Prelude Therapeutics announces publication of abstract on PRT3789

Prelude Therapeutics announced the publication of an abstract regarding PRT3789 at the European Society of Medical Oncology Congress 2024 taking place in Barcelona, Spain September 13-17, 2024. PRT3789 is a potent and highly selective, first-in-class SMARCA2 degrader, in Phase 1 clinical development in biomarker selected SMARCA4 mutant patients. Enrollment remains on track, and the Company expects to conclude monotherapy dose escalation by year end 2024 and identify a recommended Phase 2 dose. In addition, enrollment of patients into back-fill cohorts enriched for NSCLC and SMARCA4 loss-of-function mutations is ongoing. Objectives for this first Phase 1 clinical study are to establish the safety and tolerability profile of PRT3789 as both monotherapy and in combination with docetaxel, evaluate activity, pharmacokinetics and pharmacodynamics and determine a dose and potential indications for advancement into a registrational clinical trial. Oral presentation title: First Clinical Results from a Phase 1 Trial of PRT3789, a First-in-Class Intravenous SMARCA2 Degrader, in Patients with Advanced Solid Tumors with a SMARCA4 Mutation. Observations in the abstract include: As of the March 7, 2024 data cutoff date, 40 pts had been enrolled; Dose escalation had proceeded through 6 levels, from 24-212 mg, with 2 backfill cohorts opened; No DLTs or study drug-related SAEs have been reported; The most common AEs reported, of any grade or relatedness, are nausea , constipation and dyspnea, decreased appetite and fatigue, and anemia; Dose-related increases in AUC were observed; Dose-dependent decreases in SMARCA2 levels were seen at all doses with a trend for increasing depth and duration with increasing doses; Minimal effects on SMARCA4 levels were seen; Clinical activity of PRT3789 therapy noted to date includes RECIST partial responses, tumor shrinkage and prolonged stable disease in patients with advanced, heavily pretreated esophageal cancer and NSCLC.