Boulder, Colorado, U.S., October 8, 2026
Edgewise Therapeutics, Inc. has announced the dosing of the first patient in its Phase 2 EQUINOX-HFpEF clinical trial, evaluating EDG-15400, an investigational oral therapy for adults with symptomatic heart failure with preserved ejection fraction (HFpEF). The study marks an important milestone in the company’s cardiovascular drug development program, which focuses on therapies designed to address underlying muscle dysfunction. EDG-15400 is an investigational selective cardiac sarcomere modulator intended to improve impaired cardiac relaxation, a key feature of HFpEF. Edgewise also announced plans to present the trial design and Phase 1 findings at the Heart Failure Society of America (HFSA) Annual Scientific Meeting 2026 in Phoenix, Arizona.
EQUINOX-HFpEF Trial Evaluates EDG-15400 in Adults
The Phase 2 EQUINOX-HFpEF trial is a multicenter, randomized, double-blind, placebo-controlled clinical study designed to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of EDG-15400. The company expects to enroll approximately 90 adults aged 30 to 84 years who have symptomatic HFpEF, a left ventricular ejection fraction (LVEF) of at least 50%, and New York Heart Association (NYHA) functional class II or III symptoms. Participants will receive once-daily oral doses of 25 mg or 50 mg of EDG-15400, or placebo, for up to 12 weeks. The study will assess how the investigational therapy behaves in the body, its biological activity, and its safety and tolerability in the target patient population.
The randomized, placebo-controlled design is intended to help researchers evaluate the effects of EDG-15400 while comparing outcomes against placebo. The trial represents an early clinical step toward determining whether the candidate’s proposed mechanism can translate into meaningful benefits for people living with symptomatic HFpEF. Kevin Koch, Ph.D., President and Chief Executive Officer of Edgewise Therapeutics, described the first-patient dosing milestone as an important step in evaluating EDG-15400’s potential to address impaired cardiac relaxation. The company aims to extend its cardiac sarcomere research platform into an area of cardiovascular disease where additional treatment options are needed.
EDG-15400 Targets Impaired Cardiac Relaxation
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EDG-15400 is an investigational oral, selective cardiac sarcomere modulator developed through Edgewise’s cardiovascular discovery platform. The candidate is intended to address impaired relaxation of the heart muscle, which can contribute to symptoms and disease burden in patients with HFpEF. HFpEF occurs when the heart retains a relatively preserved ejection fraction but does not relax and fill normally. This dysfunction can contribute to symptoms such as shortness of breath, fatigue, weakness, and swelling, potentially limiting patients’ daily activities and quality of life. Although treatment options for heart failure have advanced, impaired cardiac relaxation remains an important area of therapeutic research. Edgewise reports that EDG-15400 demonstrated improvements in diastolic function in preclinical models. These findings provide the scientific rationale for clinical investigation, but preclinical results do not establish safety or efficacy in humans. James L. Januzzi, M.D., Chair of the EQUINOX-HFpEF Executive Committee and the Hutter Family Professor of Medicine at Harvard Medical School, noted the ongoing challenges associated with HFpEF and the need for approaches that more directly address impaired cardiac relaxation. The Phase 2 trial will help determine whether EDG-15400’s proposed mechanism can demonstrate suitable safety, tolerability, and biological activity in adults with the condition.
Edgewise to Present Clinical Data at HFSA 2026
Alongside the trial announcement, Edgewise plans to present two EDG-15400-related presentations at the HFSA Annual Scientific Meeting, scheduled for October 9–12, 2026, in Phoenix, Arizona. The first presentation, an electronic poster titled EQUINOX-HFpEF: A Phase 2 Study of EDG-15400, a Selective Cardiac Sarcomere Modulator, in Adults with Heart Failure with Preserved Ejection Fraction, is scheduled for October 10. The second, a rapid-fire oral presentation titled EDG-15400, a Cardiac Sarcomere Modulator, Demonstrated Favorable Pharmacokinetics, Pharmacodynamics and Tolerability in Healthy Adult Participants, is scheduled for October 12. The presentations will provide an opportunity to share the Phase 2 study design and Phase 1 first-in-human findings with the cardiovascular research community. The first-patient dosing milestone advances EDG-15400 into Phase 2 evaluation, while further clinical data will be necessary to establish its potential role in HFpEF treatment.
Source: Edgewise Therapeutics press release
