Compared with historical data, the addition of pembrolizumab after locally ablative therapy (LAT) improved clinical outcomes for patients with oligometastatic non-small cell lung cancer (NSCLC), according to the results of a single-arm phase 2 trial (ClinicalTrials.gov identifier: NCT02316002). The trial results were recently published in JAMA Oncology.
The trial enrolled 51 patients with oligometastatic NSCLC (which was defined as patients who had no more than 4 metastases) who had undergone LAT of any type, including surgery, chemoradiotherapy, stereotactic radiotherapy, interventional ablation, or a combination of types. Of the 51 patients, 45 actually received pembrolizumab after completing LAT. Efficacy was measured using PFS from the time of LAT initiation and PFS from the time of pembrolizumab initiation.
The median age of the study population at the time of enrollment was 64 years (range, 46-82 years), and most patients had 1 (62%) or 2 metastases (31%), with the most common metastatic sites being lung (31%) and brain (36%). Most patients were former smokers (78%), and the median number of cycles of pembrolizumab received was 11 (range, 1-16 cycles).
At approximately 2 years of follow-up, the median PFS from the time of LAT initiation was significantly longer than that seen in the historical data (19.1 vs 6.6 months, respectively; 95% CI, 9.4-28.7 months; P =.005). A more conservative measure, the median PFS from the time of pembrolizumab initiation was 18.7 months (95% CI, 10.1-27.1 months), which was longer than that seen in KEYNOTE-010 (4 months) and KEYNOTE-042 (7.1 months).
A safety analysis of pembrolizumab revealed “no new safety signals,” according to the study authors.
“Pembrolizumab after LAT for oligometastatic NSCLC appears to improve PFS with no reduction in quality of life,” the study authors wrote in conclusion. “This treatment approach warrants further testing in a randomized clinical trial.”
- Bauml JM, Mick R, Ciunci C, et al. Pembrolizumab after completion of locally ablative therapy for oligometastatic non-small cell lung cancer: a phase 2 trial [published online July 11, 2019]. JAMA Oncol. doi: 10.1001/jamaoncol.2019.1449