CHICAGO – New data suggest pembrolizumab can increase 5-year overall survival (OS) for patients with advanced non–small cell lung cancer (NSCLC).
In the phase 1b KEYNOTE-001 trial, the 5-year OS rate was 23.2% in treatment-naive patients and 15.5% in previously treated patients. This is in comparison to the 5.5% average 5-year OS rate observed in NSCLC patients who receive standard chemotherapy (Noone AM et al. SEER Cancer Statistics Review, 1975-2015).
“In total, the data confirm that pembrolizumab has the potential to improve long-term outcomes for both treatment-naive and previously treated patients with advanced non–small cell lung cancer,” said Edward B. Garon, MD, of the University of California, Los Angeles.
Dr. Garon and colleagues presented these results in a poster at the annual meeting of the American Society for Clinical Oncology, and the data were simultaneously published in the Journal of Clinical Oncology.
KEYNOTE-001 (NCT01295827) enrolled 550 patients with advanced NSCLC who had received no prior therapy (n = 101) or at least one prior line of therapy (n = 449). Initially, patients received pembrolizumab at varying doses depending on body weight, but the protocol was changed to a single dose of pembrolizumab at 200 mg every 3 weeks.
At a median follow-up of 60.6 months, 100 patients were still alive. Sixty patients had received at least 2 years of pembrolizumab, 14 of whom were treatment-naive at baseline, and 46 of whom were previously treated at baseline.
Five-year OS rates were best among patients who had high PD-L1 expression, which was defined as 50% or greater.
Among treatment-naive patients, the 5-year OS rate was 29.6% in PD-L1–high patients and 15.7% in PD-L1–low patients (expression of 1% to 49%). The median OS was 35.4 months and 19.5 months, respectively.
Among previously treated patients, the 5-year OS rate was 25.0% in PD-L1–high patients, 12.6% in patients with PD-L1 expression of 1%-49%, and 3.5% in patients with PD-L1 expression less than 1%. The median OS was 15.4 months, 8.5 months, and 8.6 months, respectively.
Among patients who received at least 2 years of pembrolizumab, the 5-year OS rate was 78.6% in the treatment-naive group and 75.8% in the previously treated group. The objective response rate was 86% and 91%, respectively. The rate of ongoing response at the data cutoff was 58% and 71%, respectively.
“The safety data did not show any unanticipated late toxicity, which I consider encouraging,” Dr. Garon noted.
He said rates of immune-mediated adverse events were similar at 3 years and 5 years of follow-up. At 5 years, 17% of patients (n = 92) had experienced an immune-related adverse event, the most common of which were hypothyroidism (9%), pneumonitis (5%), and hyperthyroidism (2%).
Dr. Garon disclosed relationships with AstraZeneca, Bristol-Myers Squibb, Dracen, Dynavax, Genentech, Iovance Biotherapeutics, Lilly, Merck, Mirati Therapeutics, Neon Therapeutics, and Novartis. KEYNOTE-001 was sponsored by Merck Sharp & Dohme Corp.
SOURCES: Garon E. et al. ASCO 2019, Abstract LBA9015; J Clin Oncol. 2019 June 2. doi: 10.1200/JCO.19.00934