Cadonilimab Delivers 100% 24-Month Survival Rate in Complete Responders With R/M Cervical Cancer

The latest long-term survival analysis from the COMPASSION-03/AK104-201 phase 2 study (NCT03852251)¹ demonstrates that cadonilimab, a first-in-class PD-1/CTLA-4 bispecific antibody, provides profound and durable clinical benefits for patients with recurrent or metastatic cervical cancer who have failed prior platinum-containing chemotherapy.²

Key findings from the 26.5-month median follow-up include a landmark 100% 24-month overall survival (OS) rate among patients who achieved a complete response (CR). Furthermore, cadonilimab demonstrated sustained efficacy regardless of PD-L1 expression status, addressing a critical unmet need for patients with PD-L1 negative or "cold" tumors. These results solidify cadonilimab's role as a foundational immunotherapy backbone, offering superior efficacy and a manageable toxicity profile compared with traditional PD-1/L1 or CTLA-4 monotherapies.

The data revealed a strong positive correlation between response depth and survival duration.

Patients achieving complete response (CR) showed the most significant survival benefits, with a 24-month OS rate of 100%. The median OS was not achieved (NA). The 12-month progression-free survival (PFS) rate was 84.6%, and the median PFS was NA, as well as the median duration of response.

Patients achieving partial response also experienced substantial, though comparatively lower, survival benefits, achieving a 24-month OS rate of 63%. The median OS was NA. The 12-month PFS rate was 47.3%, and the median PFS was 11.17 months.

In the total patient population, the median OS was 17.5 months. Long-term follow-up (median 26.5 months) demonstrated sustained survival, with OS rates of 47.8% at 18 months and 40.9% at 24 months. Notably, cadonilimab demonstrated clinical utility regardless of PD-L1 expression, benefiting both PD-L1–positive and PD-L1–negative (CPS < 1) patients.

The updated survival analysis from the COMPASSION-03 trial involved 99 efficacy-evaluable patients. Investigators sought to determine if a deeper best overall response (BOR) to cadonilimab monotherapy correlated with superior long-term survival in the recurrent/metastatic setting.

COMPASSION-03 was a pivotal, registrational phase 2 trial designed to assess cadonilimab as a second-line monotherapy for patients whose cervical cancer progressed following platinum-based regimens.

The study enrolled a challenging population; over 18% were PD-L1–negative, and 36% had undergone 2 or more prior lines of systemic therapy.

As a bispecific antibody, cadonilimab simultaneously blocks PD-1 and CTLA-4. This dual-inhibitory approach is engineered to maximize the synergistic potential of both pathways while mitigating the toxicity often associated with combination checkpoint inhibitors.

Since its 2022 commercial launch, cadonilimab has secured approval in China for first-line gastric cancer, as well as both first-line and recurrent/metastatic cervical cancer. Its broader clinical potential is currently being investigated in 11 different phase 3 registrational trials.

This specific long-term efficacy update did not include new or specific safety data regarding adverse event rates.

The long-term phase 2 results of cadonilimab in recurrent/metastatic cervical cancer confirm its potential to significantly extend life, particularly for patients achieving complete remission. Its ability to perform across all levels of PD-L1 expression and its manageable safety profile positions it as a significant advancement over first-generation immunotherapies.

REFERENCES

1.Cadonilimab achieves 100% 24-month OS in complete responders in R/M cervical cancer based on long-term phase II results. News release. Akeso, Inc. Published March 4, 2026. Accessed March 17, 2026. https://tinyurl.com/y45tehfj

2.A study of AK104, a PD-1/CTLA-4 bispecific antibody, for advanced solid tumors or with mXELOX/XELOX as first-line therapy for advanced gastric or GEJ adenocarcinoma. ClinicalTrials.gov. Updated August 2, 2024. Accessed March 17, 2026. https://clinicaltrials.gov/study/NCT03852251