Biomarker-driven phase 2 umbrella trial study for patients with recurrent small cell lung cancer failing platinum-based chemotherapy.

To the best of the authors' knowledge, the current study is the first biomarker-driven umbrella study conducted in patients with recurrent SCLC. Although the current study demonstrated the limited clinical efficacy of monotherapy, novel biomarker approaches using other cell cycle inhibitor(s) or combinations warrant further investigation.