Durvalumab plus radiotherapy shows promise in unresectable NSCLC
In the treatment of patients with programmed cell death ligand 1 (PD-L1)-positive, unresectable, and locally advanced nonsmall cell lung cancer (NSCLC), the use of durvalumab immunotherapy in combination with curative radiotherapy yields survival gains with tolerable adverse events (AEs), as shown in the results of the phase II DOLPHIN trial.
DOLPHIN included 74 patients who were recruited across 12 institutions in Japan. All patients received radiotherapy (60 Gy) plus concurrent and maintenance durvalumab immunotherapy, administered at 10 mg/kg every 2 weeks for up to 1 year.
The rate of 12-month progression-free survival (PFS), evaluated by an independent central review, was the primary endpoint. PFS was estimated using the Kaplan-Meier method. Secondary endpoints included PFS, objective response rate, treatment completion rate, and AEs.
A total of 35 patients (median age 72 years, 88.6 percent men) were included in the full analysis set of the evaluable population. The PFS rate at 12 months was 72.1 percent (90 percent confidence interval [CI], 59.1–85.1), with a median PFS of 25.6 months (95 percent CI, 13.1 months to not estimable). The median follow-up duration was 22.8 months (range, 4.3–31.8 months).
Most patients (97.1 percent) completed the scheduled radiation therapy. The confirmed objective response rate was 90.9 percent (95 percent CI, 75.7–98.1), while the treatment completion rate was 57.6 percent (95 percent CI, 39.2–74.5).
For the safety analysis, 34 patients were evaluated. Grade 3 or 4 AEs occurred in 52.9 percent of patients, while grade 5 AEs were documented in 5.9 percent. Pneumonitis or radiation pneumonitis of any grade were reported in 67.6 percent of patients.