Dr. Tyson discusses phase 3 trial of oncolytic immunotherapy in NMIBC

In this video, Mark D. Tyson, MD, MPH, highlights the background and notable findings from the phase 3 BOND-003 trial (NCT04452591) exploring cretostimogene grenadenorepvec in patients with BCG-unresponsive non-muscle-invasive bladder cancer. The data were presented at the 2023 Society of Urologic Oncology Annual Meeting in Washington DC. Tyson is a urologic oncologist at the Mayo Clinic in Phoenix, Arizona.

Video Transcript:

Could you describe the background for the BOND-003 trial?

BOND-003 is a single-arm, open-label, phase 3 registrational study, evaluating cretostimogene grenadenorepvec monotherapy for patients with BCG-unresponsive non-muscle-invasive bladder cancer. The population under study is a BCG-unresponsive CIS population, according to the strict definition provided by the FDA in their 2018 guidance. We did allow papillary disease in this study, but they had to be completely resected prior to study entry. We required mandatory biopsies at 12 months, which included a few different regions in the bladder, 5 regions of the bladder, as well as the prosthetic urethra. In terms of treatments, patients underwent 6 sequential weekly installations of cretostimogene, followed by maintenance therapy for responders up to 18 months, and repeat induction for non-responders. The primary end point was complete response at any time point. Secondary end points were complete response at 12 months, progression-free, recurrence-free, and cystectomy-free survival.

What were the notable findings from this study?

The primary end point was impressive. The efficacy analysis for all patients based upon a central pathology review revealed a complete response at any time point of 75.7%. If you look at the confidence interval for that, the range of plausible CRs were between 63% and 85%. That's a really impressive complete response rate for a monotherapy agent. Now, obviously, it's an interim result. We're going to wait to see what the final numbers show, but that's the first and foremost finding that I would highlight. Secondly, in terms of durability of response, we did see that of those who had a response, 74.4% of them responded beyond 6 months. That's also pretty impressive. In terms of toxicity, we didn't see any grade 3 treatment-related adverse events. We did not see any deaths. We didn't see any treatment discontinuations due to adverse events. We saw 2 grade 2 serious adverse events. I would say those are the 3 main highlights.

This transcription has been edited for clarity.