Oncolytics Biotech Inc. (NASDAQ: ONCY) (TSX: ONC) is advancing its lead cancer therapy, pelareorep, towards potential accelerated approval, focusing on metastatic breast cancer and expanding its research in gastrointestinal cancers, particularly pancreatic cancer. The company's strategy is underpinned by promising clinical data and strategic collaborations aimed at addressing unmet needs in oncology. Recent data from the BRACELET-1 trial in HR+/HER2- breast cancer has paved the way for a pivotal clinical study designed to support accelerated approval. Key milestones in gastrointestinal cancer clinical trials are anticipated in 2025, potentially leading to new registration-enabling studies.
Accelerated Approval Pathway for Breast Cancer
The decision to pursue accelerated approval is rooted in the encouraging outcomes of the Phase 2 BRACELET-1 trial (NCT04215146) and constructive feedback from the U.S. Food and Drug Administration (FDA). Wayne Pisano, Interim CEO and Chair of Oncolytics’ Board of Directors, expressed enthusiasm about the BRACELET-1 results, stating they “exceeded our expectations and substantiate the strong efficacy signal previously observed in breast cancer patients treated with pelareorep.”
Oncolytics plans to submit a trial of pelareorep combined with paclitaxel to the FDA in early 2025. The Phase 2 study will enroll approximately 180 patients with HR+/HER2- advanced/metastatic breast cancer who have progressed on antibody-drug conjugates (ADCs) like Enhertu, are ineligible for ADCs, or cannot tolerate them. This patient population represents approximately 55,000 individuals in the U.S. The study design is statistically powered to demonstrate a p-value of < 0.05, with a progression-free survival (PFS) benefit of ≥4.3 months.
BRACELET-1 Trial Efficacy Data
Final results from the BRACELET-1 study demonstrated a median overall survival (OS) that was “Not Reached” for the pelareorep combination therapy arm, with over half the patients still alive at the time of the final survival analysis. A conservative estimate places the median OS at 32.1 months, indicating a greater than 12-month survival advantage compared to paclitaxel alone, which had a median OS of 18.2 months. The 24-month overall survival rate was 64% for the pelareorep arm versus 33% for the paclitaxel arm. The final progression-free survival (PFS) was 12.1 months for pelareorep plus paclitaxel, compared to 6.4 months for paclitaxel alone, a difference of 5.7 months.
Expanding into Gastrointestinal Cancers
Oncolytics is also focusing on gastrointestinal cancers, particularly pancreatic cancer. The company has established a collaboration with the Global Coalition for Adaptive Research (GCAR) and received funding from The Pancreatic Cancer Action Network (PanCAN) to further investigate pelareorep in pancreatic cancer through the GOBLET study. Initial efficacy results from cohort 5 of the GOBLET study, which is investigating pelareorep in combination with modified FOLFIRINOX (mFOLFIRINOX) with or without atezolizumab, are expected in the second half of 2025.
Anticipated Milestones
Key upcoming milestones for Oncolytics include:
- Initiating a registrational study of pelareorep + paclitaxel in HR+/HER2- metastatic breast cancer in H1 2025.
- Releasing safety run-in data from cohort 5 of the GOBLET study, investigating pelareorep and mFOLFIRINOX with or without atezolizumab in newly diagnosed pancreatic cancer in H1 2025.
- Providing updated efficacy data from cohort 4 of the GOBLET study, investigating pelareorep and atezolizumab in second-line or later anal cancer in H1 2025.
- Announcing initial efficacy results from cohort 5 of the GOBLET study in H2 2025.
Thomas Heineman, M.D., Ph.D., Chief Medical Officer at Oncolytics, emphasized the company's strategic approach, stating, “Based on the success of these studies, we are now ready to pursue a large phase 2 study powered to support an accelerated approval in the setting of ADC therapies such as Enhertu.”
