Real-world outcomes of immunotherapy rechallenge in extensive-stage small cell lung cancer

Immunochemotherapy can induce responses in patients with extensive-stage small cell cancer (ES-SCLC), but most patients experience relapse and resistance after initial treatment. A retrospective study at Central South University (Changsha, China) evaluated ICI rechallenge for these patients. Among 151 patients with progression after first-line immunochemotherapy between September 2019 and April 2025, patients who received ICI rechallenge, compared with patients who did not, had higher objective response rate (26.0% versus 11.8%; p=0.043) and disease control rate (75.0% versus 47.1%; p<0.001), as well as longer median second progression-free survival (3.98 versus 2.43 months; p<0.001) and median overall survival (9.43 versus 6.23 months; p<0.001). First-line progression-free survival longer than 6 months, ICI rechallenge, and receipt of third- or later-line therapy were independently associated with improved outcomes. The incidence of grade ≥ 3 treatment-related adverse events did not differ significantly between the two groups. In the ICI rechallenge group, immune-related adverse events were mostly grade 1 or 2; grade 3 irAEs occurred in only 2.0% of patients. The authors conclude that ICI rechallenge significantly improved outcomes in ES-SCLC patients with progression after first-line immunochemotherapy.