Durvalumab Wins FDA Priority Review in Small Cell Lung Cancer

• The FDA has granted priority review to the supplemental biologics license application (sBLA) for durvalumab (Imfinzi) for the treatment of limited-stage small cell lung cancer (LS-SCLC).
• This is supported by data from the phase 3 ADRIATIC study (NCT03703297).
• The Prescription Drug User Fee Act target action date is expected in the fourth quarter of 2024.

The sBLA of the PD-1/PD-L1 immune checkpoint inhibitor durvalumab has been granted priority review for the treatment of LS-SCLC, with a decision on approval expected in the fourth quarter of 2024.¹

Durvalumab was also granted an FDA breakthrough therapy designation in this setting, which expedites the development and review of drugs that address significant unmet needs.

“This priority review reinforces the potential [durvalumab] to transform outcomes for patients as the first and only immunotherapy to demonstrate a survival benefit in limited-stage small cell lung cancer. There is an urgent need for new treatment options that improve upon the standard of care in this setting, which has not changed in forty years, and we look forward to working with the FDA to bring [durvalumab] to patients as quickly as possible,” said Susan Galbraith, executive vice president of oncology research and development at AstraZeneca, in a press release.

About the Phase 3 ADRIATIC Trial of Durvalumab in LS-SCLC

The sBLA is supported by data from the phase 3 ADRIATIC trial that were presented at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting. Here, durvalumab reduced the risk of death by 27% vs placebo (HR, 0.73; 95% CI, 0.57-0.93; P =.0104). The estimated median overall survival was 55.9 months with durvalumab (95% CI, 37.3-not estimable) vs 33.4 months (95% CI, 25.5-39.9) with placebo. An estimated 57% of patients treated with durvalumab were alive at 3 years vs 48% with placebo.^1,2

Further, the risk of disease progression or death was lowered by 24% (HR, 0.76; 95% CI, 0.61-0.95; P =.0161) with durvalumab compared with placebo. The median progression-free survival was 16.6 months (95% CI, 10.2-28.2) vs 9.2 months (95% CI, 7.4-12.9) with durvalumab vs placebo, respectively. At 2 years, 46% and 34% of patients on durvalumab and placebo, respectively, had not experienced disease progression.2

“I think this establishes a new standard-of-care for the treatment of limited-stage small cell lung cancer. That is, chemotherapy and radiation should continue to be the core treatment of those patients. But after that is completed and patients are safe, and there are no other issues, they should go on to receive up to 2 years of durvalumab given monthly because of these benefits that have been seen in this study,” said David Spigel, MD, chief scientific officer at Sarah Cannon Research Institute and first author of the study, in an interview with Targeted Oncology^TM.

“This is only the beginning of being able to study novel immunotherapies and combination immunotherapies. The ADRIATIC still has not read out its combination arm of durvalumab plus tremelimumab [Imjudo], and there are a whole number of other investigational studies that are seeking to improve on this,” said Missak Haigentz, MD, professor of medicine at Rutgers Robert Wood Johnson Medical School, chief of Thoracic and Head and Neck Medical Oncology at the Rutgers Cancer Institute, in an interview with Targeted Oncology^TM.

REFERENCES:

1. Imfinzi granted priority review and breakthrough therapy designation for patients with limited-stage small cell lung cancer in the US. News release. AstraZeneca. August 15, 2024. Accessed August 15, 2024. https://tinyurl.com/2vsfvykf

2. Spigel D, Cheng Y, Cho B, et al. ADRIATIC: durvalumab (D) as consolidation treatment (tx) for patients (pts) with limited-stage small-cell lung cancer (LS-SCLC). J Clin Oncol. 2024;42(suppl 17):abstr LBA5. doi:10.1200/JCO.2024.42.17_suppl.LBA5