HAYA Therapeutics doses first cohort in Phase 1 trial of a precision therapy for cardiac fibrosis

Swiss-American biotech HAYA Therapeutics has dosed the first cohort in the Phase 1 clinical trial of HTX-001, its lead investigational therapy and a first-in-class candidate aimed at the underlying fibrosis that drives heart disease.

HTX-001 is an antisense oligonucleotide designed to downregulate WISPER, a heart stress-specific long non-coding RNA (lncRNA) that is overexpressed in patients with hypertrophic cardiomyopathy. By lowering WISPER expression in cardiac myofibroblasts, the therapy is intended to reprogramme this fibrotic, disease-driving cell population back toward a healthy state. In preclinical studies, the company reports, HTX-001 reduced pathological cardiac fibrosis and improved heart function.

The trial’s initial focus is nonobstructive hypertrophic cardiomyopathy (nHCM), which accounts for an estimated 30–60% of all hypertrophic cardiomyopathy cases and is marked by thickened heart walls, impaired diastolic function, and significant fibrosis. Crucially, today’s available treatments do not directly address the fibrotic process itself — leaving a clear gap that HAYA is targeting.

“A targeted anti-fibrotic therapy for nHCM offers the potential to address an important unmet medical need, as currently available treatments fail to address the underlying fibrotic process that drives disease,” said Jordan Shin, M.D., Ph.D., Chief Medical Officer of HAYA Therapeutics.

The milestone caps a journey that began with the science itself. WISPER was first discovered in 2017 by Samir Ounzain, Ph.D., HAYA’s co-founder and CEO, who identified its role in cardiac fibrosis and remodeling. He went on to co-found the company with Daniel Blessing, Ph.D., co-founder and CSO, whose team translated HTX-001 from concept into a clinical candidate.

“With HTX-001, we are translating that biology into an investigational precision RNA-guided therapy designed to enable the reprogramming of cardiac fibroblasts, the sentinel effector cells of cardiac fibrosis,” Ounzain said. Blessing called the dosing “a meaningful milestone for the entire HAYA team as we advance our science from the laboratory into clinical development.”

The Phase 1a/b study will evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of HTX-001 across multiple-ascending-dose cohorts — first in healthy volunteers, then in nHCM patients.

HTX-001 is investigational and has not been approved by the FDA, EMA, or any other regulatory authority; its safety and clinical benefit remain to be established.

Headquartered at the Biopôle life-sciences park in Lausanne, with laboratory facilities at Lilly Gateway Labs in San Diego, HAYA is developing a broader pipeline of RNA-guided medicines targeting fibrosis-driven and chronic, age-related diseases. The company raised a $65 million Series A in 2025 to advance the platform.

➡️ Source: Press Release | 📸 ©Haya Therapeuthics