Phase I Study of Anti–PD-1 Antibody in Advanced Melanoma
Posted: Wednesday, January 30, 2019
According to the results of a first-in-human dose-escalation study, the anti–PD-1 monoclonal antibody JS001 appears to have clinical activity in patients with advanced melanoma or urologic cancer who are refractory to standard systemic therapy. Participants with an immune-active profile in the tumor microenvironment or in peripheral blood responded to JS001, based on the phase I trial results published in the Journal of Hematology & Oncology.
“JS001 was well tolerated and demonstrated promising antitumor activity in [urothelial carcinoma] and [renal cell carcinoma] as well as in previously underexplored acral and mucosal melanoma subtypes,” stated Bixia Tang, MD, of the Peking University Cancer Hospital & Institute in Beijing, China, and colleagues.
A total of 36 patients received a single-dose, intravenous infusion of JS001 followed by multiple dose infusions every 2 weeks. Participants had advanced melanoma (n = 22) or urologic cancer (n = 14). Of the patients with melanoma, 14 had an acral subtype and 4 had a mucosal subtype, neither of which were associated with chronic exposure to ultraviolet light.
A complete response was reported in 1 patient, partial responses were observed in 7 patients, and 10 patients had stable disease. The objective response rate was 22.2%, and the disease control rate was 50.0%. The researchers found that clinical responses correlated with several factors, including PD-L1 expression on tumor cells, the presence of tumor-infiltrating lymphocytes, baseline tumor volume, and a high percentage of activated CD8-positive T cells.
As for safety, JS001 was reported to be well tolerated, and no dose-limiting toxicity was observed. Grade 3 or 4 treatment-related adverse events occurred in 36% of patients.
Disclosure: The study authors reported no conflicts of interest.