ESSA Pharma Presents Preclinical Data for its First Generation Androgen Receptor N-Terminal Domain Degrader at the 34th EORTC-NCI-AACR Symposium

ESSA Pharma Inc. (“ESSA”, or the “Company”) (NASDAQ: EPIX), a clinical-stage pharmaceutical company focused on developing novel therapies for the treatment of prostate cancer, announced the presentation of preclinical data for its lead first generation androgen receptor (“AR”) ANITen bAsed Chimera (“ANITAC”™) N-terminal domain (“NTD”) degrader in a poster session at the 34^th EORTC-NCI-AACR Annual Symposium on Molecular Targets and Cancer Therapeutics in Barcelona, Spain.

The preclinical data demonstrate that EPI-8207, an ANITAC, shows robust potency degrading AR, including AR splice variants and clinically relevant AR mutants that can potentially drive disease progression in patients with castration-resistant prostate cancer (“CRPC”). In addition, EPI-8207 exhibits high potency in inhibiting AR-dependent transcription.

Presentation Details

34^th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics

Title: Advances in the Development of a Targeted N-Terminal Domain Androgen Receptor Degrader (ANITAC) for the Treatment of Prostate Cancer
Authors: Nan Hyung Hong, et al.
Abstract Number: 103
Session Title: New Drugs

The poster is available on the EORTC-NCI-AACR Annual Symposium website at www.eortc.org/ena and on the “Publications” section of the Company’s website at www.essapharma.com.

About ANITAC™ Degraders

Androgen receptor signaling is the main driver of prostate cancer progression and remains a crucial target for therapeutic intervention in late stages of the disease. While current antiandrogen therapies that directly or indirectly target the AR ligand-binding domain (LBD) are initially effective, resistance ultimately develops and new methods of inhibiting the AR pathway are needed.

ESSA’s novel approach of targeting the N-terminal domain of the AR represents a new method of blocking AR signaling. Leveraging ESSA’s scientific foundation in successfully targeting the NTD of the AR with a new class of small molecules called anitens, ESSA is developing the first generation of ANITen bAsed Chimera degraders targeting the AR NTD. In preclinical models, the orally bioavailable ANITAC degraders can eliminate forms of AR protein found in castration-resistant prostate cancer that can potentially drive disease progression including LBD mutants and LBD truncated splice variants.

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, 2018). 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, disease progression despite castrate levels of testosterone can lead to metastatic CRPC (“mCRPC”). The treatment of mCRPC patients has evolved rapidly over the past ten years. Despite these advances, many patients with mCRPC fail or develop resistance to existing treatments, leading to continued disease progression and limited survival rates.

About ESSA Pharma Inc.

ESSA is a clinical-stage pharmaceutical company focused on developing novel and proprietary therapies for the treatment of patients with prostate cancer. For more information, please visit www.essapharma.com and follow us on Twitter under @ESSAPharma.