17 Jul First Oral Cancer Vaccine Using Bacterial Vector Shows Safety and Immune Response in Metastatic Urothelial Cancer Phase I Trial
MedicalResearch.com Interview with:
Toshiro Shirakawa, MD, PhD
Dean and Professor
Graduate School of Science, Technology and Innovation, Kobe University
Prof. Shirakawa[/caption]
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Shirakawa: Immune checkpoint inhibitors have significantly improved the treatment of metastatic urothelial cancer, but many patients eventually develop resistance, leaving limited therapeutic options. We developed B440, a first-in-human oral cancer vaccine using genetically engineered Bifidobacterium longum expressing the WT1 tumor-associated antigen, with the goal of enhancing tumor-specific cellular immunity through the gut immune system.
In this phase I study, B440 demonstrated a favorable safety profile with no dose-limiting toxicities. WT1-specific cellular immune responses were detected in half of the patients, and these patients showed a trend toward longer progression-free survival. As this was a small, single-arm phase I study, these findings should be considered exploratory and hypothesis-generating. For context on how immune checkpoint inhibitors have reshaped the treatment landscape for metastatic urothelial cancer, see this earlier overview of immunotherapy in the treatment of metastatic urothelial cancer.