Cadonilimab combined with chemotherapy demonstrated robust efficacy and a favorable safety profile in advanced or recurrent endometrial cancer.
Cadonilimab in combination with chemotherapy demonstrated substantial antitumor activity and a manageable safety profile as a first-line treatment for patients with advanced or recurrent endometrial cancer, according to results from the phase 2 CARE trial (NCT06066216) presented at the
Among 41 evaluable patients, the regimen achieved an objective response rate (ORR) of 78.0% (95% CI, 63.3%-88.0%), including 1 complete response (CR) and 31 partial responses (PRs). These findings reflect a high rate of tumor reduction, with the majority of patients experiencing measurable clinical benefit. Stable disease (SD) was observed in 8 patients, resulting in a disease control rate (DCR) of 97.6%, indicating that nearly all treated patients achieved at least disease stabilization.
“Immunotherapy has changed this dilemma,” lead study author Yang Sun, MD, of Fujian Cancer Hospital, said during the presentation, referencing the evolving role of checkpoint inhibition in the frontline setting.
The CARE trial is an investigator-initiated, multicenter, single-arm phase 2 study evaluating cadonilimab in combination with paclitaxel and carboplatin as first-line therapy for advanced or recurrent endometrial cancer. The study incorporated a Simon two-stage design, allowing for expansion based on early response rates observed during the initial stage of enrollment.
Patients received cadonilimab plus chemotherapy every 3 weeks for 6 to 8 cycles. Those achieving CR, PR, or SD transitioned to maintenance cadonilimab for up to 2 years or until disease progression or unacceptable toxicity. The primary end point was ORR, with secondary end points including DCR, progression-free survival (PFS), overall survival (OS), and safety.
A total of 45 patients were treated, with 41 evaluable for efficacy and all included in the safety population. The median follow-up duration was 10.9 months, and the data cutoff occurred on February 28, 2026.
The study population included both newly diagnosed and recurrent cases, with 46.7% newly diagnosed and 53.3% recurrent disease. Endometrioid histology was the most common subtype (66.7%), followed by serous and other histologies. The majority of patients (80%) had pMMR tumors, representing a population with an unmet need for improved immunotherapy strategies. The median age was 60 years (range, 49-75).
In the full analysis set of 45 patients, which included all treated patients regardless of evaluability, the ORR remained high at 71.1%, supporting the consistency of the efficacy signal across the broader study population.
Notably, only 1 patient experienced progressive disease as a best response, underscoring the low rate of primary resistance. Waterfall and swimmer plot analyses presented during the study further illustrated tumor shrinkage in most patients and durable responses in a substantial proportion, with several patients remaining on therapy for extended durations.
The depth of response translated into clinically meaningful durability outcomes. The median PFS was 17.77 months, with a 12-month PFS rate of 58.6%. Although OS data remain immature, the 12-month OS rate reached 88.1%, and the median OS had not yet been reached at the time of data cutoff, suggesting sustained clinical benefit in this patient population.
Subgroup analyses demonstrated consistent efficacy across mismatch repair subtypes. The median PFS was 17.77 months among patients with pMMR tumors and was not reached among those with dMMR disease. The median OS was not reached in either subgroup, indicating that the combination may provide benefit regardless of biomarker status.
The combination of cadonilimab and chemotherapy demonstrated a manageable and predictable safety profile, with no unexpected safety signals observed. Grade 3 or 4 treatment-related adverse events occurred in 17.8% of patients, and no grade 5 events were reported.
The most commonly reported grade 3 to 4 adverse events included rash (4.4%), allergy (4.4%), adrenal insufficiency (2.2%), hyperglycemia (2.2%), myelosuppression (2.2%) and hypokalemia (2.2%). These toxicities are consistent with known immune-related adverse events and chemotherapy-associated effects and were considered manageable with standard supportive care measures.
“These adverse events were manageable,” Sun noted during the presentation, emphasizing the acceptable tolerability of the regimen in the frontline setting.
Disclosures: Sun reported no financial disclosures.
Sun Y, et al. Efficacy and Safety of Cadonilimab Combined With Chemotherapy as the First-line Treatment for Advanced/Recurrent Endometrial Cancer (CARE Trial). Presented at: 2026 Society of Gynecologic Oncology Annual Meeting; April 10-13, 2026; San Juan, Puerto Rico.
