Oncolytics reports faster enrollment in REO 033 colorectal cancer study
Nearly all Part A sites are active, an interim update is expected by year-end 2026, and the FDA has aligned on a possible accelerated approval route.
Oncolytics Biotech Inc. (Nasdaq: ONCY) said on September 28, 2026 that nearly all planned clinical sites for Part A of REO 033 have now been activated, and multiple patients are currently enrolled.1 The company said with the site activation process largely complete, it is turning its attention to speeding up enrollment and producing randomized data on how pelareorep adds to the existing standard-of-care regimen.1
The study tests pelareorep combined with FOLFIRI (folinic acid, fluorouracil and irinotecan) plus bevacizumab against FOLFIRI and bevacizumab alone in patients with second-line RAS-mutant, microsatellite-stable metastatic colorectal cancer.1 Part A aims to enroll about 60 patients split between the two arms, with objective response rate as the primary endpoint and progression-free survival, overall survival, safety, and biomarker measures as additional endpoints.1
Chief Operating Officer John McAdory said the company expects to be able to report interim data from Part A by year-end, based on the number of evaluable patients enrolled by the end of October.1
The design builds on an earlier, non-randomized study, REO 022, in which pelareorep combined with FOLFIRI and bevacizumab showed an objective response rate of 33%, median progression-free survival of 16.6 months, and median overall survival of 27.0 months, versus historical second-line benchmarks of roughly 6-11% ORR, 5.7 months PFS, and 11.2 months OS.1 The company noted the REO 022 results came from a small, non-randomized study and that cross-study comparisons have inherent limitations.1
Oncolytics also said it recently reached alignment with the FDA on the concept of a potential pivotal Part B expansion of REO 033.1 Under that plan, Part B would extend directly from the ongoing randomized REO 033 study and could support a submission for accelerated approval based on objective response rate, with progression-free survival serving as the basis for full approval.1 The company said Part A data would help determine the final size and execution of the proposed Part B expansion.1
Written by readthrough’s AI from the linked primary sources and fact-checked against them automatically before publishing. Not investment advice.