Oncolytics Biotech Receives FDA Fast Track For Pelareorep In Second-Line KRAS-Mutant MSS Metastatic Colorectal Cancer Following Strong Clinical Data

Oncolytics Biotech® Inc., a clinical-stage immunotherapy company developing pelareorep, announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation to pelareorep in combination with bevacizumab (Avastin®) and FOLFIRI (leucovorin, fluorouracil, irinotecan) for the treatment of patients with KRAS-mutant, microsatellite-stable (MSS) metastatic colorectal cancer (mCRC) in the second-line setting. This designation follows the company’s increased focus on gastrointestinal cancers and a review of its existing colorectal cancer dataset in the fall of 2025.

The Fast Track Designation is supported by clinical data showing a 33% objective response rate (ORR) for pelareorep combination therapy compared to approximately 10% with standard-of-care (SOC) in this patient population. In addition, median progression-free survival (PFS) was 16.6 months with pelareorep-based therapy versus 5.7 months with SOC, and median overall survival (OS) was 27 months compared to 11.2 months with SOC.

KRAS-mutant MSS mCRC represents a particularly difficult-to-treat form of colorectal cancer, as effective treatment options are limited following first-line therapy, and currently available immune-based therapies offer minimal benefit. Globally, colorectal cancer affects an estimated 2 million new patients each year, with the second-line KRAS-mutant MSS mCRC subgroup representing an annual total addressable market of approximately $3–5 billion.

Jared Kelly, Chief Executive Officer of Oncolytics, stated, “This designation is an important validation of our focus on pelareorep’s potential as a platform immunotherapy for gastrointestinal cancers, including colorectal cancer. Adding pelareorep to the standard-of-care in this underserved patient population significantly improves key clinical endpoints, including overall survival, progression-free survival, and objective response rate. This represents a meaningful opportunity to impact patients’ lives in a market estimated to be worth several billion dollars. We look forward to working closely with the FDA to address this critical treatment gap as quickly as possible.”

Oncolytics plans to initiate a controlled clinical study in second-line KRAS-mutant MSS mCRC, comparing standard-of-care therapy alone versus standard-of-care plus pelareorep. The first clinical site is expected to be activated in March, with up to 10 additional sites opening shortly thereafter. Interim data from the study are anticipated by year-end, with further details on study design and milestones to be provided in the coming months.

The Fast Track Designation allows for more frequent communication with the FDA to ensure alignment on development plans and the collection of clinical data necessary to support regulatory approval. Programs with Fast Track status may also be eligible for Accelerated Approval and Priority Review if relevant criteria are met. To receive Fast Track Designation, a therapy must demonstrate a potential advantage over existing treatments, such as improved efficacy or safety, for a condition where other options are available.