Exelixis announces results for cabozantinib phase 1 combination trial
Exelixis announced results from a phase 1 trial of cabozantinib in combination with nivolumab in patients with previously treated genitourinary tumors. The findings will be presented during a poster discussion session on October 9 at the European Society for Medical Oncology 2016 Congress, which is being held in Copenhagen, October 7-11. "The treatment landscape for advanced, intractable cancers such as metastatic urothelial carcinoma is continuously evolving and the use of combination therapies may improve outcomes for patients in need of new options," said Andrea Apolo, M.D., Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, the principal investigator of the trial. "Our previous correlative studies have demonstrated that cabozantinib has immunomodulatory properties that may counteract tumor-induced immunosuppression, providing the rationale for this trial.1,2 These promising early stage clinical findings support further investigation of cabozantinib in combination with nivolumab in a number of genitourinary tumors." Between July 2015 and September 2016, 24 patients were accrued with metastatic urothelial carcinoma, urachal adenocarcinoma, squamous cell carcinoma of the bladder or urethra, germ cell tumor, castration-resistant prostate cancer, renal cell carcinoma, or trophoblastic tumor and were treated in Part I of the study, which evaluated the combination of cabozantinib and nivolumab at four dose levels. The median number of prior systemic therapies was 3, and 10 patients had received 4 or more prior therapies. The objective response rate was 43 percent among the 23 patients who were evaluable for response, with one complete response and nine partial responses. Four of six patients with urothelial cancer achieved a response. The recommended doses for the ongoing expansion cohorts were determined to be cabozantinib at 40 mg daily and nivolumab at 3 mg/kg once every 2 weeks. Part II of the phase 1 trial examining the use of the triplet combination of cabozantinib, nivolumab, and ipilimumab is also ongoing.