The open label trial is being conducted by the NCIC Clinical Trials Group (NCIC CTG), Queen’s University in Kingston, Canada.
Oncothyreon president and CEO Robert Kirkman said the NCIC CTG extended support in PX-866, the novel, irreversible PI-3K inhibitor, with the expansion of the Phase 2 trial in prostate cancer.
"This trial is an important component of our broad Phase 2 program for PX-866, intended to provide significant information to guide later stage development of this product candidate," Kirkman added.
The Part A of the trial, which enrolled approximately 36 of a planned 40 patients with progressive castration-resistant prostate cancer who have received no prior chemotherapy, included an interim efficacy analysis after enrolment of the first 23 patients, which was met.
Part B will enrol patients who demonstrate disease progression while receiving abiraterone as evidenced by a rising prostate specific antigen (PSA) following the enrolment in Part A.
The proportion of patients with lack of disease progression at 12 weeks from the initiation of therapy with PX-866, is the primary endpoint of each part of the single-arm screening trial.