132P - An open-label, prospective phase II study of cadonilimab in combination with neoadjuvant chemotherapy for patients diagnosed with advanced ovarian cancer (AK104-IIT-003)

Background

There is an unmet need to improve neoadjuvant chemotherapy (NAC) to decrease postoperative residual disease (R0 rate: 50%) and improve prognosis in ovarian cancer (OC). R0 rate and histopathological response of interval cytoreductive surgery (IDS) after NAC combined with immune checkpoint inhibitors were reported to be encouraging. Cadonilimab (AK104) is a tetravalent bispecific antibody targeting PD-1 and CTLA-4. In this study, we report the efficacy and safety of AK104 with NAC in patients with advanced-stage ovarian cancer (NCT05430906).

Methods

This study is an open-label, prospective, single arm, phase II study of evaluating the efficacy and safety of cadonilimab combined with chemotherapy as neoadjuvant treatment for advanced ovarian cancer. Patients received neoadjuvant therapy of cadonilimab plus platinum-taxane chemotherapy (3 to 4 cycles) followed by surgery. The primary endpoint was the R0 rate. The secondary endpoints included objective response rate (ORR), disease control rate (DCR), chemotherapy response score (CRS), pathologic complete response (pCR), progression-free survival (PFS), and safety.

Results

28 patients were enrolled from Dec 12, 2022, to Sep 12, 2024. The median patient age was 54 years (range 45–70 years), and most patients presented with high-grade serous carcinoma (96.4%) and FIGO stage IVa(14.3%), IVb disease (67.9%). 23 (82.1%) patients had undergone IDS with an R0 resection rate of 78.3%. ORR was 92.3%, including 7.7% CR and 84.6% PR. 21.7% achieved pCR, and 13.0% had a CRS of 3. The median PFS was 17.3 months. Overall survival data remained immature as of the cut-off date. Treatment-related AEs (TRAEs) of any grade occurred in 15 (53.6%) patients. Grade ≥3 TRAEs occurred in 3 (10.7%) patients. Grade ≥ 3 irAE (immune⁃mediated colitis) occurred in 1 (3.6%) patient. All of the TRAEs, including severe AEs, were manageable, with no new safety concerns in this study.

Conclusions

This study showed promising activity with a durable clinical response, supporting the potential of NAC with cadonilimab in advanced-stage ovarian cancer. Meanwhile, long-term overall survival data require ongoing assessment.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.