Background There is mounting pre-clinical and clinical evidence that combinations of immunotherapy, specifically programed cell death-1 (PD-1) inhibition, with chemotherapy and anti-angiogenesis agents, such as bevacizumab, result in markedly improved outcomes across a variety of tumor types including endometrial cancer, renal cell cancer, and non-small cell lung cancer. IMagyn050/GOG 3015/ENGOT-OV39 is the first, randomized, phase III trial to evaluate the potential impact of this combination on both progression-free survival and overall survival in patients presenting with advanced epithelial ovarian cancer.

Primary Objective The primary objective is to evaluate the efficacy of atezolizumab versus placebo in combination with paclitaxel + carboplatin + bevacizumab for front-line treatment of ovarian cancer among all patients and those with PD-L1+ tumors.

Study Hypothesis This study will test the hypothesis that treatment with atezolizumab added to paclitaxel, carboplatin, and bevacizumab will prolong progression-free survival and overall survival compared with treatment with placebo plus paclitaxel, carboplatin, and bevacizumab.

Trial Design This is a randomized, phase III, placebo-controlled study.

Major Inclusion/Exclusion Criteria Eligible patients have a histologic diagnosis of advanced epithelial ovarain cancer, primary peritoneal, or fallopian tube cancer who either have residual disease after primary surgery or who are undergoing neoadjuvant chemotherapy with planned interval surgery. Ineligible patients include those who are cured with surgery alone or those for whom no gross residual disease remained following primary cytoreduction.

Primary Endpoint There are two co-primary efficacy endpoints: investigator-assessed progression-free survival and overall survival.

Sample Size 1300 patients.

Estimated Dates for Completing Accrual and Presenting Results April 2020.

Trial Registration NCT03038100.