ESTRO 2025 - Abstract Book

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Invited Speaker

ESTRO 2025

Results: Of 1060 randomized participants (pembrolizumab plus CCRT, n=529; placebo plus CCRT, n=531), 43% of participants had stage IB2 ‒ IIB with node-positive disease and 57% had stage III-IVA at screening. At IA2, median time from randomization to data cutoff (January 8, 2024) was 29.9 months. HRs (95% CIs) were 0.85 (0.62 ‒ 1.16) for PFS and 0.89 (0.55 ‒ 1.44) for OS in participants with stage IB2 ‒ IIB with node-positive disease and 0.57 (0.43 ‒ 0.76) and 0.57 (0.39 ‒ 0.83), respectively, in participants with stage III ‒ IVA disease. Of 1057 participants who completed RT (EBRT plus brachytherapy), median overall treatment time was 52 days in both treatment groups with 74% of participants completing RT within 56 days. Median (IQR) HR-CTV D90% EQD2 doses were 87.2 (82.7 ‒ 91.7) Gy for pembrolizumab plus CCRT and 87.1 (83.4 ‒ 91.6) Gy for placebo plus CCRT. Of 1058 participants in the safety analysis, AE rates were generally balanced between the treatment groups and consistent with known profiles of the individual therapies with no new safety signals after longer follow-up ( Table ). AEs were more common during the pembrolizumab plus CCRT combination therapy phase versus the pembrolizumab monotherapy phase. Hypothyroidism was most common immune-mediated AE with pembrolizumab plus CCRT. Conclusion: Data from the ENGOT-cx11/GOG-3047/KEYNOTE-A18 study support pembrolizumab plus CCRT as the new standard of care for this population, and as an appropriate control arm in future clinical trials.

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Speaker Abstracts How far have we got in the probabilistic approach? Ali Ajdari