Survival advantage suggested in responders to immunotherapy for uveal melanoma
A possible survival advantage in patients with metastatic uveal melanoma who respond to treatment with pembrolizumab is suggested in a study of the anti-PD-1 monoclonal antibody as immunotherapy for advanced disease.
Researchers enrolled 17 patients with metastatic uveal melanoma in a prospective observational cohort single-arm study to investigate efficacy and safety of pembrolizumab as a first line-therapy. Endpoints were progression-free survival, complete or partial response or disease stabilization, clinical benefit, overall survival and tolerability.
A median of eight cycles of intravenous 2 mg/kg pembrolizumab every 3 weeks was administered. Range of administration cycles was two to 28, until disease progression, toxicity or withdrawal of consent. Toxicity was reported to be mild.
Two patients achieved a partial response and were without progression after 19.4 and 28.9 months (response rate, 11.7%). Both patients were still on treatment at the time of data analysis. Disease stabilized in six patients and progressed in nine. Eight of the 17 patients (47%) were deemed to have achieved clinical benefit.
Progression-free survival was 3.8 months for all patients, 9.7 months for patients whose interval between diagnosis of primary tumor to metastatic disease was longer than 5 years, and 2.6 months for patients whose same interval was less than 5 years.
“Based on our data, relapse after 5 years from the diagnosis of primary tumor could be considered a parameter to select patients who may benefit more from immunotherapy,” the authors said. “[T]he identification of predictive factors for response is crucial.” – by Robert Linnehan
Disclosures: The authors report no relevant financial disclosures.