Bjorn Henning Gronberg, MD, PhD, on SCLC: Adjuvant Immunotherapy After CRT

We enrolled 216 patients at 37 hospitals in six countries of Europe, and out of those, 170 patients were randomized to receive either one year of atezolizumab or observation. The main endpoint was overall survival, and unfortunately we did not see any signal of an effect, neither for progression-free survival, so this is clearly a negative trial. Looking at subgroups, we do see that there are some differences in the effect depending on gender. Among women, patients on the observation arm lived much longer than expected, while among men there appears to be a signal of an effect. We also see that the choice of platinum had some influence on the survival curves. We see that among patients who received carboplatin, maybe there's a signal of an effect quite similar to what we actually saw also in the ADRIATIC trial. Median treatment time was 8 courses. Overall, there were more side effects in the experimental arm, but maybe not any single adverse event—it's more the totality. On the other hand, patients on the observation arm didn't meet the investigators as often as the patients who came regularly for infusions of atezolizumab. I think overall this study shows that the concept of adding checkpoint inhibitors after chemoradiated therapy in limited-stage small cell lung cancer is tolerable, even if this intervention did not prolong PFS or overall survival.