FDA Approves Durvalumab for Limited-Stage SCLC

Durvalumab (Imfinzi, AstraZeneca) is now approved for adults with limited-stage small cell lung cancer (LS-SCLC) whose disease has not progressed after treatment with concurrent platinum-based chemotherapy and radiation therapy.

The US Food and Drug Administration approval makes the monoclonal antibody — which is already approved for multiple tumor types — the first immunotherapy regimen approved in this setting, AstraZeneca noted in a press release.

“Durvalumab is the first and only systemic treatment following curative-intent, platinum-based chemoradiotherapy to show improved survival for patients with this aggressive form of lung cancer,” international coordinating investigator on the trial, Suresh Senan, PhD, stated in the press release. “This finding represents the first advance for this disease in four decades.”

Approval, which followed Priority Review and Breakthrough Therapy Designation, was based on findings from the phase 3 ADRIATIC trial showing a 27% reduction in the risk for death with durvalumab vs placebo.

Findings from the trial were reported during a plenary session at the 2024 American Society of Clinical Oncology conference, as reported at the time by Medscape Medical News, and subsequently published in The New England Journal of Medicine.

In 730 patients with LS-SCLC who were randomized 1:1:1 to receive single-agent durvalumab, durvalumab in combination with tremelimumab, or placebo, overall survival (OS) and progression-free survival (PFS) were significantly improved with durvalumab alone vs placebo (hazard ratio, 0.73 and 0.76, for OS and PFS, respectively). Median OS was 55.9 months vs 33.4 months with durvalumab vs placebo, and PFS was 16.6 vs 9.2 months, respectively.

Senan, a professor of clinical experimental radiotherapy at the Amsterdam University Medical Center, Amsterdam, the Netherlands, noted, in the press release that 57% of patients were still alive at 3 years after being treated with durvalumab, which underscores the practice-changing potential of this medicine in this setting.

“This new treatment option is a game changer for patients with limited-stage small cell lung cancer, a disease known for its high rate of recurrence,” Dusty Donaldson, founder and executive director of the nonprofit advocacy organization LiveLung, stated in the release. “Historically, more often than not, clinical trials to identify new treatment options for this type of cancer have failed to show benefit. We are therefore so excited that many more people will now have the opportunity to access this immunotherapy treatment that holds the potential to significantly improve outcomes.”

Adverse reactions occurring in at least 20% of patients in the ADRIATIC trial included pneumonitis or radiation pneumonitis and fatigue.

The recommended durvalumab dose, according to prescribing information, is 1500 mg every 4 weeks for patients weighing at least 30 kg and 20 mg/kg every 4 weeks for those weighing less than 30 kg, until disease progression or unacceptable toxicity or a maximum of 24 months.

Sharon Worcester, MA, is an award-winning medical journalist based in Birmingham, Alabama, writing for MedscapeMedical News, MDedge, and other affiliate sites. She currently covers oncology, but she has also written on a variety of other medical specialties and healthcare topics. She can be reached atsworcester@mdedge.com or on X:@SW_MedReporter.