier disease stages, where the cancer has not yet spread beyond the prostate. We are excited to learn more about the potential of PROSTVAC for treating this population, and to evaluate the potential synergistic effects of combining the vaccine with checkpoint inhibitors, as we believe PROSTVAC may enhance the clinical activity of these drugs," said Paul Chaplin, president & chief executive officer of Bavarian Nordic.

This is the second trial conducted in collaboration with Bristol-Myers Squibb. The first trial was initiated in October 2016, and is investigating the combination treatment of PROSTVAC and ipilimumab at the University of California, San Francisco (UCSF), also in a neoadjuvant setting.