Novel PD-1 Antibody Shows Activity in Advanced Lung Cancer
Posted: Monday, December 21, 2020
The novel PD-1 inhibitor toripalimab demonstrated antitumor activity with reportedly manageable safety profiles in patients with advanced non–small cell lung cancer (NSCLC), based on the early results of a phase I trial. In addition, Jie Wang, MD, PhD, of the Chinese Academy of Medical Sciences and Peking Union Medical College, and colleagues assessed the clinical utility of JS311, an investigational PD-L1 immunohistochemistry assay, which appeared to be consistent with three commonly used PD-L1 staining assays. Their study findings were published in JAMA Network Open.
“Promising long-term survival and a durable response were observed in patients with PD-L1 expression of at least 50%, as assessed by [the] novel PD-L1 antibody JS311. These results can contribute to the diversity of anti–PD-1/PD-L1 treatment and provide an interchangeable assay for pathological practice,” stated the study investigators.
A total of 41 patients who exhibited disease progression following at least 3 lines of chemotherapy for NSCLC were enrolled. Participants were administered a single dose of toripalimab for 28 days, followed by multidose infusions every 2 weeks. PD-L1 expression in tumor biopsies were assessed via JS311 using immunohistochemistry.
Nearly 70% of patients exhibited a median progression-free survival of 2.8 months and an overall survival of 13.8 months. When comparing PD-L1 tumor proportion scores of at least 50%, 1% to 49%, and less than 1%, median progression-free survival was 11.2 months, 2.3 months, and 2.8 months, respectively.
To verify the efficacy of JS311, three other anti–PD-L1 assays (22C3, 28-8, and SP263) were compared during staining using 280 tumor specimens. Consistency between antibodies was between 80.8% and 89.5% for tumor proportion scores of 1% and between 93.3% and 95.5% for PD-L1 tumor proportion scores of 50%.
The most common treatment-related adverse effects were rash (14.6%) and increased amylase levels (12.2%). A total of 18 patients (43.9%) experienced at least one treatment-related adverse event.
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.
