Clinical Summary:

• Design/Population: In this randomized phase 2 trial, patients with limited-stage small cell lung cancer who completed first-line chemoradiotherapy received autologous NK cell infusion as consolidation therapy or underwent routine follow-up. 
• Key Outcomes: Autologous NK cell therapy significantly improved progression-free survival and overall survival compared with observation, with higher response maintenance and 12-month disease control.
• Clinical Relevance: Autologous NK cell therapy may provide a promising consolidation strategy, but larger multicenter studies are needed to confirm efficacy and define its role in practice.

Results from a phase 2 trial demonstrated that autologous natural killer (NK) cell infusion as consolidation therapy significantly improved survival compared with routine follow-up among patients with limited-stage small cell lung cancer (SCLC) who completed first-line chemoradiotherapy. 

These results were presented by Jiuwei Cui, MD, The First Hospital of Jilin University, Changchun, China, at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois. 

In this open-label, single-center trial, 43 patients were randomized to receive either autologous NK cell infusions once every 2 weeks for 6 courses (n = 21) or routine follow-up (n = 22). The primary end point was progression-free survival (PFS). Secondary end points included disease control, overall survival (OS), objective response rate (ORR), and safety. 

At analysis, median PFS was 11.92 months in the NK cell therapy arm and 6.5 months in the routine observation arm (hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.18 to 0.79; P = .01), with 12-month PFS rates of 42.9% and 4.5%, respectively (P < .01). When measured from completion of chemoradiotherapy, median PFS was 16.3 months in the NK cell therapy arm and 8.1 months in the routine observation arm (HR, 0.35; 95% CI, 0.17 to 0.72; P = 0.01). Median OS was 27.13 months and 15.6 months (HR, 0.41; 95% CI, 0.19 to 0.87; P = 0.02), respectively. 

Six-month disease control was maintained in 57.1% of patients in the NK cell therapy arm and 27.3% of patients in the routine observation arm. The 12-month ORR was 19% and 0%, respectively (P < .05).

Adverse events were reported in 47.6% of patients in the NK cell therapy arm and 50% of patients in the routine observation arm. Most events were grade 1/2 and were not considered related to NK cell infusion. No unexpected safety concerns were identified.

“Autologous NK cell infusion as consolidation therapy after first-line chemoradiotherapy for SCLC yielded promising preliminary PFS and OS results, with a well-tolerated safety profile,” concluded Dr Cui.

Source:

Cui J, Chen X, Bai R, et al. Autologous natural killer cell infusion as consolidation therapy after first-line chemoradiotherapy for limited-stage small-cell lung cancer: A randomized, controlled, open-label, single-center phase II clinical study. Presented at the ASCO Annual Meeting. May 29 - June 2, 2026. Chicago, Illinois. Abstract 8013.