Thryv Therapeutics Secures FDA Clearance for THRV-1268, Paving the Way for Long QT Syndrome Treatment

On September 17, 2025, Thryv Therapeutics Inc., a Montreal-based biotechnology firm, announced a significant milestone in the treatment of Long QT Syndrome (LQTS) Type 2. The U.S. Food and Drug Administration (FDA) has granted clearance for Thryv's Investigational New Drug (IND) application for its lead compound, THRV-1268. This key development allows Thryv to commence its Phase 2/3 WAVE II clinical study, aimed at evaluating the safety and efficacy of THRV-1268 in patients suffering from this serious cardiac condition.

The WAVE II clinical study will focus on adult patients diagnosed with LQTS Type 2, specifically targeting those with a baseline corrected QT interval (QTc) exceeding 480 milliseconds. The primary endpoint of this study is to measure the mean change from baseline in the area under the curve for the QTc interval over a six-week treatment period. This rigorous evaluation is designed to assess the compound's effectiveness, regardless of any beta-blocker therapy the patients may be undergoing.

In conjunction with the FDA’s IND clearance, Thryv has successfully completed a financing round that will support the initiation of the WAVE II study. This financing reflects strong confidence in Thryv’s innovative science and leadership in the field of SGK1 inhibition. Notable investors include Amplitude Ventures, Fonds de solidarité FTQ, Lumira Ventures, Investissement Québec, adMare BioInnovations, and CTI Life Sciences Fund. Their participation not only provides the necessary capital but also brings invaluable expertise in cardiovascular development and global commercialization.

This clearance marks the second IND approval for Thryv in a short span of time, following the FDA's acceptance for THRV-1268 for the treatment of heart failure and atrial fibrillation. These approvals underscore the broad therapeutic potential of SGK1 inhibitors, positioning Thryv as a leader in the treatment of multiple serious cardiovascular diseases.

Paul Truex, Chairman and CEO of Thryv Therapeutics, expressed his enthusiasm regarding this latest development. "This FDA clearance and the launch of the Wave II Phase 2/3 study early next year represent major milestones in the development of what could become the first approved therapy for Long QT Syndrome," Truex stated. He emphasized Thryv's commitment to providing effective therapies that not only save lives but also enhance the quality of life for patients with LQTS.

Long QT Syndrome is a rare cardiac arrhythmia characterized by delayed ventricular repolarization, which manifests as a prolonged QT interval on an electrocardiogram (ECG). This condition significantly increases the risk of torsades de pointes, a potentially fatal ventricular tachyarrhythmia. Patients with LQTS are particularly vulnerable during periods of physical or emotional stress.

The condition has several subtypes, with Type 1, Type 2, and Type 3 being the most common, each linked to specific genetic mutations that influence the triggers for arrhythmic events. In addition to congenital forms of LQTS, acquired cases can arise, often due to medications that prolong the QT interval and heighten the risk of sudden cardiac death.

Thryv Therapeutics Inc. is a privately held company based in Montreal, Quebec, that specializes in the development of precision medicine solutions for cardiovascular diseases, including Long QT Syndrome, heart failure, and atrial fibrillation. The company is dedicated to advancing treatment options through potent and selective inhibitors of serum glucocorticoid inducible kinase 1 (SGK1).

As Thryv gears up for the WAVE II clinical study, the biotechnology community will be watching closely, as the outcome could have profound implications for patients suffering from this life-threatening condition.