Prelude Announces Multiple Clinical and Preclinical Poster Presentations at AACR-NCI-EORTC International Conference 

WILMINGTON, Del. and BOSTON, Oct. 14, 2023 (GLOBE NEWSWIRE) -- Prelude Therapeutics Incorporated (“Prelude”) (Nasdaq: PRLD), a clinical-stage precision oncology company, announces multiple clinical and preclinical posters at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, known as the Triple Meeting, from October 11 - 15, 2023 at the Hynes Convesntion Center in Boston, MA. The four Prelude poster presentations include data from two ongoing Phase 1 clinical trials for Prelude’s CDK9 inhibitor, PRT2527, and CDK4/6 inhibitor, PRT3645, and two preclinical posters for our SMARCA2 degrader compound, PRT3789.

“This additional data from our solid tumor trial investigating our potent and selective CDK9 inhibitor, PRT2527, continues to support a best-in-class safety and target engagement profile for the molecule. A second Phase 1 clinical trial in patients with hematological cancers is also underway, with initial data expected in 1H 2024,” stated Jane Huang, MD, President and Chief Medical Officer, Prelude Therapeutics.

Dr. Huang added, “We also presented our initial clinical data with our differentiated brain and tissue penetrant next generation CDK4/6 inhibitor, PRT3645, demonstrating a generally well-tolerated safety profile and high target inhibition reaching levels needed for efficacy in preclinical studies.”

Clinical Poster Presentations:

Title: A Phase 1 Dose-Escalation Study of PRT2527, a Cyclin-Dependent Kinase 9 (CDK9) Inhibitor, in Adult Patients with Advanced Solid Tumors: An Updated Analysis

Summary:

• The overall safety profile observed in this study supports further development of PRT2527 in combination with other targeted therapies in hematological malignancies.
  

Title: A Phase 1 Open-Label, Dose-Escalation Study of Central Nervous System–Penetrant Cyclin-Dependent Kinase (CDK)4/6 Inhibitor PRT3645 in Patients with Select Advanced or Metastatic Solid Tumors

Summary

• Initial clinical data from first three dose escalation cohorts (20, 40 and 80 mg QD) were reported.
• Treatment with PRT3645 was associated with a substantial decrease in pRb and Ki67 expression, indicating a high level of target engagement at the doses evaluated.
• PRT3645 exhibited tolerable dose escalation in the initial three dose cohorts of patients with no significant gastrointestinal, hematologic or neurological events reported to date, leveraging its enhanced selectivity profile.
  

Preclinical Poster Presentations:

“In addition to the preclinical efficacy we have seen with our potent and selective SMARCA2 degrader, PRT3789, as monotherapy, we see added potential in combination with immunotherapies as well as with chemotherapy and targeted therapies, such as KRAS inhibitors. The sensitive and quantitative assays we have developed to measure SMARCA2 degradation in preclinical models will also enable us to assess target engagement in the clinic. We look forward to the translation of these preclinical results in clinical readouts planned for 2024,” said Peggy Sherle, Ph.D., Chief Scientific Officer of Prelude Therapeutics.

Title: Discovery of PRT3789, a First-in-Class Potent and Selective SMARCA2 Degrader in Clinical Trials for the Treatment of Patients with SMARCA4 Mutated Cancers

Summary:

• PRT3789 is a potent and highly selective SMARCA2 protein degrader that specifically targets SMARCA4-deficient cancer cells.
• In preclinical models, PRT3789 inhibits the growth of SMARCA4-deficient NSCLC tumors as monotherapy and is synergistic in combination with other SOC therapies including chemotherapeutic agents, KRAS G12C inhibitors and anti-PD1 mAb.

Title: Clinical Biomarkers Based on PK/PD Modeling to Guide the Development for a First-in-Class, Highly Selective SMARCA2 (BRM) Degrader, PRT3789

Summary:

• Sensitive and quantitative assays to determine SMARCA2 and SMARCA4 protein levels and changes in SMARCA2-dependent gene expression were developed and will be used to assess selectivity and target engagement following treatment with PRT3789 in the ongoing Phase 1 clinical study.
  

About Prelude Therapeutics

Prelude Therapeutics is a clinical-stage precision oncology company developing innovative drug candidates targeting critical cancer cell pathways. The Company’s diverse pipeline is comprised of highly differentiated, potentially best-in-class proprietary small molecule compounds aimed at addressing clinically validated pathways for cancers with selectable underserved patients. Prelude’s pipeline includes four candidates currently in clinical development: PRT1419, a potent, selective inhibitor of MCL1, PRT2527, a potent and highly selective CDK9 inhibitor, PRT3645 a next generation CDK4/6 inhibitor, and PRT3789 an IV administered, potent and highly selective SMARCA2 degrader, and a preclinical oral candidate targeting SMARCA2.

For more information, visit our website and follow us on LinkedIn.

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, anticipated discovery, preclinical and clinical development activities for Prelude’s product candidates and the potential benefits of Prelude’s product candidates. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. Although Prelude believes that the expectations reflected in such forward-looking statements are reasonable, Prelude cannot guarantee future events, results, actions, levels of activity, performance or achievements, and the timing and results of biotechnology development and potential regulatory approval is inherently uncertain. Forward-looking statements are subject to risks and uncertainties that may cause Prelude's actual activities or results to differ significantly from those expressed in any forward-looking statement, including risks and uncertainties related to Prelude's ability to advance its product candidates, the receipt and timing of potential regulatory designations, approvals and commercialization of product candidates, clinical trial sites and our ability to enroll eligible patients, supply chain and manufacturing facilities, Prelude’s ability to maintain and recognize the benefits of certain designations received by product candidates, the timing and results of preclinical and clinical trials, Prelude's ability to fund development activities and achieve development goals, Prelude's ability to protect intellectual property, and other risks and uncertainties described under the heading "Risk Factors" in documents Prelude files from time to time with the Securities and Exchange Commission. These forward-looking statements speak only as of the date of this press release, and Prelude undertakes no obligation to revise or update any forward-looking statements to reflect events or circumstances after the date hereof. 

Investor Contact:
Lindsey Trickett
Vice President, Investor Relations
240.543.7970
ltrickett@preludetx.com

Media Contact:
Helen Shik
Shik Communications
617.510.4373
Helen@ShikCommunications.com