FDA Expands Approval of Treatment Combination for Endometrial Cancer

This month, the US Food and Drug Administration (FDA) approved dostarlimab-gxly (Jemperli, GSK) with carboplatin and paclitaxel, followed by single-agent dostarlimab-gxly, for adult patients with primary advanced or recurrent endometrial cancer (EC). Dostarlimab-gxly was previously approved with carboplatin and paclitaxel, followed by single-agent dostarlimab-gxly, for primary advanced or recurrent EC that is mismatch repair deficient or microsatellite instability-high.

Treatment efficacy was assessed in RUBY, a randomized, multicenter, double-blind, placebo-controlled trial comprising 494 patients with primary advanced or recurrent EC. Patients in the population of interest were randomized 1:1 to either dostarlimab-gxly with carboplatin and paclitaxel, followed by dostarlimab-gxly, or placebo with carboplatin and paclitaxel, followed by placebo.

The major efficacy end point measures were progression-free survival (PFS) and overall survival (OS). According to the results, in the overall population, researchers observed a statistically significant OS improvement, with a median OS of 44.6 months (95% CI, 32.6 to not reached) and 28.2 months (95% CI, 22.1-35.6) in the dostarlimab-gxly and placebo arms, respectively (hazard ratio [HR], 0.69 [95% CI, 0.54-0.89]; 1-sided P=.002). The median PFS in the overall population was 11.8 months (95% CI, 9.6-17.1) and 7.9 months (95% CI, 7.6-9.5) in the dostarlimab-gxly and placebo arms, respectively (HR, 0.64 [95% CI, 0.51-0.80]; 1-sided P<.0001).

The recommended dostarlimab-gxly dose is 500 mg every 3 weeks for 6 cycles with carboplatin and paclitaxel, followed by 1000-mg monotherapy every 6 weeks until disease progression or unacceptable toxicity, or up to 3 years. Some of the most common adverse reactions (≥20%) with dostarlimab-gxly with carboplatin and paclitaxel include anemia, increased creatinine, peripheral neuropathy, decreased white blood cell count, fatigue, nausea, alopecia, low platelets, increased glucose, lymphopenia, neutropenia, liver function test abnormalities, arthralgia, rash, constipation, diarrhea, decreased albumin, abdominal pain, and dyspnea.