|The following article features coverage from the American Society of Clinical Oncology 2019 meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Pembrolizumab may substantially increase overall survival in patients with advanced non-small cell lung cancer (aNSCLC), according to research presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.
In the phase 1b KEYNOTE-001 study of patients with the condition who received pembrolizumab, the overall survival rate at 5 years was 23.2% for those who had not previously been treated with chemotherapy and 15.5% for those who had previously been treated with chemotherapy (ClinicalTrials.gov Identifier: NCT01295827). These overall survival rates are higher than the historical rates of about 5% prior to the introduction of immunotherapy, the authors noted.
The study involved 550 patients with aNSCLC including 101 patients who had not received any prior treatment and 449 patients who had received treatment. The researchers collected contemporaneous tumor samples from the patients for PD-L1 evaluation. Starting in 2011, each patient received 2 mg/kg of pembrolizumab every 3 weeks or 10 mg/kg of the drug every 2 or 3 weeks. In recent years, the researchers changed the protocol to a single dose of 200 mg per patient regardless of body weight every 3 weeks.
The median follow-up was 60.6 months — a time period of about 5 years. Overall survival at that point was 18% (100 patients were still alive).
Having higher levels of PD-L1 expression was linked to longest survival; among study participants who had not received prior treatment, the overall survival rate at 5 years was 29.6% for those with PD-L1 expression of 50% or more compared with 15.7% for those with PD-L1 expression below 50%. Among participants who had received prior treatment, the overall survival rate was 25% for those with PD-L1 expression of 1 to 49% compared with 3.5% for those with PD-L1 expression below 1%.
The investigators also found that 17% of all study participants experienced immune-mediated adverse events at 5 years. The most common adverse event was hypothyroidism, and the most serious one was pneumonitis.
“The uniformly negative outlook that has been associated with a diagnosis of advanced non-small cell lung cancer is certainly no longer appropriate,” lead study author Edward B. Garon, MD, MS, associate professor of medicine at the David Geffen School of Medicine at UCLA, said in a statement. “The fact that we have patients on this trial that are still alive after 7 years is quite remarkable. We also have evidence that most patients who are doing well after 2 years on pembrolizumab live for 5 years or more.”
Read more of Cancer Therapy Advisor‘s coverage of ASCO’s annual meeting by visiting the conference page.
Garon EB, Hellmann MD, Carcereny Costa E. Five-year long-term overall survival for patients with advanced NSCLC treated with pembrolizumab: Results from KEYNOTE-001. Presented at: 2019 American Society of Clinical Oncology (ASCO) Annual Meeting; May 31-June 4, 2019; Chicago, IL. Abstract LBA9015.