Kymera Therapeutics Receives FDA Fast Track Designation For KT-621 To Treat Moderate To Severe Eosinophilic Asthma

Kymera Therapeutics, Inc., a clinical-stage biopharmaceutical company developing a new class of oral small-molecule degrader medicines for immunological diseases, announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to KT-621. This first-in-class oral STAT6 degrader is being developed for the treatment of moderate to severe eosinophilic asthma. KT-621 is currently being evaluated in two global Phase 2b studies, including one specifically focused on this form of asthma. Although several treatments already exist—such as inhalers and injectable biologics—there is still a clear need for effective, safe, and convenient oral therapies that can better support patients with uncontrolled disease.

Jared Gollob, MD, Chief Medical Officer of Kymera Therapeutics, explained that asthma is a chronic lung disease that can greatly impact daily living and become life-threatening in severe cases. He noted that many patients with moderate to severe asthma continue to struggle with symptoms despite current treatment options. According to him, KT-621, as a once-daily oral therapy, has the potential to ease treatment burden, improve disease control, and reach more patients. He added that receiving Fast Track designation gives the company an opportunity to work more closely with the FDA and explore ways to speed up the development of KT-621.

KT-621 has shown promising results so far. In preclinical asthma models, it demonstrated strong efficacy. In the BroADen Phase 1b trial—conducted in patients with atopic dermatitis who also had asthma—KT-621 reduced fractional exhaled nitric oxide (FeNO), a key biomarker of Type 2 inflammation in the lungs. It also improved asthma disease control (ACQ-5). These early findings indicate that KT-621 effectively degrades STAT6 and modulates Type 2 inflammation, supporting its potential benefits for asthma and other Type 2-driven diseases.

Kymera’s KT-621 BREADTH Phase 2b study in moderate to severe eosinophilic asthma is currently underway, with data expected in late 2027. The BROADEN2 Phase 2b trial in moderate to severe atopic dermatitis is also ongoing, with results anticipated by mid-2027. Both studies are designed to support accelerated development of KT-621 and help determine the optimal dosing for future Phase 3 registration trials across multiple inflammatory conditions.

The FDA’s Fast Track program aims to speed the development and review of drugs that treat serious conditions and address unmet medical needs. When a therapy receives Fast Track designation, the sponsor company may benefit from more frequent FDA interactions during development and may become eligible for accelerated approval or priority review if certain criteria are met. For more details about Fast Track designation, individuals can refer to the FDA’s official resources.