PRT13722 / Prelude Therap - LARVOL DELTA

Prelude Therapeutics announced that the U.S. FDA cleared the Company to proceed with a Phase 1 study under its Investigational New Drug Application for PRT13722, an oral KAT6A selective degrader being developed for the treatment of patients with HR+/HER2- breast cancer. (The Manila Times) - "The Company expects to begin enrolling patients in the fourth quarter of 2026. The Phase 1 study is a first-in-human, open-label, multicenter study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and antitumor activity of PRT13722 as monotherapy and in combination with endocrine and targeted therapies in adults with locally advanced or metastatic HR-positive, HER2-negative breast cancer.”"

IND • New P1 trial • HER2 Negative Breast Cancer • Hormone Receptor Positive Breast Cancer

Highly selective KAT6A oral degrader program (PreludeDx Press Release) - "Pending clearance of the IND application, the Company expects the phase 1 study initiation of PRT13722 in HR+ breast cancer in the fourth quarter of 2026."

New P1 trial • Hormone Receptor Positive Breast Cancer

Prelude Therapeutics…provided an update on its R&D pipeline and other corporate developments (PreludeDx Press Release) - "Initiated enrollment of Phase 1 Study of PRT12396, mutant-selective JAK2V617F inhibitor in patients with polycythemia vera (PV) and myelofibrosis (MF), PRT13722 remains on track to file an IND application in mid-2026, and pending clearance, phase 1 study initiation expected in the 2nd half of 2026."

Enrollment status • IND • New P1 trial • Breast Cancer • Estrogen Receptor Positive Breast Cancer • Myelofibrosis • Polycythemia Vera

Highly selective KAT6A oral degrader program (GlobeNewswire) - "The Company expects to file the IND for PRT13722, first-in-class highly-selective oral KAT6A degrader, by mid-2026 with Phase 1 study initiation in ER+ breast cancer anticipated in the 2H 2026."

IND • New P1 trial • Estrogen Receptor Positive Breast Cancer

First-in-class potent and selective oral KAT6A degrader development candidate, PRT13722, drives complete tumor regressions as a monotherapy with an improved pre-clinical hematological safety profile (AACR 2026) - "Targeting KAT6 has recently been clinically validated in ER+/HER2- breast cancer (BC) and is being evaluated in Phase 3 trials in combination with fulvestrant (FUL). In summary, our first-in-class potent and selective oral KAT6A degrader, PRT13722, demonstrates improved efficacy and the potential for reduced off-target neutropenia compared to certain clinically validated KAT6A/B dual inhibitors. IND filing for PRT13722 is on track for mid-2026."

Monotherapy • Preclinical • Breast Cancer • Estrogen Receptor Positive Breast Cancer • HER2 Breast Cancer • HER2 Negative Breast Cancer • HER2 Positive Breast Cancer • Oncology • Solid Tumor • CDK4 • ER • HER-2 • KAT6A • KAT6B • PIK3CA

Prelude Therapeutics Presents Preclinical Data from Development Candidate, PRT13722, a First-in-Class, Orally Bioavailable, Potent and Highly Selective KAT6A Degrader at American Association for Cancer Research (AACR) Annual Meeting 2026 (The Manila Times) - "PRT13722 drives durable complete tumor regressions in HR+/HER2- xenograft models (both endocrine therapy (ET) sensitive and experienced) at well-tolerated doses, as a monotherapy; PRT13722 is synergistic with ET, CDK4/6 inhibitors, and PI3Kα inhibitors while maintaining monotherapy and combination activity across HR+ BC models, including estrogen receptor 1 mutated and acquired therapy-resistant cancer cells; PRT13722 has an improved preclinical hematological safety profile compared to prifetrastat, which may enable combinations with standard of care agents in HR+ BC; PRT13722 is on track for IND filing in mid-2026....subject to clearance, with Phase 1 study initiation planned in the 2nd half of 2026."

IND • New P1 trial • Preclinical • HER2 Negative Breast Cancer • Hormone Receptor Positive Breast Cancer

Prelude Therapeutics Announces Acceptance of Preclinical Abstract for PRT13722, a First-in-Class Oral KAT6A Selective Degrader at the 2026 AACR Annual Meeting (GlobeNewswire) - "'We expect to file an IND in the middle of this year and enter clinical trials in the second half of 2026'."

IND • Preclinical • Solid Tumor

Highly selective KAT6A oral degrader program (GlobeNewswire) - "The Company has selected a development candidate and remains on track to file an IND in mid-2026 with phase 1 study initiation planned in the 2nd half of 2026."

IND • New P1 trial • Estrogen Receptor Positive Breast Cancer

Highly selective KAT6A oral degrader program (GlobeNewswire) - "The Company has selected a development candidate and is on track to file an IND in mid-2026 and initiate a phase 1 dose escalation study in the second half of 2026."

IND • New P1 trial • Estrogen Receptor Positive Breast Cancer

Highly selective KAT6A oral degrader program (GlobeNewswire) - "The Company is now advancing a development candidate and remains on track to file an IND in the first half of 2026."

IND • Estrogen Receptor Positive Breast Cancer • Solid Tumor