As part of the clinical trial support agreement, ESSA will sponsor and conduct a Phase 1 trial of EPI-7386, its experimental N-terminal domain androgen receptor inhibitor, in combination with apalutamide or abiraterone acetate plus prednisone


ESSA, Janssen to evaluate prostate cancer therapies. (Credit: Tatiana from Pixabay)

Canada-based ESSA Pharma has teamed up with US-based Janssen Research & Development to evaluate its EPI-7386 in combination with Janssen’s cancer therapeutics in patients with prostate cancer.

Under the clinical trial support agreement, ESSA will sponsor and conduct a Phase 1 trial of EPI-7386, in combination with Janssen’s apalutamide, and abiraterone acetate plus prednisone.

The Phase 1 clinical study will evaluate the safety, pharmacokinetics, drug-drug interactions, and preliminary anti-tumour activity of EPI-7386 combinations in treating prostate cancer.

The Canada-based pharmaceutical company will retain all rights to the investigational drug.

ESSA president and chief executive officer David R Parkinson said: “We are pleased to have this agreement in place in order to further investigate EPI-7386 in combination with apalutamide and abiraterone acetate plus prednisone in a variety of prostate cancer patient populations.

“Preliminary clinical data from EPI-7386 combination studies with standard-of-care antiandrogens in mCRPC patients have shown a favourable safety profile and encouraging early signs of anti-tumour activity.

“We look forward to examining EPI-7386 with apalutamide and abiraterone acetate with prednisone in additional prostate cancer populations to assess the safety, tolerability, optimal dose(s) and preliminary anti-tumour activities of these approaches.”

The Cohort A of the Phase 1 study will evaluate EPI-7386 in combination with abiraterone acetate plus prednisone in patients with metastatic castration-resistant prostate cancer (mCRPC) and high-risk metastatic castration-sensitive prostate cancer (mCSPC).

Cohort B will be conducted as a window of opportunity study, in which patients with non-metastatic CRPC will receive single agent EPI-7386 for up to 12 weeks, and apalutamide will be added as standard-of-care.

EPI-7386 is an experimental, highly selective, oral, small molecule that works to inhibit the activity of the N-terminal domain of the androgen receptor.

The drug is currently being studied in a Phase 1 clinical trial in men with castration-resistant prostate cancer (CRPC), whose tumours have progressed on standard-of-care therapies.

It has received the US FDA Fast Track designation for the treatment of adult male patients with mCRPC resistant to standard-of-care treatment.

ESSA is also conducting a Phase 1/2 study of EPI-7386 plus enzalutamide in metastatic CRPC patients who have not yet been treated with second-generation antiandrogen therapies.