ESSA Pharma has signed a clinical trial support agreement with Janssen Research & Development to evaluate its EPI-7386 combinations for the treatment of men with prostate cancer.

As per the agreement, Janssen will supply ESSA with apalutamide and abiraterone acetate for a Phase I clinical trial which will be sponsored and conducted by the latter.

The trial will evaluate the safety, pharmacokinetics, drug-drug interactions, and preliminary anti-tumour activity of EPI-7386 when administered in combination with either apalutamide or abiraterone acetate plus prednisone.

Patients with metastatic castration-resistant prostate cancer (mCRPC) and high-risk metastatic castration-sensitive prostate cancer (mCSPC) will receive EPI-7386 along with abiraterone acetate plus prednisone in Cohort A of the Phase I trial.

In Cohort B, a window of opportunity study, non-metastatic CRPC patients will be dosed with single agent EPI-7386 before adding standard-of-care apalutamide for up to 12 weeks.

ESSA president and CEO David 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 favorable 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.”

Across the globe, ESSA will retain all rights to the oral, small molecule inhibitor of the N-terminal domain of the androgen receptor, EPI-7386.

The company is also evaluating EPI-7386 in combination with enzalutamide in a Phase I/II trial in metastatic CRPC patients who are yet to receive treatment with second-generation antiandrogen therapies.