HOUSTON, TX, USA and VANCOUVER, Canada I November 24, 2015 I ESSA Pharma Inc. (“ESSA” or the “Company”) (TSX: EPI; NASDAQ: EPIX) announced today that the first patient has been enrolled in ESSA’s Phase 1/2 clinical study of EPI-506 as a treatment for metastatic castration-resistant prostate cancer (“mCRPC”).

In the Phase 1/2 clinical trial, ESSA intends to demonstrate the safety, tolerability, maximum tolerated-dose, pharmacokinetics, and efficacy of EPI-506 in prostate cancer patients who have failed abiraterone or enzalutamide or both, the current standard-of-care drugs in mCRPC.  The trial is expected to enroll approximately 150 subjects across the United States and Canada. 

“Patients with metastatic CRPC who have failed abiraterone and/or enzalutamide currently represent a large unmet medical need,” said Dr. Frank Perabo, ESSA’s Chief Medical Officer. “The novel mechanism of action of EPI-506 was developed specifically to overcome resistance to these current drugs.”

As part of the clinical study, ESSA will collect molecular biomarker information which may provide useful context in understanding patient outcomes.  Androgen receptor splice variant V7 data will be included in such information.

Details relating to the Phase 1/2 clinical trial are now available on the US National Institutes of Health clinical trials website (https://clinicaltrials.gov).

About ESSA Pharma Inc.

ESSA Pharma is a clinical-stage pharmaceutical company focused on developing novel and proprietary therapies for the treatment of castration resistant prostate cancer (“CRPC”) in patients whose disease is progressing despite treatment with current therapies. ESSA believes that its product candidate, EPI-506, can significantly expand the interval of time in which patients suffering from CRPC can benefit from hormone-based therapies. EPI-506 acts by disrupting the androgen receptor (“AR”) signaling pathway, which is the primary pathway that drives prostate cancer growth. We have shown that EPI-002, the primary metabolite of EPI-506, prevents AR activation by binding selectively to the N-terminal domain (“NTD”) of the AR. A functional NTD is essential for activation of the AR. Blocking the NTD prevents activation of the AR by all of the three known mechanisms of activation. In pre-clinical studies, blocking the NTD has demonstrated the capability to overcome the known AR-dependent mechanisms of CRPC. ESSA was founded in 2009 and is located in Vancouver, British Columbia and Houston Texas.

About Prostate Cancer

Prostate cancer is the second-most commonly diagnosed cancer among men and the fifth most common cause of male cancer death worldwide (Globocan, 2012). Adenocarcinoma of the prostate is dependent on androgen for tumor progression and depleting or blocking androgen action has been a mainstay of hormonal treatment for over six decades. Although tumors are often initially sensitive to medical or surgical therapies that decrease levels of testosterone (for example, ADT), disease progression despite castrate levels of testosterone generally represents a transition to the lethal variant of the disease (mCRPC) and most patients ultimately succumb to the illness. The treatment of mCRPC patients has evolved rapidly over the past five years; despite these advances, additional treatment options are needed to improve clinical outcomes in patients, particularly those who fail existing treatments including abiraterone or enzalutamide, or those that have contraindications to receive those drugs. Over time, patients with mCRPC generally experience continued disease progression, worsening pain, leading to substantial morbidity and limited survival rates. In both in vitro and in vivo studies, ESSA’s novel approach to blocking the androgen pathway has been shown to be effective in blocking tumor growth when current therapies are no longer effective.

SOURCE: ESSA Pharma