The Food and Drug Administration has expanded the indication for pembrolizumab (Keytruda, Merck) to include the use of the targeted immunotherapy agent plus chemotherapy followed by single-agent pembrolizumab in adults with primary advanced or recurrent endometrial cancer.
Approval in this setting was granted following priority review and was based on efficacy demonstrated in the randomized, placebo-controlled, phase 3 KEYNOTE-868/NRG-GY018 trial. The multicenter trial showed improved progression-free survival (PFS) with chemotherapy plus pembrolizumab versus chemotherapy plus placebo in patients with stage 3 or 4 disease or stage IVB recurrent disease in two cohorts: 222 patients with mismatch repair (MMR) deficiency, and 588 patients with MMR proficiency.
Among the MMR-deficient patients, median PFS was not reached in the treatment arm and was 6.5 months in the control arm (hazard ratio, 0.30). Among the MMR-proficient patients, the median PFS was 11.1 versus 8.5 months in the study arms, respectively (HR, 0.60), according to an FDA press release.
Patients in both cohorts were randomized 1:1 to receive 200 mg of either pembrolizumab or placebo every 3 weeks, followed by paclitaxel at a dose of 175 mg/m2 and carboplatin at a dose of AUC 5 mg/mL/min for six cycles and then 400 mg of pembrolizumab or placebo every 6 weeks for up to 14 cycles.
“Adverse reactions associated with pembrolizumab and chemotherapy were generally similar to those previously reported for pembrolizumab or chemotherapy with the exception of a higher incidence of rash,” the FDA noted.
According to the full prescribing information for pembrolizumab, the recommended dose is 200 mg every 3 weeks or 400 mg every 6 weeks until disease progression, unacceptable toxicity, or for up to 24 months.
A version of this article first appeared on Medscape.com.