Wilmington, Del. — AstraZeneca said a combination of Imfinzi, or durvalumab, and Amgen’s tarlatamab significantly improved overall survival in patients with extensive-stage small cell lung cancer in the Phase 3 DeLLphi-305 trial.
The planned interim analysis showed that Imfinzi plus tarlatamab produced a statistically significant and clinically meaningful improvement in overall survival compared with Imfinzi alone when used as first-line maintenance therapy.
The study enrolled patients whose disease had not progressed after initial treatment with Imfinzi combined with platinum chemotherapy, using either carboplatin or cisplatin, and etoposide.
The combination also produced statistically significant and clinically meaningful improvements in progression-free survival and objective response rate, according to AstraZeneca.
Extensive-stage small cell lung cancer is an aggressive form of lung cancer characterized by rapid tumor growth and spread to other organs, including the brain and liver. About 195,000 people worldwide are expected to be treated for the disease in 2026.
Immune checkpoint inhibitors such as Imfinzi have improved survival and become part of the first-line standard of care for extensive-stage small cell lung cancer. However, many patients still experience disease progression, and median overall survival with current standard treatment is approximately one year.
“These results show that IMFINZI-based induction therapy followed by maintenance treatment with IMFINZI plus tarlatamab demonstrates an unprecedented improvement in overall survival for patients with this highly aggressive form of lung cancer,” said Susan Galbraith, Executive Vice President, Oncology Haematology R&D at AstraZeneca.
“IMFINZI continues to reshape how lung cancer is treated, establishing new standards of care across multiple settings, and these new findings further underscore its role as the backbone immunotherapy of choice for small cell lung cancer.”
Jacob Sands, M.D., Associate Chief of the Lowe Center for Thoracic Oncology at Dana-Farber Cancer Institute, said many patients with small cell lung cancer relapse rapidly on existing therapies and may never reach second-line treatment.
“In my career treating people with extensive-stage small cell lung cancer, these are among the most compelling survival results I have seen, indicating the potential to reshape the natural history of small cell lung cancer,” Sands said.
“DeLLphi-305 represents an unprecedented milestone and suggests we may be entering a new era where meaningfully longer survival is possible for more patients.”
The safety and tolerability profile of the Imfinzi-tarlatamab combination was consistent with the known profiles of the individual treatments, with no new safety signals identified, AstraZeneca said.
The company plans to present detailed results from DeLLphi-305 at an upcoming medical meeting and share the data with regulatory authorities worldwide.
Imfinzi is approved in the United States, European Union, Japan, China and other countries for extensive-stage small cell lung cancer and limited-stage small cell lung cancer based on results from the Phase 3 CASPIAN and ADRIATIC trials, respectively.
