OncoGenex Pharmaceuticals, Inc. announced positive survival results from the final analysis of the phase 2 Borealis-2 trial of apatorsen in combination with docetaxel treatment that enrolled 200 patients with metastatic bladder cancer whose disease had progressed following first-line platinum-based chemotherapy. Patients who received apatorsen treatment experienced a 20% reduction in risk of death, compared to patients receiving docetaxel alone (HR=.80; 95% CI: 0.65-0.98; p=0.078). The primary analysis was a superiority test of overall survival, performed at a one-sided 0.10 significance level using a stratified log-rank test. The trial was conducted by the Hoosier Cancer Research Network at 28 sites across the United States.
Safety results in patients treated with apatorsen and docetaxel were similar to those observed in patients treated with docetaxel alone.
"People living with advanced bladder cancer who have failed initial therapies have few treatment options available to them. While research across different treatment modalities is underway, there continues to be a high unmet therapeutic need," said one of the principal investigators, Jonathan Rosenberg, MD of Memorial Sloan Kettering Cancer Center. "The totality of the data evaluating apatorsen across first- and second-line chemotherapy treatment for bladder cancer suggests that it may provide clinical benefits in this highly aggressive disease."
Apatorsen is designed to inhibit production of heat shock protein 27 (Hsp27) to disable cancer cells' defenses and overcome treatment resistance. Hsp27 is an intracellular protein that protects cancer cells by helping them survive, leading to resistance and more aggressive cancer phenotypes.
"We are encouraged by these data that further support Hsp27 as a therapeutic target and add an additional level of evidence to previously completed trials of apatorsen in patients with bladder cancer," said Scott Cormack, president and CEO of OncoGenex. "We look forward to completing the full data analysis from Borealis-2 and considering these data in our continuing work with MTS Health Partners in the exploration of strategic alternatives as announced in mid-August."
Borealis-2 is an investigator-sponsored, randomized phase 2 trial evaluating a survival benefit with apatorsen in combination with docetaxel treatment compared to docetaxel treatment alone in approximately 200 patients with metastatic bladder cancer who have disease progression following first-line platinum-based chemotherapy.