Acelyrin, Inc. (NASDAQ: SLRN) has announced positive proof-of-concept data from an ongoing phase 1/2 trial of lonigutamab in thyroid eye disease (TED). Lonigutamab, a subcutaneously delivered humanized igg1 monoclonal antibody targeting the insulin-like growth factor-1 receptor (IGF-1R), demonstrated rapid improvements in proptosis and clinical activity score (CAS) at the first measurement within three weeks after the first subcutaneous dose.
The phase 1/2 trial, which is evaluating the safety and efficacy of lonigutamab dosed in TED patients, showed promising results. In cohort 1, which was placebo-controlled, 50% of patients receiving lonigutamab at 40mg every three weeks (q3w) achieved a proptosis response of ≥ 2 millimeter reduction from baseline, while 67% achieved a clinical activity score (CAS) response of ≥ 2 point reduction. In cohort 2, which is open label, patients receiving a 50mg loading dose followed by 25mg every week (qw) achieved a 50% proptosis response and an 83% CAS response. Furthermore, 25% of patients in cohort 2 achieved a diplopia response, indicating a clinically meaningful improvement.
The safety profile of lonigutamab has been favorable, with no reports of hyperglycemia or hearing impairment and no serious adverse events reported. Dr. Shao-Lee Lin, Founder and CEO of Acelyrin, expressed enthusiasm about the results, emphasizing the potential of lonigutamab to move patients towards resolution of their disease.
The positive data from the phase 1/2 trial have paved the way for a phase 2b/3 trial, which is planned to be initiated in the second half of 2024. This trial is designed to be the first of two registrational trials in TED, indicating a significant step forward in the clinical development of lonigutamab.
Today the company's shares have moved 4.3% to a price of $8.3. Check out the company's full 8-K submission here.
