Locally Advanced NSCLC: Pembrolizumab Plus Risk-Adapted Radiotherapy Under Study

By: Amy MacDonald, MS
Posted: Tuesday, March 19, 2024

Emerging data suggest that including anti–PD-1 or anti–PD-L1 immunotherapy may offer benefits over traditional chemoradiotherapy protocols for patients with locally advanced non–small cell lung cancer (NSCLC). To explore this hypothesis, Nitin Ohri, MD, MS, of Montefiore Einstein Comprehensive Cancer Center, New York, and colleagues evaluated the use of the PD-1 inhibitor pembrolizumab in combination with standard radiotherapy. Published in the Journal of Clinical Oncology, their data from the prospective, multi-institutional SPRINT trial demonstrated that induction/consolidation radioimmunotherapy, in the absence of traditional chemotherapy, may be beneficial in patients whose advanced NSCLC features high tumor PD-L1 expression. Although other clinical trials have also omitted chemotherapy in similar populations, this trial was unique in its inclusion of induction immunotherapy.

“As expected, our deintensified treatment regimen was tolerated well. Clinical outcomes thus far have exceeded expectations, supporting further investigation of this treatment strategy,” the investigators noted.

This modestly sized, nonrandomized trial enrolled 25 patients with locally advanced stage II to III NSCLC (and a PD-L1 tumor proportion score > 50%) in the immunotherapy arm. These patients’ outcomes were compared with 12 patients who received standard-of-care chemoradiotherapy. In the immunotherapy arm, three cycles of induction pembrolizumab (200 mg, once every 21 days) were followed by 20 daily fractions of personalized radiation over 4 weeks (48–55 Gy). They then received consolidation pembrolizumab, beginning 4 weeks after radiotherapy, for up to 1 year.

The primary study endpoint of 1-year progression-free survival was met, with 76% of the 25 patients alive at 1 year. The secondary endpoints of overall survival at 1 year (92% of 25 patients) and 2 years (76% of 25 patients) were also met. Two patients (8%) experienced grade 3 colitis, and two patients (8%) experienced grade 3 esophagitis.

Disclosure: For full disclosures of the study authors, visit ascopubs.org.

Journal of Clinical Oncology