Viridian Reports Positive Phase 3 Results for Elegrobart in Thyroid Eye Disease
Viridian Therapeutics reported positive Phase 3 results for elegrobart in thyroid eye disease, showing significant proptosis reduction and diplopia resolution. The company plans a BLA submission in Q1 2027 and has another IGF-1R inhibitor, veligrotug, under FDA Priority Review with a June 2026 decision date.
Viridian Therapeutics has announced positive topline results from its Phase 3 REVEAL-1 clinical trial evaluating elegrobart in patients with active thyroid eye disease. The study met its primary endpoint with high statistical significance, showing robust proptosis responses and meaningful improvements in double vision. The company anticipates submitting a Biologics License Application for elegrobart in the first quarter of 2027.
The REVEAL-1 study enrolled 132 patients and evaluated two dosing schedules for subcutaneous elegrobart—every four weeks (Q4W) and every eight weeks (Q8W)—compared with placebo. Elegrobart achieved a 54% proptosis responder rate in the Q4W arm and 63% in the Q8W arm, versus 18% for placebo. The therapy also produced complete resolution of diplopia in 51% of patients treated Q4W versus 16% on placebo at week 24.
Elegrobart is a subcutaneously delivered, half-life-extended monoclonal antibody targeting the insulin-like growth factor-1 receptor. The treatment regimen required as few as three subcutaneous doses, positioning elegrobart as a potentially convenient alternative to the currently marketed therapy that requires eight intravenous infusions. The therapy was generally well tolerated with low rates of hearing impairment.
REVEAL-2, a Phase 3 clinical trial evaluating elegrobart in patients with chronic thyroid eye disease, is on track for topline readout in the second quarter of 2026. Viridian ended 2025 with approximately $875 million in cash, cash equivalents and marketable securities. The company said that its current cash position, together with potential near-term milestones from its royalty agreement and anticipated commercial revenues from veligrotug and elegrobart if approved, is expected to fund its business plans through profitability.
In addition to elegrobart, Viridian has another IGF-1R inhibitor in its pipeline called veligrotug, which is under Priority Review with a PDUFA target action date of June 30, 2026. Veligrotug has received both Breakthrough Therapy Designation and Priority Review from the FDA. The company is preparing its commercial team to launch the intravenous drug immediately if approved.