Atrogi Begins Dosing in 8-Week Human Study of GRK2-Biased β2 Agonist ATR-258

Overview

• First participants received daily oral ATR-258 in an investigator-initiated, 8-week interventional study of overweight male volunteers.
• The trial, led by Associate Professor Morten Hostrup at the University of Copenhagen, examines biased β2-adrenergic receptor signaling with detailed muscle physiological and molecular readouts.
• ATR-258 is a first-in-class, long-acting, oral GRK2-biased β2-agonist designed to stimulate muscle metabolism and preserve lean mass while aiming to avoid cardiovascular side effects linked to classic β2 agonists.
• The program builds on a June 2025 Cell publication that validated the GRK2-biased approach and reported Phase 1 safety and tolerability in a 69-subject study including healthy volunteers and people with type 2 diabetes.
• Findings from this muscle-physiology study, registered as NCT07421024, are expected later in 2026 to inform potential use in metabolic diseases and conditions involving muscle wasting.