OPERA: a phase II trial of oregovomab plus non-platinum chemotherapy in PARP inhibitor/platinum-resistant ovarian cancer

A consensus regarding subsequent therapeutic strategies for patients with platinum- and poly (ADP-ribose) polymerase inhibitor (PARPi)-resistant ovarian cancer is lacking. These patients typically receive non-platinum-based chemotherapy; however, survival outcomes remain poor. Compared with chemotherapy alone, combination therapy with novel target agents can provide additional benefits to these patients. Oregovomab, an investigational murine monoclonal antibody against CA-125, has shown promising efficacy in a phase II study in patients with recurrent ovarian cancer. Herein, we described the rationale and design of OPERA/KGOG 3065/APGOT-OV6, a multicenter, investigator-initiated, two-cohort, single-arm phase II trial, aimed at examining the efficacy of oregovomab plus non-platinum-based chemotherapy in patients with PARPi/platinum-resistant ovarian cancer. The primary end point was the objective response rate, according to RECIST 1.1.