The study that included patients with locally advanced or metastatic urothelial carcinoma (mUC) who had not received a prior treatment and who were not eligible for cisplatin-based chemotherapy, yielded an overall response rate of 24% and a median overall survival of 14.8 months.
The results were revealed during the 52nd Annual Meeting of the American Society of Clinical Oncology (ASCO).
Data from the IMvigor 210 trial could fill a gap in the treatment of patients with metastatic mUC (urinary system cancers including bladder cancer) for whom prior treatment with platinum-based chemotherapy has failed. Platinum-based chemotherapy is the current and only treatment standard for advanced disease.
The IMvigor 210 study included patients with mUC regardless of PD-L1 expression.
The first group consisted of patients not treated with previous therapies for locally advanced or mUC and who were not candidates for first-line cisplatin-based chemotherapy. The second group was made up of patients whose disease progressed during or following previous treatment with a platinum-based chemotherapy regimen.
Patients enrolled in the study received atezolizumab every 3 weeks until it was no longer effective. The co-primary endpoints were overall response rates by RECIST (Response Evaluation Criteria In Solid Tumors) criteria and per investigator-assessed modified RECIST criteria. Key secondary endpoints were duration of response, progression-free survival, overall survival, and safety.
Of those patients who responded well to the treatment, 75% continued to respond to therapy. At the time of analysis, the median duration of response had not been reached. The results also showed that 7% of all patients achieved a complete response.
The drug’s safety profile was consistent with an earlier analysis and with safety profiles of other trials evaluating atezolizumab as a single-agent.
Dr. Sandra Horning, chief medical officer and head of Global Product Development, said in a recent press release that the Tecentriq (atezolizumab) results are highly encouraging because about half of all people with the type of bladder cancer are not able to tolerate a cisplatin-based chemotherapy, and alternative treatments bring very limited duration of response.
“This is why we are particularly pleased that the majority of people who responded to Tecentriq continued to respond at the time of analysis,” Horning said.