IMFINZI® (durvalumab) receives Priority Review and Breakthrough Therapy Designation for limited-stage small cell lung cancer in the US

AstraZeneca announced that the U.S. Food and Drug Administration (FDA) has accepted its supplemental Biologics License Application (sBLA) for IMFINZI® (durvalumab). This decision, which is based on the positive results from the ADRIATIC Phase III trial, pertains to patients with limited-stage small cell lung cancer (LS-SCLC) whose disease has not progressed following platinum-based concurrent chemoradiotherapy (cCRT). The FDA has also granted Priority Review to the application, recognizing the potential of IMFINZI to significantly improve treatment outcomes over existing options.

Priority Review is a designation given by the FDA to applications for medicines that, if approved, would offer significant improvements in terms of safety, efficacy, or patient compliance. The Prescription Drug User Fee Act date, which is the target date for the FDA’s regulatory decision, is expected in the fourth quarter of 2024. Additionally, IMFINZI received Breakthrough Therapy Designation (BTD) from the FDA in this setting, aimed at accelerating the development and review process for promising new treatments intended for serious conditions with unmet medical needs.

Small cell lung cancer (SCLC) is an aggressive type of lung cancer known for its rapid recurrence and progression despite initial responsiveness to chemotherapy and radiotherapy. The prognosis for patients with LS-SCLC remains grim, with only 15-30% surviving five years post-diagnosis. The ADRIATIC Phase III trial highlighted that IMFINZI reduced the risk of death by 27% compared to placebo and demonstrated a median overall survival of 55.9 months versus 33.4 months for placebo. Furthermore, at three years, 57% of patients treated with IMFINZI were alive compared to 48% on placebo.

The trial also showed that IMFINZI reduced the risk of disease progression or death by 24% relative to placebo. The median progression-free survival was 16.6 months for IMFINZI-treated patients versus 9.2 months for those on placebo. At the two-year mark, 46% of patients receiving IMFINZI had not experienced disease progression compared to 34% on placebo. The safety profile of IMFINZI was generally manageable and in line with its known characteristics, with no new safety concerns identified.

Susan Galbraith, Executive Vice President, Oncology R&D at AstraZeneca, emphasized the potential of IMFINZI to transform patient outcomes as the first immunotherapy to demonstrate a survival benefit in LS-SCLC. She pointed out the urgent need for new treatment options that surpass the current standard of care, which has seen little change in the past four decades.

The ADRIATIC trial is a global, multi-center Phase III study evaluating IMFINZI, both as monotherapy and in combination with IMJUDO® (tremelimumab-actl), against placebo in patients with LS-SCLC after cCRT. The study's primary goals were progression-free survival (PFS) and overall survival (OS) for IMFINZI monotherapy. Key secondary endpoints included OS and PFS for the combination treatment, along with safety and quality of life assessments. The trial involved 730 patients across 164 centers in 19 countries.

IMFINZI, a human monoclonal antibody, works by binding to the PD-L1 protein and inhibiting its interaction with PD-1 and CD80 proteins, thereby countering the tumor's immune evasion tactics and promoting immune responses against the cancer. Since its first approval in 2017, IMFINZI has treated over 220,000 patients and is tested in various combinations for a broad range of cancers, including lung, breast, and gastrointestinal cancers.

AstraZeneca continues to push the boundaries in lung cancer treatment, integrating innovative approaches and new therapeutic targets. The company's comprehensive portfolio, coupled with its extensive research and development efforts, aims to improve outcomes and bring new hope to patients with various forms of cancer.