Is Adjuvant Atezolizumab Safe and Effective in Muscle-Invasive Urothelial Cancer?
Posted: Tuesday, April 13, 2021
According to findings from the IMvigor010 study presented in The Lancet Oncology, treatment with the anti–PD-L1 inhibitor atezolizumab does not seem to improve survival outcomes versus observation in some patients with urothelial carcinoma. However, it did appear to be generally tolerable. Thomas Powles, MD, of Barts Cancer Institute in London, and colleagues sought to determine whether adjuvant atezolizumab may extend disease-free survival in patients with high-risk muscle-invasive urothelial carcinoma.
The phase III trial enrolled 809 patients and randomly assigned them to either atezolizumab (n = 406) or observation (n = 403). At a median follow-up of 21.9 months, median disease-free survival was comparable between the groups, at 19.4 months with atezolizumab versus 16.6 months with observation (stratified hazard ratio = 0.89 [95% confidence interval (CI) = 0.74–1.08]; P = .24).
A total of 122 patients (31%) receiving atezolizumab and 71 patients (18%) undergoing observation experienced serious adverse events, with 63 patients (16%) in the atezolizumab group having a treatment-related grade 3 or 4 event and 1 patient in that group experiencing treatment-related death. In both the atezolizumab and observation groups, urinary tract infection (31 vs. 20), pyelonephritis (12 vs. 14), and anemia (8 vs. 7) were most common.
Patients were enrolled from 192 medical facilities across 24 countries or regions. All patients had an Eastern Cooperative Oncology Group performance status between 0 and 2. Enrollment occurred within 14 weeks of radical cystectomy or nephroureterectomy with lymph node dissection. Patients received either 1,200 mg of intravenous atezolizumab every 3 weeks for 16 cycles or 1 year, whichever came first, or observation.
Disclosure: For full disclosures of the study authors, visit thelancet.com.