Oncternal Therapeutics Announced Pre-Clinical Data from ONCT-534, an Androgen Receptor N-Terminal-Domain-Binding Small Molecule Degrader, Was Accepted for Virtual Poster Presentation at AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics

Androgen Receptor (AR) inhibition is an important therapeutic approach for the treatment of Castration-Resistant Prostate Cancer (CRPC), but AR-escape mechanisms related to the expression of AR splice variants (AR-SV), such as AR-V7, represent a significant unmet need and are a key area of focus for novel therapies in developmentONCT-534 may become a promising next-generation treatment option for CRPC and for the clinically-important emerging class of AR-SV-expressing prostate cancers SAN DIEGO, Oct. 05, 2021 (GLOBE NEWSWIRE) — Oncternal Therapeutics, Inc. (Nasdaq: ONCT), a clinical-stage biopharmaceutical company focused on the development of novel oncology therapies, today announced pre-clinical data from ONCT-534, an androgen receptor N-terminal-domain-binding small molecule degrader, was accepted for virtual poster presentation at the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics on October 7-10, 2021. Oncternal has conducted a series of preclinical studies in collaboration with the Center for Cancer Research at the University of Tennessee Health Science Center. The ONCT-534 data will be presented as a late-breaking abstract selected for virtual poster presentations and will be available for on-demand viewing in the AACR-NCI-EORTC platform on October 7, 2021, at 9 a.m. ET. Abstract Title: Androgen Receptor (AR) N-Terminus-Domain-Binding Small Molecule Degraders for the Treatment of AR Splice Variant-Positive Castration-Resistant Prostate CancerAbstract Number: LBA016 “Despite relatively recent advances in treating CRPC, 5-year overall survival remains low, and patients are in need of more effective treatment options” said James Breitmeyer, M.D., Ph.D., Oncternal’s President and CEO. “In preclinical research, ONCT-534 has demonstrated anti-tumor activity in a series of studies and might have the potential to address significant unmet needs related to important tumor resistance mechanisms, including those involving expression of the AR splice variant AR-V7.” About ONCT-534 ONCT-534 (formerly GTx-534) is an investigational, potentially first-in-class androgen receptor (AR) N-terminal-domain-binding small molecule degrader, currently in preclinical development, that was originally discovered by the Center for Cancer Research at the University of Tennessee Health Science Center. Oncternal acquired rights to ONCT-534, which is part of what was previously known as the selective androgen receptor degrader (SARD) program, in Oncternal’s reverse merger with GTx, Inc. in 2019. ONCT-534 has demonstrated preclinical activity in prostate cancer tumor models resistant to approved AR-targeting therapies. Oncternal is currently evaluating strategic development options for ONCT-534 as a potential therapy for castration-resistant prostate cancer (CRPC), LAR-TNBC as well as AR-driven non-oncology indications.  Oncternal is currently seeking to amend the financial terms of a contingent value rights (CVR) agreement relating to the program, subject to approval of a majority in interest of the CVR holders. Among other things, the amendment would increase Oncternal’s share of proceeds from commercialization or other monetization of the program while limiting certain deductions in some cases to those costs incurred after the potential amendment becomes effective. Oncternal intends to provide a programmatic update on ONCT-534 on its earnings call planned for early November 2021. About Oncternal Therapeutics (Nasdaq: ONCT) Oncternal Therapeutics is a clinical-stage biopharmaceutical company focused on the development of novel oncology therapies for the treatment of cancers with critical unmet medical need. Oncternal focuses drug development on promising yet untapped biological pathways implicated in cancer generation or progression. The clinical pipeline includes cirmtuzumab, an investigational monoclonal antibody designed to inhibit the ROR1 pathway, a type I tyrosine kinase-like orphan receptor, that is being evaluated in a Phase 1/2 clinical trial in combination with ibrutinib for the treatment of patients with mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL) and in an investigator-sponsored, Phase 1b clinical trial in combination with paclitaxel for the treatment of women with HER2-negative metastatic or locally advanced, unresectable breast cancer, as well as a Phase 2 clinical trial of cirmtuzumab in combination with venetoclax, a Bcl-2 inhibitor, in patients with relapsed/refractory CLL. Oncternal is also developing a chimeric antigen receptor T cell (CAR-T) therapy that targets ROR1, which is currently in preclinical development as a potential treatment for hematologic cancers and solid tumors. The clinical pipeline also includes TK216, an investigational targeted small-molecule inhibitor of the ETS family of oncoproteins, that is being evaluated in a Phase 1/2 clinical trial for patients with Ewing sarcoma alone and in combination with vincristine chemotherapy. More information is available at https://oncternal.com. Oncternal’s Forward-Looking Information Oncternal cautions you that statements included in this press release that are not a description of historical facts are forward-looking statements. In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplates,” “believes,” “estimates,” “predicts,” “potential” or “continue” or the negatives of these terms or other similar expressions. These statements are based on Oncternal’s current beliefs and expectations. Forward-looking statements include statements regarding the potential of, and planned updates for, the ONCT-534 program. Forward-looking statements are subject to risks and uncertainties inherent in Oncternal’s business, including risks associated with the clinical development and process for obtaining regulatory approval of Oncternal’s product candidates, such as potential delays in the commencement, enrollment and completion of clinical trials; the risk that results seen in a case study of one patient likely will not predict the results seen in other patients in the clinical trial; the risk that interim results of a clinical trial do not predict final results and that one or more of the clinical outcomes may materially change as patient enrollment continues, following more comprehensive reviews of the data, as follow-up on the outcome of any particular patient continues, and as more patient data become available; the risk that Oncternal is unable to obtain approval to amend the contingent value rights agreement and may be unable to continue to develop ONCT-534 if the anticipated return on investment is not commercially reasonable; and other risks described in Oncternal’s filings with the U.S. Securities and Exchange Commission. All forward-looking statements in this press release are current only as of the date hereof and, except as required by applicable law, Oncternal undertakes no obligation to revise or update any forward-looking statement, or to make any other forward-looking statements, whether as a result of new information, future events or otherwise. All forward-looking statements are qualified in their entirety by this cautionary statement. This caution is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. For more information please contact: Oncternal Contacts: Investors:Richard [email protected] Media:Corey Davis, Ph.D.LifeSci [email protected]