Oncolytics Biotech Reports FDA Milestone and Strong Clinical Progress in RAS-Mutant MSS Colorectal Cancer Trial
Half of the planned clinical sites are expected to be activated this month, with more than 20 patients already pre-identified across participating centers
Company to hold a Type D meeting with the FDA to discuss a potential registrational pathway through the addition of Part B to the existing REO 033 trial
SAN DIEGO, July 13, 2026 (GLOBE NEWSWIRE) -- Oncolytics Biotech® Inc. (NASDAQ: ONCY) (“Oncolytics” or the “Company”), a clinical-stage biotechnology company developing pelareorep, today provided a clinical and regulatory update on REO 033, its randomized controlled study in patients with RAS-mutant, microsatellite stable (“MSS”) metastatic colorectal cancer.
Pelareorep is an investigational, systemically active immunotherapy designed to promote potentially protective immune responses. Its effects include the upregulation of key inflammatory cytokines, the formation of tertiary lymphoid structures, and the expansion of tumor-infiltrating lymphocytes.
REO 033 is evaluating pelareorep in combination with folinic acid, fluorouracil and irinotecan (“FOLFIRI”) and bevacizumab as a second-line treatment for patients with RAS-mutant MSS metastatic colorectal cancer.
Building on Encouraging REO 022 Results
REO 033 builds upon results previously reported from the REO 022 study, which more than doubled historical standard-of-care benchmarks across several important measures, including:
- Progression-free survival
- Overall survival
- Duration of response
- Objective response rate
Based on these results, pelareorep received Fast Track designation from the U.S. Food and Drug Administration (“FDA”) for this indication.
The multi-part randomized REO 033 study is designed to prospectively validate the encouraging REO 022 findings against a contemporary control arm while advancing pelareorep toward a potential registration pathway.
Clinical Sites Activating and Patients Identified
Oncolytics continues to make rapid operational progress in Part A of REO 033, which is expected to enroll approximately 60 patients.
Approximately half of the planned clinical sites are expected to be activated by the end of July 2026. More than 20 potential patients have already been pre-identified across participating centers.
The remaining clinical sites are expected to be activated by the end of August, positioning the trial for accelerated enrollment during the second half of 2026.
Most recently, global lead principal investigator Dr. Sanjay Goel and his team opened enrollment at the Rutgers Cancer Institute of New Jersey.
“The magnitude and durability of the efficacy observed in REO 022 warrant earnest evaluation in a randomized setting,” said Dr. Sanjay Goel, Global Lead Principal Investigator for REO 033 and Professor of Medicine and Director of the Phase I Program at Rutgers Cancer Institute of New Jersey. “It is encouraging to see REO 033 expanding rapidly across leading academic centers, and I believe this study has the potential to further define the role of pelareorep in RAS-mutant MSS metastatic colorectal cancer.”
FDA Type D Meeting Planned for August
Oncolytics also announced that it expects to hold a Type D meeting with the FDA during the first half of August 2026.
The meeting will focus on the proposed registrational design for REO 033 through the addition of Part B to the study.
Building on the currently enrolling Part A, the proposed registration-directed Part B would preserve the core design elements of REO 033 while:
- Increasing patient enrollment
- Incorporating a blinded independent central review
- Supporting a potential accelerated approval pathway
- Supporting a potential traditional full approval pathway
The Company intends to align with the FDA on a registrational pathway that preserves the operational efficiencies already established through REO 033 while maintaining continuity with the existing clinical program under a prospectively agreed regulatory framework.
“Launching a global randomized study with multiple high-quality sites in a short period of time reflects the operational capabilities of our clinical organization and our investigators,” said Jared Kelly, Chief Executive Officer of Oncolytics. “Just as importantly, our ongoing interactions with the FDA have enabled us to focus on efficiently transitioning REO 033 into a registration-directed program built upon the existing trial infrastructure.”
“We believe this strategy has the potential to significantly reduce development timelines while maintaining scientific rigor as we work to bring a much-needed immunotherapeutic option to patients in a treatment landscape that desperately needs innovation,” Kelly continued.
