Dr. Chi on the Prostate Cancer Biomarker Enrichment and Treatment Selection Study

Kim Chi, MD, senior research scientist, Vancouver Prostate Centre, chief medical officer and vice president, BC Cancer, medical oncologist, BC Cancer, professor, Department of Medicine, University of British Columbia, discusses prostate cancer biomarker enrichment and treatment selection study.

A multitude of therapy options are available for men with castration-resistant prostate cancer (mCRPC) but the disease remains lethal, says Chi. However, genomic characterization of mCRPC has identified frequently occurring, actionable alterations that could potentially be targeted with novel treatments.

To efficiently evaluate the antitumor activity of novel targeted therapies, Chi and colleagues initiated an ongoing phase 2 umbrella trial in which patients with mCRPC were enrolled and stratified in accordance to biomarker status. Notably, each patient had circulating tumor DNA sequencing and identification of actionable alterations.

Patients who were biomarker positive were enrolled by a tumor board using preset criteria to various treatment arms of targeted therapies, while those who were biomarker negative were randomized to any of the open arms. A preliminary analysis of the study demonstrated feasibility for this approach. Over 250 patients have been screened thus far, over a span of 29 months. Early activity has been observed in patients who received treatment with adavosertib (AZD 1775) and darolutamide (Nubeqa), ultimately meeting the threshold for expansion of these arms, Chi concludes.