Durvalumab plus chemotherapy, without tremelimumab, extends OS in small cell lung cancer
The addition of durvalumab to a choice of standard-of-care first-line chemotherapies conferred a sustained OS benefit for patients with extensive-stage small cell lung cancer, according to topline results of a randomized phase 3 trial released by the agent’s manufacturer.
However, the addition of a second immunotherapy to durvalumab (Imfinzi, AstraZeneca) — a human monoclonal antibody that binds to PD-L1 — did not provide an OS benefit.
“We are pleased to see the sustained and meaningful survival benefit of Imfinzi for patients with small cell lung cancer after more than 2 years median follow up,” José Baselga, MD, PhD, executive vice president for oncology research and development at AstraZeneca, said in a company-issued press release. “We have already received the first global regulatory approval for Imfinzi with etoposide plus either carboplatin or cisplatin and remain on track for more approvals soon as we provide patients an important new first-line treatment option.”
The open-label, multicenter CASPIAN trial included 805 patients with extensive-stage small cell lung cancer.
Researchers assigned patients to one of three regimens: durvalumab in combination with etoposide and either carboplatin or cisplatin chemotherapy; durvalumab and chemotherapy plus a second immunotherapy, the anti-CTLA-4 monoclonal antibody tremelimumab (MedImmune/AstraZeneca); or chemotherapy alone.
Patients in the two experimental groups received four cycles of chemotherapy, whereas those in the control group received up to six chemotherapy cycles and optional prophylactic cranial irradiation.
OS in the experimental treatment groups served as primary endpoints.
As Healio previously reported, results of an interim analysis released last year showed the trial met one of its primary endpoints, as the addition of durvalumab to etoposide and either carboplatin or cisplatin conferred a significant improvement in OS.
Results of the final analysis confirmed the OS benefit.
However, the addition of durvalumab and tremelimumab to standard chemotherapy did not confer a significant improvement in OS.
The safety profiles of durvalumab and tremelimumab appeared consistent with those observed in prior studies.
Complete data will be submitted for presentation at a medical meeting.
The FDA previously approved durvalumab for treatment of patients with unresectable stage III non-small cell lung cancer who underwent chemoradiation therapy, as well as for previously treated patients with advanced bladder cancer.
Tremelimumab is under investigation as part of combination therapy for patients with small cell lung cancer, NSCLC, bladder cancer, liver cancer, and head and neck cancer.