Adjuvant Pembrolizumab Significantly Improved DMFS Vs Placebo in Resected Stage IIB/C Melanoma

The phase KEYNOTE-716 trial, which assessed the use of adjuvant pembrolizumab in patients with resected stage IIB and IIC melanoma, met its secondary end point of distant metastasis-free survival.

Treatment with adjuvant pembrolizumab (Keytruda) resulted in a statistically significant improvement in distant metastasis-free survival (DMFS) vs placebo in patients with resected stage IIB to IIC melanoma, according to a press release from Merck on the phase 3 KEYNOTE-716 trial (NCT03553836).1

In addition to data regarding the trial’s secondary end point of DMFS, the interim analysis showed a continued improvement in the primary end point of recurrence-free survival (RFS) vs placebo.

“Patients with melanoma that has spread to distant sites have a significantly worse prognosis and the goal of adjuvant therapy is to delay disease recurrence, especially distant metastases,” Scot Ebbinghaus, MD, vice president of clinical research at Merck Research Laboratories, said in the press release. “In KEYNOTE-716, adjuvant treatment with KEYTRUDA first showed a significant improvement in recurrence-free survival and has now demonstrated a significant improvement in the time until the first diagnosis of a distant metastasis compared [with] placebo. The [DMFS] data from KEYNOTE-716 reinforce the evidence for [pembrolizumab] as adjuvant therapy in stage IIB and IIC melanoma.”

In the study, adult patients were treated with 200 mg of pembrolizumab, and pediatric patients received 2 mg/kg every 3 weeks for 17 cycles. To be eligible for the trial, patients were required to be 12 years or older with newly diagnosed disease and have undergone surgical resection. Patients were also required to have an ECOG performance status of 0 or 1. A total of 976 patients were randomized to receive either pembrolizumab (n = 487) or placebo (n = 489).

Findings from the trial that were previously reported at the 2021 European Society for Medical Oncology Congress highlighted a significant improvement in outcomes with pembrolizumab vs placebo, indicating a median RFS that was not reached in either cohorts (HR, 0.65; 95% CI, 0.46-0.92; P = .00658).2 The 12-month RFS rates were 90.5% and 83.1% in the pembrolizumab and placebo cohorts, respectively.

Pembrolizumab was approved by the FDA for the treatment of patients with stage IIB/C melanomafor adults and children in December 2021 based on the results of the phase 3 KEYNOTE-716 trial.

References

  1. Merck’s KEYTRUDA® (pembrolizumab) demonstrated significant improvement in distant metastasis-free survival (DMFS) compared to placebo as adjuvant therapy for patients with resected stage IIB and IIC melanoma in phase 3 KEYNOTE-716 trial. News release. Merck. March 7, 2022. Accessed March 7, 2022. https://bit.ly/35W3UFY
  2. Luke JJ, Rutkowski P, Queirolo P, et al. Pembrolizumab versus placebo after complete resection of high-risk stage II melanoma: efficacy and safety results from the KEYNOTE-716 double-blind phase III trial. Ann Oncol. 2021;32(suppl 5):S1283-S1346. doi:10.1016/annonc/annonc741