FDA Approves Adjuvant Pembrolizumab for Non–Small Cell Lung Cancer

The FDA has approved pembrolizumab (Keytruda, Merck) as a single agent for adjuvant treatment following surgical resection and platinum-based chemotherapy for adults with stage IB (T2a ≥4 cm), II, or IIIA non–small cell lung cancer (NSCLC).¹ The approval makes pembrolizumab the only immunotherapy approved for NSCLC regardless of PD-L1 expression in both the adjuvant and metastatic settings.

“While there have been many advances for patients with metastatic disease, surgery remains the typical treatment for people with stage IB, II and IIIA non-small cell lung cancer. Unfortunately, many of these patients who undergo surgery still see their disease return,” Roy S. Herbst, MD, PhD, deputy director and chief of medical oncology, Yale Cancer Center and Smilow Cancer Hospital and ensign professor of medicine and professor of pharmacology, Yale School of Medicine, said in a press release. “Today’s approval for Keytruda offers a new, important immunotherapy treatment option for stage IB (T2a ≥4 cm), II, or IIIA patients with non-small cell lung cancer following surgery and adjuvant chemotherapy. This provides, for the first time, an adjuvant immunotherapy treatment option for non-small cell lung cancer patients with stage IB disease and regardless of PD-L1 expression.”

The approval of the anti-PD-1 agent was based on findings from the multicenter, randomized, triple-blind, placebo-controlled, KEYNOTE-091 trial, (NCT02504372). In the trial, the median investigator-assessed disease-free survival (DFS) was 58.7 months (95% CI, 39.2-not reached [NR]) in the pembrolizumab cohort compared with 34.9 months (95% CI, 28.6-NR) in the placebo cohort (HR, 0.73; 95% CI, 0.60-0.89) in patients administered adjuvant chemotherapy.² An exploratory subgroup analysis of 167 patients who were not administered adjuvant chemotherapy showed a DFS hazard ratio of 1.25 (95% CI, 0.76-2.05).

In the KEYNOTE-091 trial, investigators randomized 1177 patients 1:1 who could not have received neoadjuvant radiotherapy or chemotherapy to receive either pembrolizumab 200 mg or placebo intravenously every 3 weeks for up to 1 year. Among the randomized 1177 patients, 86% were administered adjuvant platinum-based chemotherapy following complete resection.

The primary end point was DFS, with an additional outcome measure of overall survival (OS).

Among 1010 patients administered adjuvant platinum-based chemotherapy, the median age was 64 years (range, 35-84) and 49% were 65 years of age or older; 68% were male, 77% were White, 18% were Asian, 86% were current or former smokers; and 39% of patients had an ECOG performance status of 1.

Patients either had stage IB disease (11%), stage II (57%), or stage IIIA disease (31%); 39% had PD-L1 tumor positive score (TPS) less than 1% [negative], 33% had TPS 1% to 49%, and 28% had TPS 50% or higher. Fifty-two percent of patients were from Western Europe, 20% from Eastern Europe, 17% from Asia, and 11% were from the rest of the world. OS data were immature at the time of the analysis.

Many of the adverse events reported in KEYNOTE-091 were similar to what was observed in other studies evaluating single-agent pembrolizumab in other patients with NSCLC who were administered pembrolizumab as a single agent, except for hypothyroidism (22%), hyperthyroidism (11%), and pneumonitis (7%). There were 2 patients deaths attributed to myocarditis.

The recommended dose for pembrolizumab is 200 mg every 3 weeks or 400 mg every 6 weeks until disease recurrence, unacceptable toxicity, or up to 1 year.

“Six years ago, Keytruda was the first anti-PD-1 therapy approved for the first-line treatment of metastatic non-small cell lung cancer and has changed the way metastatic disease is treated. Today’s approval marks the fifth indication for Keytruda in non-small cell lung cancer and the first indication for Keytruda in patients with resected stage IB (T2a ≥4 cm), II, or IIIA disease following adjuvant chemotherapy,” said Dr. Gregory Lubiniecki, vice president, oncology global clinical development, Merck Research Laboratories, in a press release. “This is an important milestone as we continue our efforts to pursue meaningful advances for patients with non-small cell lung cancer.”

References

1. FDA Approves KEYTRUDA® (pembrolizumab) as Adjuvant Treatment Following Surgical Resection and Platinum-Based Chemotherapy for Patients With Stage IB (T2a ≥4 Centimeters), II, or IIIA Non-Small Cell Lung Cancer (NSCLC). Merck. News release. January 27, 2023.

2. Keytruda. Prescribing information. Merck; 2023. Accessed January 27, 2023.