Synergy is better than my way or your way.
The Study: Granted, it’s hard for anyone to keep up with the frenzied race amongst Big Pharma-sponsored agents vying for category 1 recs in as many NCCN algorithm branches as possible. There are myriad logical conclusions to draw from what available data we do have that the addition of stereotactic body radiation (SBRT) to ICI is not only safe but very likely synergistic. In other words, seems low-risk high-reward. But for those loathe to extrapolate, we now have a phase 2 trial of 76 patients receiving pembrolizumab for recurrent metastatic non-small cell lung cancer (NSCLC) randomized to +/- the addition of 8 Gy x 3 SBRT to a single site of disease prior to pembro initiation. The primary endpoint of interest was objective response at 12 weeks with a hypothesis that SBRT would work to enhance the efficacy of pembro. Indeed, objective response rates were doubled from 18 → 36% with SBRT, with no increase in adverse events. What’s more, median progression-free survival was increased from 2 → 7 months. Most interesting, the most pronounced benefit was seen for tumors with no PD-L1 expression.
TBL: Inserting a quick shot of SBRT prior to pembro for refractory NSCLC is clearly safe and may double response rates, suggesting it is more practical than not to extrapolate Gomez data in the setting of pembro. | Theelen, JAMA Oncol 2019