FDA approves Imfinzi as first line treatment for extensive stage small cell lung cancer

The approval by the FDA was based on positive results from the Phase III CASPIAN trial showing Imfinzi in combination with SoC platinum-etoposide demonstrated a statistically significant and clinically meaningful improvement in overall survival (OS) versus SoC alone. SCLC is a highly aggressive, fast-growing form of lung cancer that typically recurs and progresses rapidly despite initial response to chemotherapy. The Phase III CASPIAN trial had two primary endpoints comparing experimental arms to SoC. In the Imfinzi plus SoC arm, the risk of death was reduced by 27% (equal to a hazard ratio of 0.73; 95% CI 0.59-0.91; p=0.0047), with median OS of 13.0 months versus 10.3 months for SoC alone. Results also showed an increased confirmed objective response rate in the Imfinzi plus SoC arm (68% versus 58% for SoC alone). The safety and tolerability for Imfinzi plus SoC was consistent with the known safety profiles of these medicines. The Imfinzi plus SoC data from the CASPIAN trial were published in The Lancet. The second experimental arm testing tremelimumab added to Imfinzi and SoC recently completed, but did not meet its primary endpoint. Details will be presented at a forthcoming medical meeting. The CASPIAN trial used a fixed dose of Imfinzi (1500mg) administered every three weeks for four cycles while in combination with chemotherapy and then every four weeks until disease progression. As part of a broad development programme, Imfinzi is also being tested following concurrent chemoradiation therapy in patients with limited-stage SCLC in the Phase III ADRIATIC trial with data anticipated in 2021.