Abstract CT158: ATHENA (GOG-3020/ENGOT-ov45): a randomized, double-blind, placebo-controlled, Phase III study of rucaparib + nivolumab following front-line platinum-based chemotherapy in ovarian cancer

Abstract

Abstract Background: The poly(ADP-ribose) polymerase (PARP) inhibitor rucaparib has demonstrated clinical activity in patients with ovarian cancer with or without homologous recombination (HR) deficiency (HRD; eg, a BRCA mutation or high genome-wide loss of heterozygosity [LOH high]). ATHENA (NCT03522246) is evaluating rucaparib + the anti-PD-1 antibody nivolumab as maintenance treatment following front-line platinum-based chemotherapy in patients with newly diagnosed, high-grade ovarian, fallopian tube, or primary peritoneal cancer. The rationale for evaluating this combination includes the following: tumors with a deleterious BRCAmutation express novel, tumor-specific protein sequences (neoantigens), which can attract PD-L1-expressing, tumor-infiltrating lymphocytes; ovarian tumors with HRD have more neoantigens relative to HR-proficient tumors and may respond preferentially to immune checkpoint inhibitors; and rucaparib combined with anti-PD-1 or anti-PD-L1 demonstrated improved antitumor activity in a syngeneic ovarian cancer BrKras (BRCA1-/-; TP53-/-; MYC; KRAS-G12D; AKT) model. Furthermore, it is hypothesized that DNA damage induced by PARP inhibition may increase neoantigens regardless of HRD status. Methods: Eligible patients must have completed first-line platinum doublet chemotherapy and surgery. Patients had to have achieved an investigator-assessed response without disease progression or rising CA-125 at any time during first-line platinum doublet treatment. Cytoreductive surgery (R0 permitted) could have been completed either prior to chemotherapy (primary surgery) or following neoadjuvant chemotherapy (interval debulking). Patients will be randomized 4:4:1:1 to receive maintenance treatment in Arm A (oral rucaparib 600 mg BID + intravenous [IV] nivolumab 480 mg on day 1 of every 4-week cycle), Arm B (oral rucaparib + IV placebo), Arm C (oral placebo + IV nivolumab), or Arm D (oral placebo + IV placebo). Stratification factors include centrally determined tumor HRD status (BRCA mutant, non-BRCA mutant/LOH high, non-BRCA mutant/LOH low, or non-BRCA mutant/LOH indeterminate), posttreatment disease status (residual vs no residual disease), and timing of surgery (primary vs interval debulking). The primary endpoint of investigator-assessed progression-free survival (per RECIST version 1.1) will be evaluated in 3 independent comparisons between arms: A vs B, A vs D, and B vs D. Secondary endpoints include blinded independent central review of progression-free survival, overall survival, investigator-assessed objective response rate, investigator-assessed duration of response, and safety. Enrollment is ongoing; patients (n≈1000) will be enrolled at >270 sites worldwide. Citation Format: Shannon N. Westin, Rebecca S. Kristeleit, Robert L. Coleman, Keiichi Fujiwara, Amit M. Oza, David M. O’Malley, Thomas J. Herzog, Frederik Marmé, Ana Oaknin, Ramez Eskander, Domenica Lorusso, Tamar Safra, Jacob Korach, Kevin K. Lin, Danny Shih, Lisa Caunt, Sandra Goble, Stephanie Hume, Lara Maloney, Iain McNeish, Bradley J. Monk. ATHENA (GOG-3020/ENGOT-ov45): a randomized, double-blind, placebo-controlled, Phase III study of rucaparib + nivolumab following front-line platinum-based chemotherapy in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT158.