Endometrial cancer: NRG GY018

Professor Toon Van Gorp, an oncological gynaecologist from the University of Leuven, Belgium, discusses the latest findings from the NRG GY018 trial, which were presented at the 2024 SGO conference in San Diego.

This study focused on two distinct patient populations in endometrial cancer: those with MMR-deficient tumours and those with MMR-proficient tumours. A total of 588 MMR-proficient patients and 222 MMR-deficient patients were enrolled in the trial. All patients received identical treatment protocols, with separate analyses conducted for each group.

Patients were randomly assigned in a 1:1 ratio to receive chemotherapy alone or in combination with pembrolizumab, followed by pembrolizumab maintenance therapy every 6 weeks for 2 years. The primary endpoint of the study was PFS in both populations, with OS as a key secondary endpoint, which was presented at the SGO2024 conference.

Final results were pending, as the data maturity was 18% for MMR-deficient patients and 27% for MMR-proficient patients. Nevertheless, a notable trend towards improved OS was observed with pembrolizumab, although statistical significance was not yet achieved at this stage.

The secondary endpoint examined PFS based on the CPS score determined by PD-L1 staining, aiming to elucidate whether differences in PFS existed based on PD-L1 staining. CPS score has demonstrated predictive value for treatment outcomes in various tumours, such as cervical cancer. However, the data presented here revealed no correlation between CPS score and HR in either the MMR-deficient or MMR-proficient populations.

In conclusion, the addition of pembrolizumab treatment to chemotherapy in the first line demonstrated efficacy in both MMR-proficient and MMR-deficient populations, irrespective of CPS score. Although data regarding OS benefits are still maturing, the observed trend is promising.