Potential Registration Pathway Without a Separate Trial
Oncolytics believes the proposed approach could allow the Company to generate early randomized efficacy data from Part A while simultaneously positioning Part B as a potential registrational study.
This strategy may eliminate the need to initiate an entirely separate registration trial.
The Company currently expects to:
- Report an initial tumor-response update from patients enrolled in Part A by the end of 2026
- Receive FDA feedback regarding the proposed registration-directed trial design
- Begin enrolling patients in Part B during the first quarter of 2027, subject to FDA feedback
About REO 033
REO 033 is a multi-part randomized controlled clinical trial evaluating pelareorep in combination with FOLFIRI and bevacizumab versus FOLFIRI and bevacizumab alone.
The trial is enrolling patients receiving second-line treatment for RAS-mutant, microsatellite stable metastatic colorectal cancer.
The study is designed to confirm the encouraging efficacy signals observed in REO 022 while generating the controlled clinical data needed to support future regulatory interactions and a potential registration pathway.
About Oncolytics Biotech Inc.
Oncolytics Biotech Inc. (NASDAQ: ONCY) is a clinical-stage biotechnology company developing pelareorep, an investigational, intravenously delivered double-stranded RNA immunotherapeutic agent.
Pelareorep is designed to induce anti-cancer immune responses by converting immunologically “cold” tumors into “hot” tumors through the activation of innate and adaptive immune responses.
Pelareorep has demonstrated encouraging results in:
- Multiple first-line pancreatic cancer studies
- Two randomized Phase 2 metastatic breast cancer studies
- Early-phase anal cancer studies
- Early-phase colorectal cancer studies
Oncolytics is advancing pelareorep in combination with chemotherapy and checkpoint inhibitors in metastatic gastrointestinal cancers.
Pelareorep has received FDA Fast Track designation for both colorectal cancer and pancreatic cancer. The Company is also actively pursuing strategic partnerships to accelerate development and maximize the potential commercial impact of pelareorep.
For additional information, visit www.oncolyticsbiotech.com or follow the Company on LinkedIn and X at @oncolytics.
References
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Goel, S., et al. “Elucidation of Pelareorep Pharmacodynamics in a Phase I Trial in Patients with KRAS-Mutated Colorectal Cancer.” Molecular Cancer Therapeutics, May 2020, 19(5), 1148-1156. doi: 10.1158/1535-7163.MCT-19-1117.
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U.S. Food and Drug Administration. “FDA Grants Accelerated Approval to Adagrasib with Cetuximab for KRAS G12C-Mutated Colorectal Cancer.” Published June 21, 2024. Accessed April 28, 2026.
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Bennouna, J. The Lancet Oncology, 2013, 14, 29-37.
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Iwamoto, S. Annals of Oncology, July 2015, 26(7), 1427-1433.
Forward-Looking Statements
This press release contains forward-looking statements within the meaning of Section 21E of the U.S. Securities Exchange Act of 1934, as amended, and forward-looking information under applicable Canadian securities laws. These statements are collectively referred to as “forward-looking statements.”
Forward-looking statements contained in this press release include statements regarding the potential registration, mechanism of action, clinical benefits, and therapeutic potential of pelareorep; the Company’s goals, strategies, and objectives; the design, milestones, timelines, and anticipated outcomes of current and future clinical studies; the clinical promise of pelareorep in colorectal, pancreatic, anal, and other gastrointestinal cancers; the expansion and progress of REO 033; clinical-site activation; patient enrollment; regulatory interactions; and future disclosure of clinical-trial results.
When Oncolytics expresses an expectation or belief regarding future results, those expectations or beliefs are expressed in good faith and are believed to have a reasonable basis. However, there can be no assurance that such expectations or beliefs will be achieved.
Forward-looking statements involve known and unknown risks and uncertainties that may cause actual results to differ materially from those anticipated. These risks include, but are not limited to, regulatory outcomes, clinical-trial execution, financial resources, access to capital markets, and changing market conditions.
Additional information regarding these risks is available in the Company’s public filings with securities regulators in the United States and Canada. Oncolytics assumes no obligation to update forward-looking statements except as required by applicable law.
Company Contact
Jon Patton
Director of Investor Relations & Communication
Email: jpatton@oncolytics.com