Powles and Rini Put ctDNA Into Perspective in Urothelial Cancer

Welcome to OncLive On Air^™! I’m your host today, Jessica Hergert.

OncLive On Air^™ is a podcast from OncLive^®, which provides oncology professionals with the resources and information they need to provide the best patient care. In both digital and print formats, OncLive covers every angle of oncology practice, from new technology to treatment advances to important regulatory decisions.

In today’s episode, we partnered with the Uromigos to speak with Thomas Powles, MBBS, MRCP, MD, director of Barts Cancer Institute, and Brian I. Rini, MD, professor of medicine and inaugural chief of Clinical Trials at Vanderbilt-Ingram Cancer Center, to discuss the correlation between circulating tumor DNA (ctDNA) positivity and survival with atezolizumab (Tecentriq) treatment in high-risk muscle-invasive bladder cancer.

In an analysis of the phase 3 IMvigor010 trial that was presented during the ESMO Immuno-Oncology Virtual Congress 2020, ctDNA positivity identified patients with high-risk muscle-invasive urothelial cancer who were likely to derive improvements in disease-free survival (DFS) and overall survival (OS) from adjuvant atezolizumab versus observation.

The DFS outcomes were similar in the ctDNA biomarker-evaluable population compared with the intention-to-treat group. However, ctDNA positivity served as a poor prognostic marker for DFS and OS, with hazard ratios of 6.30 and 8.00, respectively.

When comparing atezolizumab and observation in ctDNA-positive patients, however, the median DFS was 5.9 months and 25.8 months, respectively, and the median OS was 25.8 months and 15.8 months, respectively. Results also showed that ctDNA clearance was associated with improved outcomes in the atezolizumab group; moreover, ctDNA-positive patients with high tumor mutational burden (TMB) had improved outcomes versus those with TMB-low disease, as well as those with PD-L1 IC2/3 expression.

In our exclusive interview, Powles and Rini provide insight into this analysis of the IMvigor010 study and its implications for ctDNA as a biomarker in urothelial cancer and beyond.

To hear more from the Uromigos, listen to their podcast here.