A Phase 3 Study of Manganese-primed Immunochemotherapy in Patients With Advanced Ovarian Cancer

Epithelial ovarian cancer is the most lethal gynecologic malignancy, and most patients eventually relapse and develop resistance to available therapies. Immune checkpoint inhibitors have shown limited overall efficacy in recurrent ovarian cancer, partly because of its immunosuppressive tumor microenvironment. Manganese (Mn2+) can activate the cGAS-STING pathway and may enhance antitumor immunity and the therapeutic effects of PD-1 blockade combined with chemotherapy. Following encouraging findings from an early-phase study, a randomized, single-blind, placebo-controlled phase II trial showed that the addition of manganese chloride to anti-PD-1 antibody, nab-paclitaxel, and cisplatin improved clinical outcomes compared with placebo, with an overall manageable safety profile. Based on these findings, this phase III trial is designed to confirm the efficacy and further evaluate the safety of Mn2+-primed immunochemotherapy in patients with advanced ovarian cancer.