On February 16, 2018, the US Food and Drug Administration (FDA) approved durvalumab (Imfinzi, AstraZeneca Inc.) for patients with unresectable stage III non-small cell lung cancer (NSCLC) whose disease has not progressed following concurrent platinum-based chemotherapy and radiation therapy.

Approval was based on a planned interim analysis of progression-free survival (PFS) from PACIFIC (NCT02125461), a randomized, double-blind, placebo-controlled trial conducted in 713 patients with unresectable, stage III NSCLC. Patients completed concurrent platinum-based chemotherapy and radiation within 42 days prior to study drug initiation and had WHO performance status of 0 or 1. The major efficacy measures were PFS (blinded independent central review per RECIST v1.1) and overall survival (OS). With approximately 81% of planned events for the final analysis, the trial demonstrated a statistically significant improvement in PFS for durvalumab compared to placebo (HR 0.52; 95% CI: 0.42, 0.65; P<0.00010). The estimated median PFS was 16.8 months for patients receiving durvalumab and 5.6 months for those receiving placebo. The OS results were immature at the interim PFS analysis.

The most common adverse reactions (occurring in at least 20% of patients receiving durvalumab in PACIFIC) were cough, fatigue, pneumonitis/radiation pneumonitis, upper respiratory tract infections, dyspnea, and rash.

The recommended dose and schedule for durvalumab for this indication is 10 mg/kg as an intravenous infusion over 60 minutes every two weeks.