Zenith Epigenetics and Newsoara Announce Initiation of a Randomized Phase 2b Metastatic Castration-Resistant Prostate Cancer (mCRPC) Study

Evaluating the Combination of ZEN-3694 and Enzalutamide in mCRPC Patients Who Responded Poorly to Prior Abiraterone Treatment

CALGARY, Alberta, Sept. 21, 2021 (GLOBE NEWSWIRE) — Zenith Epigenetics Ltd. (“Zenith” or the “Company”) and Newsoara BioPharma Co., Ltd. (“Newsoara”) announced today the initiation of a multi-national, randomized Phase 2b clinical trial testing the combination of ZEN-3694, a leading BET bromodomain inhibitor (BETi), with Astellas Pharma Inc. (“Astellas”) and Pfizer’s androgen receptor signaling inhibitor (ARSI), enzalutamide, in patients with mCRPC who had a poor response to prior abiraterone treatment. The study will evaluate the efficacy of ZEN-3694 + enzalutamide vs. single agent enzalutamide as measured by its primary endpoint, radiographic free progression.

Abiraterone, also an ARSI, is frequently prescribed as a first line therapy for patients with metastatic prostate cancer. A significant fraction of these patients, whose tumors have low androgen receptor (AR) signaling activity, have a sub optimal response to abiraterone and their subsequent treatment options are limited to cytotoxic therapies. The rationale for this study design is supported by a recent publication in Clinical Cancer Research whose authors uncovered a potential mechanism explaining the role of BETi in sensitizing tumors with low AR signaling to ARSI by blocking a treatment-emergent neuroendocrine differentiation program. This mechanistic study built on a previous clinical trial conducted by Zenith where results suggested that ZEN-3694 + enzalutamide was most active in mCRPC patient tumors who had the lowest AR activity. Furthermore, patients in that trial that had a poor response to prior abiraterone therapy had the most durable response with ZEN-3694 + enzalutamide.

“We are delighted to initiate this study in collaboration with our partners Newsoara and Astellas to continue the development of ZEN-3694 in mCRPC patients,” said Donald McCaffrey, President and Chief Executive Officer of Zenith. “We are pursuing a novel approach of treating mCRPC patients whose tumors are resistant to ARSI. Other therapies, either approved or in development, are either cytotoxic or mainly target AR signaling which resistant tumors are no longer dependent on,” Mr. McCaffrey further commented.

Dr. Benny Li, Chief Executive Officer of Newsoara added, “with promising data from the completed Phase 1b/2a trial, the initiation of the multi-national, randomized Phase 2b clinical study in patients with mCRPC is a significant milestone for us to pursue a novel treatment through our partnership with Zenith.”

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. Adenocarcinoma of the prostate is dependent on androgen for tumor progression and depleting or blocking androgen action has been a mainstay for over six decades. Although tumors are often initially sensitive to medical or surgical therapies that decrease levels of testosterone and to ARSIs that block AR signaling, disease progression ultimately occurs leading to mCRPC. The treatment of prostate cancer patients has evolved rapidly over the past ten years with second generation ARSIs. Despite these advances, many patients with mCRPC fail or develop resistance to existing treatments, leading to continued disease progression and limited survival rates.

About Astellas

Astellas Pharma Inc. (“Astellas”) is a pharmaceutical company conducting business in more than 70 countries around the world. Astellas promotes the Focus Area Approach that is designed to identify opportunities for the continuous creation of new drugs to address diseases with high unmet medical needs by focusing on Biology and Modality. Furthermore, Astellas looks beyond its foundational Rx focus to create Rx+® healthcare solutions that combine its expertise and knowledge with cutting-edge technology in different fields of external partners. Through these efforts, Astellas stands on the forefront of healthcare change to turn innovative science into value for patients. For more information, please visit: https://www.astellas.com/en.

About Newsoara

Newsoara is a biotech company based in Shanghai, China with research laboratories in the Suzhou BioBAY focusing on novel drug research and development to address unmet medical needs in patients with oncology, autoimmune, respiratory, and metabolic diseases. Newsoara has licensed development and commercialization rights to ZEN-3694 for China, Hong Kong, Taiwan and Macau.

About Zenith

Zenith Capital Corp. is a biotechnology investment company originally spun out of Resverlogix Corp. (TSX: RVX) in 2013. Zenith Epigenetics Ltd., a wholly-owned subsidiary of Zenith Capital Corp., is a clinical stage biotechnology company focused on the discovery and development of novel therapeutics for the treatment of cancer and other disorders with significant unmet medical need. Zenith Epigenetics is developing various novel combinations of BET inhibitors with other targeted agents. The lead compound, ZEN-3694, is in clinical development for:

1. mCRPC in combination with androgen receptor inhibitor, enzalutamide (XTANDI), with Astellas and Newsoara as collaborators.
2. Triple Negative Breast Cancer in combination with the PARP inhibitor TALZENNA with Pfizer as a collaborator.
3. Androgen receptor independent mCRPC in combination with immune checkpoint inhibitor KEYTRUDA and XTANDI with University of California, San Francisco as a collaborator.
4. Ovarian cancer in combination with immune-checkpoint inhibitors, nivolumab and ipilimumab in collaboration with the National Cancer Institute.
5. Nut midline carcinoma in combination with chemotherapy in collaboration with the National Cancer Institute.

For further information, please contact:

Investor Relations & Communications
Zenith Epigenetics
Phone: 587-390-7865
Email: info@zenithepigenetics.com
Website: www.zenithepigenetics.com

This news release may contain certain forward-looking information as defined under applicable Canadian securities legislation, that are not based on historical fact, including without limitation statements containing the words “believes”, “anticipates”, “plans”, “intends”, “will”, “should”, “expects”, “continue”, “estimate”, “forecasts” and other similar expressions. In particular, this news release includes forward-looking information relating to the potential role of ZEN-3694 in the treatment of cancer and other disorders, and the Company’s development of ZEN-3694 including its planned Phase 2b Randomized Metastatic Castration-Resistant Prostate Cancer (mCRPC) study. Our actual results, events or developments could be materially different from those expressed or implied by these forward-looking statements. We can give no assurance that any of the events or expectations will occur or be realized. By their nature, forward-looking statements are subject to numerous assumptions and risk factors including those discussed in our most recent MD&A which are incorporated herein by reference and are available through SEDAR at www.sedar.com. The forward-looking statements contained in this news release are expressly qualified by this cautionary statement and are made as of the date hereof. Zenith disclaims any intention and has no obligation or responsibility, except as required by law, to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.