Patients with metastatic urothelial cancer (mUC) have longer progression-free survival (PFS) when they receive an upfront combination of immunotherapy and chemotherapy instead of chemotherapy alone, study findings presented at the European Society for Medical Oncology (ESMO) 2019 Congress in Barcelona, Spain, suggest.
As part of the IMvigor130 trial, Enrique Grande, MD, PhD,, of MD Anderson Cancer Centre Madrid, Spain, and collaborators randomly assigned 1213 patients with untreated mUC from 35 countries to receive atezolizumab plus platinum-based chemotherapy (PBC) (arm A), atezolizumab alone (arm B), or PBC plus placebo (arm C). Coprimary efficacy end points were PFS and overall survival (arm A vs C) and overall survival (arm B vs C).
After a median follow-up period of 11.8 months, median PFS was 8.2 months in arm A and 6.3 months in arm C, a difference that corresponded to a significant 18% decreased risk of progression in arm A. An interim analysis found a trend toward improved overall survival (16.0 vs 13.4 months in arms A and C, respectively), but this was not statistically significant. Median overall survival between arms B and C also did not differ significantly (15.7 vs 13.1 months, respectively).
“Longer follow-up is needed on overall survival and we will continue to search for biomarkers to identify which patients respond best to this therapy,” Dr Grande said in an ESMO press release.
Arms A, B, and C had objective response rates of 47%, 23%, and 44%, respectively, and complete response rates of 13%, 6%, and 7%, respectively. Adverse events leading to treatment withdrawal developed in 34%, 6%, and 34% of patients, respectively.
The safety profile of the combination therapy was consistent with that observed for the individual agents, according to the investigators.
Grande E, Galsky M, Arranz Arija JA, et al. IMvigor130: efficacy and safety from a phase III study of atezolizumab (atezo) as monotherapy or in combination with platinum-based chemotherapy (PBC) vs placebo + PBC in previously untreated locally advanced or metastatic urothelial carcinoma (mUC). Presented at the Presented at the European Society for Medical Oncology 2019 Congress held September 27 to October 1 in Barcelona, Spain. Abstract LBA14_PR.