REOLYSIN MORE THAN DOUBLES OVERALL SURVIVAL IN PATIENTS WITH MUTATED P53 METASTATIC BREAST CANCER
Oncolytics Biotech Inc. (ONC.T) has released data demonstrating a statistically significant (p equals 0.03) overall survival (OS) benefit for patients with mutated p53 metastatic breast cancer, when treated with Reolysin, an immuno-oncology viral agent, in combination with paclitaxel. Results from IND 213, an open-label, randomized, phase 2 study were presented at the annual meeting of the American Association of Cancer Research (AACR), April 1 to April 5, 2017, in Washington.
"Mutations of the p53 tumour suppressor gene play an increasingly challenging role throughout the life cycle of cancer," said Dr. Matt Coffey, president and chief executive officer of Oncolytics. "As breast cancer progresses clinically, p53 mutations become more prominent and negatively impact therapeutic efficacy and overall survival. These data provide evidence that combining Reolysin with paclitaxel may improve survival for this difficult-to-treat, well-characterized, patient population."
The open-label, randomized, phase 2 study enrolled 74 patients with metastatic breast cancer, 82 per cent (61 patients) of whom presented with p53 mutated tumours. The results show patients with mutated p53 metastatic breast cancer that were treated with Reolysin in combination with paclitaxel (n equals 30) had a median OS of 20.9 months versus 10.4 months (n equals 31) in patients treated only with paclitaxel. The study was designed and conducted by the Canadian Cancer Trials Group (CCTG, formerly known as the National Cancer Institute of Canada -- NCIC).
"The observed survival benefit is very exciting and reinforces the effectiveness and tolerability of Reolysin in patients with mutated p53 metastatic breast cancer, while demonstrating its potential utility in earlier lines of treatment for this difficult-to-treat, high-risk group of patients," said Dr. Andres Gutierrez, chief medical officer of Oncolytics. "These data indicate overall survival is more than doubled for patients when treatment with Reolysin is added to the standard of care and highlight key considerations for the design and execution of a registration study in breast cancer. Our immediate next steps include seeking advice from key opinion leaders and regulators on refining our go-forward regulatory strategy and registration pathway."
In the abstract for the poster, the CCTG had previously reported that in the intention-to-treat patient population there was an improvement in median OS (secondary endpoint) from 10.4 months on the control arm to 17.4 months on the test arm (hazard ratio 0.65, 80 per cent CI 0.46 to 0.91, p equals 0.1) meeting the prespecified significance threshold with powering of 90 per cent. Consistent with Reolysin acting as an immune therapy agent, there was no meaningful improvement in either progression free survival (the primary end point), or response rate (secondary end point). With this overall survival data and the additional data from the p53 patient group, the company has commenced the planning of a registration study in metastatic breast cancer with overall survival as the primary end point.
The poster, authored by Bernstein et al., "A randomized (RCT) phase 2 study of oncolytic reovirus (pelareorep) plus standard weekly paclitaxel (P) as therapy for metastatic breast cancer (mBC)," will be available on the Oncolytics website.
About breast cancer
The National Cancer Institute reported 246,660 new cases of breast cancer diagnosed in the United States and 40,450 deaths from the disease in 2016.
About Oncolytics Biotech Inc.
Oncolytics is a biotechnology company developing Reolysin, an immuno-oncology viral agent, as a potential treatment for a variety of tumour types. The compound induces selective tumour lysis and promotes an inflamed tumour phenotype through innate and adaptive immune responses to treat a variety of cancers. Oncolytics's clinical development program emphasizes three pillars: chemotherapy combinations to trigger selective tumour lysis, immunotherapy combinations to produce adaptive immune responses and immune modulator (IMiD) combinations to facilitate innate immune responses. Oncolytics is currently planning its first registration study in breast cancer as well as studies in combination with checkpoint inhibitors and IMID/targeted therapies in solid and hematological malignancies.