The anti–PD-1 immunotherapy pembrolizumab increases long-term survival in some patients with advanced melanoma, according to updated results of KEYNOTE-001.
Among the 655 patients studied in the phase 1b trial, the 3-year overall survival rate for advanced melanoma patients treated with pembrolizumab was 40%, Dr. Caroline Robert reported in a presscast leading up to the annual meeting of the American Society of Clinical Oncology.
Median overall survival was 24.4 months. Before 2011, patients with advanced melanoma had a median overall survival of less than one year, said Dr. Robert, head of the dermatology unit at the Institut Gustave-Roussy in Paris.
Study participants received pembrolizumab at either 2 or 10 mg/kg every 3 weeks. During the trial, 2 mg/kg every 3 weeks was determined to be the optimal dosing regimen. Patients remained on the treatment until disease progression, intolerable toxicity, or investigator decision. Eight percent of patients stopped treatment due to drug-related symptoms, and there were no drug-related deaths.
Survival rates differed slightly based on prior melanoma treatment. Of the 655 patients in the study, 75% had received previous treatments; patients who had not received prior treatment had slightly higher survival at 45%.
Overall response rate was 33%. Responses were durable as 73% of patients had a response rate of two or more years. Ninety-five patients had a complete response, and 61 of those patients stopped treatment following the complete response.
“I really hope for a cure for these people,” Dr. Robert said.
Pembrolizumab was generally well tolerated with the most common adverse events being fatigue (40%), itchiness (28%), and rash (23%).
ASCO spokesperson and moderator, Dr. Don Dizon, said the results of this study are “incredibly exciting given they came from a phase I trial. This is a new treatment and the longest follow-up of people [with melanoma] who have received pembrolizumab.” Dr. Dizon hopes to “potentially see a cure [for] melanoma” given the reported durability and response rate to the drug.
On Twitter @JessCraig_OP