Viridian Reports Positive Long-Term Durability Data from Phase 3 TED Study

Rare Daily Staff

Viridian Therapeutics reported positive long-term durability data from its THRIVE phase 3 clinical trial of its experimental therapy, veligrotug, to treat patients with the rare autoimmune condition, active thyroid eye disease.

Thyroid eye disease (TED) is a progressive, debilitating, and potentially vision-threatening rare autoimmune disease. TED often occurs in people living with Graves’ disease, but it is a distinct condition caused by autoantibodies activating an IGF-1R-mediated signaling complex on cells within the retro-orbital space. This leads to a cascade of events that may cause long-term, irreversible damage, including blindness. Symptoms of TED may include dry eyes and grittiness, redness, swelling, excessive tearing, eyelid retraction, proptosis, pressure and/or pain behind the eyes, and double vision.

Veligrotug is an intravenously delivered, anti-insulin-like growth factor-1 receptor (IGF-1R) antibody in phase 3 development for TED, with the potential to be the IV treatment of choice for both active and chronic TED patients. IGF-1R is a clinically and commercially validated target for TED, with U.S. revenues of approximately $2 billion in 2024. Veligrotug has the potential to improve patient experience with a differentiated dosing regimen featuring a shorter infusion time and fewer infusions compared to the currently approved and marketed IGF-1R inhibitor

The company previously reported that in its pivotal phase 3 clinical trials, THRIVE and THRIVE-2, veligrotug met all primary and secondary endpoints.

Some 70 percent of veligrotug patients in the THRIVE study, who were proptosis responders at week 15 and continued follow-up to the end of the study at week 52, maintained their proptosis response. Maintenance of response is defined as responders at week 15 who still had at least a 2-millimeter reduction in proptosis compared to baseline at week 52, without worsening in the fellow eye, as measured by exophthalmometry.

There were no changes to the safety profile in the follow-up period. The vast majority of adverse events reported at the week 15 primary analysis had resolved by week 52.

The company expects to apply to the U.S. Food and Drug Administration in the second half of 2025 for approval to market veligrotug with a potential launch in 2026. The FDA granted Veligrotug Breakthrough Therapy designation, which makes it potentially eligible for a priority review.

“We view the strength of today’s durability and safety resolution data as reinforcing veli’s strong and consistently robust clinical profile,” said Steve Mahoney, Viridian’s president and CEO. “We believe that the totality of veligrotug’s clinical data continues to demonstrate its potential to be the treatment-of-choice for patients living with TED. We believe these data, together with a streamlined dosing regimen of five infusions, position veli to become a market leading TED therapeutic, if approved.”

Photo: Steve Mahoney, Viridian’s president and CEO