Imfinzi showed a sustained overall survival benefit in 1st-line extensive-stage small cell lung cancer in the Phase III CASPIAN trial
ASCO data show more than 10% of patients on Imfinzi plus chemotherapy had not progressed and remained on treatment at two years vs. 2.9% on chemotherapy alone
Detailed results from an updated analysis of the Phase III CASPIAN trial showed AstraZeneca?s?Imfinzi?(durvalumab) in combination with a choice of chemotherapies, etoposide plus either carboplatin or cisplatin, demonstrated a sustained, clinically meaningful overall survival (OS) benefit for adults with extensive-stage small cell lung cancer (ES-SCLC) treated in the 1st-line setting.
The CASPIAN trial met the primary endpoint of OS in?June 2019, reducing the risk of death by 27% (based on a hazard ratio [HR] of 0.73; 95% confidence interval [CI] 0.59-0.91; p=0.0047) which formed the basis of the US FDA approval in?March 2020.
After a median follow up of more than two years, the latest results for?Imfinzi?plus chemotherapy showed sustained efficacy, maintaining a 25% reduction in the risk of death versus chemotherapy alone (based on an HR of 0.75; 95% CI 0.62, 0.91; nominal p=0.0032). Updated median OS was 12.9 months versus 10.5 for chemotherapy. In a post-hoc analysis, an estimated 22.2% of patients treated with?Imfinzi?plus chemotherapy were alive at 24 months versus 14.4% for chemotherapy.
For?Imfinzi?plus chemotherapy, 11% of patients were alive and progression-free at 24 months versus 2.9% for chemotherapy alone (post-hoc).?Imfinzi?plus chemotherapy maintained a high confirmed objective response rate (ORR) (68% versus 58%) and in a post-hoc analysis, duration of response (DoR) for?Imfinzi?at 24 months was 13.5% versus 3.9% for chemotherapy. At 24 months, 12% of patients in the?Imfinzi?plus chemotherapy arm remained on?Imfinzi?treatment.
Luis Paz-Ares MD, Ph.D., Chair, Medical Oncology Department, Hospital Universitario Doce de Octubre, Madrid, Spain and principal investigator in the Phase III CASPIAN trial said: ?These updated results from the CASPIAN trial show a remarkable 22% of patients still alive at 24 months, supporting the sustained benefits of treatment with?Imfinzi?plus chemotherapy. This is an effective 1st-line treatment in the extensive-stage setting, where improving outcomes has been a challenge and so few patients survive five years.?
Jos? Baselga, Executive Vice President, Oncology R&D, said: ?After two years median follow-up,?Imfinzi?continues to show sustained and meaningful improvements in survival and prolonged treatment response for patients facing this devastating and aggressive disease. These data reinforce?Imfinzi?plus chemotherapy as an important new standard of care for extensive-stage small cell lung cancer patients, and this regimen offers patients convenient dosing every four weeks during maintenance. We look forward to bringing the benefits of?Imfinzi?to patients around the world.?
The second experimental arm in the CASPIAN trial testing tremelimumab, an anti-CTLA4 monoclonal antibody, added to?Imfinzi?and chemotherapy showed a trend towards OS, but did not reach statistical significance compared to chemotherapy alone.
Summary of updated results:
Data cut-off date was 27 January 2020. Formal statistical analysis was completed at the time of the interim analysis per trial protocol. Therefore, no formal testing for statistical significance could be performed in this updated analysis.
Adrian Kemp Company Secretary AstraZeneca PLC