Bjørn Grønberg, MD, Norwegian University of Science and Technology, Trondheim, Norway, shares the results of a phase 2 clinical trial which analyzed the impact of atezolizumab following chemoradiotherapy (CRT) for patients with limited-stage small cell lung cancer (SCLC).

The results of this analysis demonstrated similar response rates and survival outcomes between atezolizumab and controls. Dr Grønberg stated, “Unfortunately, we don't have any predictive biomarkers for the treatment of SCLC, let's see if we can find anything in the translation research based on the material collected from this trial.”

Dr Grønberg presented these results at the 2025 American Society of Clincial Oncology (ASCO) Meeting in Chicago, Illinois.

Transcript:

Hi, my name is Bjørn Grønberg. I'm a professor and consultant in oncology in Trondheim, Norway.

At this year's ASCO meeting, it's been my pleasure to present results of our European randomized phase 2 trial investigating whether atezolizumab immunotherapy prolonged survival in patients who have completed chemoradiotherapy in limited stage small cell lung cancer.

The background is that concurrent chemoradiotherapy has been a standard treatment for these patients for quite a long time. We haven't seen much improvement, but we have seen that adding immunotherapy to chemotherapy improved survival in extensive stage small cell lung cancer. We've also seen that immunotherapy after chemoradiotherapy, prolonged survival in non-small cell lung cancer. That was the background for doing this trial in which patients were randomized 1 to 1 to receive 1 year of atezolizumab after chemoradiotherapy or observation, which was the current standard care.

We saw that the patients tolerated the treatment. There was some toxicity, but manageable, 35% of the patients completed the whole year of treatment.

Unfortunately, we did not see any benefits in term of progression-free survival or survival, which was the primary endpoint, which is a bit curious since we had positive results of the ADRIATIC trial last year with quite a similar design. There are some differences in patient selection and also the backbone treatment, the chemoradiotherapy. We need to explore that further until we can really know how to select patients for chemoradiotherapy, for immunotherapy, and also to predict the treatment outcomes and maybe also toxicity.

Overall, I would say that this trial adds to previous studies showing that this treatment is tolerable. We will look into subgroups. We have seen that there was actually a big difference in effect between women and men, also between those who received carboplatin versus those who received cisplatin. Unfortunately, we don't have any predictive biomarkers for the treatment of small cell lung cancer, let's see if we can find anything in the translation research based on the material collected from this trial.

Thank you for your attention.

Source:

Grønberg B, Aanerud M, Dumoulin D, et al. Randomized phase II trial investigating whether atezolizumab after chemoradiotherapy (CRT) prolongs survival in limited stage (LS) small cell lung cancer (SCLC). Presented at 2025 ASCO Annual Meeting. May 30-June 3, 2025; Chicago, IL. Abstract LBA8005.