FDA Approves Pembrolizumab as Adjuvant Treatment for Adult, Pediatric Patients With Melanoma

Pembrolizumab is the first anti-PD-1/anti-PD-L1 therapy to demonstrate a recurrence-free survival benefit in the adjuvant setting for melanoma.

Officials with the FDA have approved pembrolizumab (Keytruda; Merck) for the adjuvant treatment of adult and pediatric patients with stage IIB or IIC melanoma following complete resection. The indication for pembrolizumab as adjuvant treatment for stage III melanoma was also expanded to include pediatric patients 12 years of age and older.

According to a press release, this marks the first anti-programmed cell death protein-1 (PD-1)/anti-programmed cell death ligand-1 (PD-L1) therapy to demonstrate a recurrence-free survival benefit in the adjuvant setting for this disease. Pembrolizumab is now approved as an adjuvant treatment for patients 12 years of age and older with completely resected melanoma across stage IIB, stage IIC, and stage III disease.

Melanoma is the most serious form of skin cancer and is characterized by the uncontrolled growth of pigment-producing cells. Rates of the disease have increased over recent decades, with nearly 325,000 new cases diagnosed worldwide in 2020.

The recurrent rates for resected melanoma are estimated to be between 32% and 46% for patients with stage IIB and stage IIC disease and between 39% and 74% for patients with stage III disease. The 5-year survival rates are estimated to be 87% for stage IIB, 82% for stage IIC, 93% for stage IIIA, 83% for stage IIIB, 69% for stage IIIC, and 32% for stage IIID.

“The standard of care for patients with resected stage IIB and IIC melanoma has been observation, despite the fact that for these patients, the risk of recurrence is nearly the same as for patients with later-stage disease for whom treatment is recommended,” said Jason Luke, MD, FACP, director of the Cancer Immunotherapeutics Center at the UPMC Hillman Cancer Center, in the press release. “Today’s approval of pembrolizumab for the adjuvant treatment of patients 12 years and older with stage IIB and IIC melanoma following complete resection is an important advance that provides these patients with a new option that can help reduce the risk of their cancer returning.”

The approval is based on data from the first interim analysis of the phase 3 KEYNOTE-716 trial, in which pembrolizumab showed a statistically significant improvement in recurrence-free survival. According to the press release, treatment with pembrolizumab reduced the risk of disease recurrence or death by 35% compared to placebo. Median recurrence-free survival was not reached for either group. After a median follow-up of 14.4 months, 11% of patients who received pembrolizumab had recurrence or died compared to 17% of patients who received placebo.

The KEYNOTE-716 trial is a multicenter, randomized, double-blind, placebo-controlled phase 3 trial that enrolled 976 patients with completely resected stage IIB or IIC melanoma. Patients were randomized to receive pembrolizumab 200 mg, the pediatric dose of 2 mg/kg intravenously, or placebo every 3 weeks for up to 1 year until disease recurrence or unacceptable toxicity.

Furthermore, the efficacy of pembrolizumab in pediatric patients with stage IIB, IIC, and III melanoma is supported by extrapolation of efficacy data from adults, based on similar biology, pharmacology of drug effect, and similar exposure-response for efficacy and safety.

Clinicians should be aware of immune-mediated adverse reactions, which can be severe or fatal and can occur in any organ system or tissue and can affect more than 1 body system simultaneously. Immune-mediated adverse reactions can also occur at any time during or after treatment with pembrolizumab, including pneumonitis, colitis, hepatitis, endocrinopathies, nephritis, dermatologic reactions, solid organ transplant rejection, and complications of allogeneic hematopoietic stem cell transplantation.

“Keytruda was the first anti-PD-1 therapy to be approved in metastatic melanoma in the US 7 years ago. Since then, we have built on this foundation in melanoma and have expanded the use of Keytruda into earlier stage of this disease.” said Scot Ebbinghaus, MD, vice president of clinical research at Merck Research Laboratories, in the press release. “With today’s approval, we can now offer health care providers and patients 12 years and older the opportunity to help prevent melanoma recurrence with Keytruda across resected stage IIB, stage IIC, and stage III melanoma.”

REFERENCE

FDA Approves Merck’s Keytruda (pembrolizumab) as Adjuvant Treatment for Adult and Pediatric Patients With Stage IIB or IIC Melanoma Following Complete Resection. News release. Merck; December 3, 2021. Accessed December 9, 2021. https://www.merck.com/news/fda-approves-mercks-keytruda-pembrolizumab-as-adjuvant-treatment-for-adult-and-pediatric-%e2%89%a512-years-of-age-patients-with-stage-iib-or-iic-melanoma-following-complete-resectio/