Dr Spigel on the Efficacy of Durvalumab Consolidation Therapy in LS-SCLC

David R. Spigel, MD, chief scientific officer, Sarah Cannon Research Institute, discusses findings from the first planned interim analysis of the phase 3 ADRIATIC trial (NCT03703297) in patients with limited-stage small cell lung cancer (LS-SCLC).

ADRIATIC evaluated durvalumab (Imfinzi; n = 264) vs placebo (n = 266) as consolidation therapy in patients with LS-SCLC who had received prior concurrent chemoradiotherapy. The coprimary end points of the trial were overall survival (OS) and progression-free survival (PFS) by blinded independent central review, Spigel states.

This trial met both primary end points, he reports. At a median follow-up of 37.2 months (range, 0.1-60.9) in censored patients, durvalumab elicited an OS benefit over placebo. The median OS was 55.9 months (95% CI, 37.3-not evaluable) with durvalumab vs 33.4 months (95% CI, 25.5-39.9) with placebo, resulting in a 27% reduction in the risk of death (HR, 0.73; 95% CI, 0.57-0.93; P = .0104). In the durvalumab arm (n = 264), the 24- and 36-month OS rates were 68.0% and 56.5%, respectively. These values were 58.5% and 47.6%, respectively, in the placebo arm (n = 266).

Furthermore, at a median follow-up of 27.6 months (range, 0.0-55.8) in censored patients, durvalumab generated a median PFS of 16.6 months (95% CI, 10.2-28.2) vs 9.2 months (95% CI, 7.4-12.9), respectively. This translated to a 24% reduction in the risk of death or disease progression (HR, 0.76; 95% CI, 0.61-0.95; P = .0161), Spigel adds. In the durvalumab arm, the 24- and 36-month OS rates were 48.8% and 46.2%, respectively. These values were 36.1% and 34.2%, respectively, in the placebo arm.

Notably, ADRIATIC also enrolled patients to a third arm, where they received dual checkpoint inhibition with durvalumab plus the CTLA-4 inhibitor tremelimumab-actl (Imjudo), Spigel says. Future data readouts from this trial will include findings from an analysis of the durvalumab/tremelimumab arm vs the placebo arm, although those data are currently blinded, Spigel concludes.