Viridian Reports Positive Phase III REVEAL-2 Data for Elegrobart in Chronic Thyroid Eye Disease

Viridian Therapeutics, a US-based biotechnology company, has reported positive topline results from a phase 3 clinical trial (REVEAL-2) evaluating elegrobart in patients with chronic thyroid eye disease (TED), with the study meeting its primary endpoint and demonstrating statistically significant improvements across multiple efficacy measures.¹

Elegrobart, a subcutaneously delivered, half-life extended monoclonal antibody targeting the insulin-like growth factor 1 receptor (IGF-1R), was assessed in two dosing regimens of every four weeks (Q4W) and every eight weeks (Q8W) compared with placebo in 204 patients randomized 1:1:1.

The REVEAL-2 study met its primary endpoint for both FDA and the European Medicines Agency (EMA) with high statistical significance (p < 0.0001). Proptosis responder rates at week 24 reached 50% in the Q4W group and 54% in the Q8W group, compared with 15% for placebo. Mean proptosis reductions were −1.9 mm and −2.1 mm for Q4W and Q8W dosing, respectively, versus −0.5 mm with placebo.¹

How did elegrobart perform across key efficacy endpoints in REVEAL-2?

In addition to the primary endpoint, the study met all proptosis-related key secondary endpoints in both dosing arms. The overall responder rate, defined by combined proptosis and clinical activity score response, was 47% in the Q4W arm and 54% in the Q8W arm, compared with 15% in the placebo group (p < 0.0001 for both comparisons).¹

Diplopia outcomes also showed improvement. The Q4W group achieved a statistically significant diplopia responder rate of 61% at week 24 compared with 38% in the placebo group (p = 0.0118). The Q8W group reported a 55% responder rate (p = 0.0419). Complete resolution of diplopia occurred in 44% of patients in the Q4W arm and 36% in the Q8W arm, compared with 25% in the placebo arm.¹

“We are excited by today’s positive REVEAL 2 results and view these data as a major step forward for the chronic TED patient population,” said Steve Mahoney, president and chief executive officer of Viridian Therapeutics, in a company press release.¹ “Given the IV [intravenous]-like proptosis response and our plans to launch with an at-home autoinjector, we believe elegrobart can meaningfully attract chronic patients to seek treatment.”

What safety profile was observed in the phase 3 study?

Elegrobart was generally well tolerated across both dosing regimens. The safety profile was consistent with that observed in an earlier REVEAL-1 trial and aligned with expectations for the anti-IGF-1R class. Most adverse events were mild in severity, according to the company.

Rates of hearing impairment were low, with placebo-adjusted rates of 4.1% in the Q4W group and 8.8% in the Q8W group. A total of 91% of patients receiving elegrobart completed the full treatment course. No treatment-related serious adverse events were reported, the company stated in its release.¹

“Chronic TED remains a challenging condition,” said John Mandeville, MD, PhD, oculoplastic surgeon at Ophthalmic Consultants of Boston and clinical associate at Massachusetts General Hospital, in the release.¹ “Many patients have been living with this disease for years or decades and would benefit from an effective and convenient treatment option. These REVEAL 2 results demonstrate the potential for elegrobart to provide meaningful improvement in the signs and symptoms of TED in as few as three doses.”

What are the next regulatory and pipeline milestones?

REVEAL-2 represents the second successful pivotal phase 3 trial for elegrobart, following positive results from the REVEAL-1 study in active TED, the company reported.^1,2 Viridian stated it remains on track to submit a biologics license application to FDA in the first quarter of 2027.

The company is also advancing veligrotug, another IGF-1R-targeting therapy and its lead program for TED. Veligortug is currently under priority review with a Prescription Drug User Fee Act target action date of June 30, 2026.

References

1. Viridian Therapeutics. Viridian Therapeutics announces positive topline results from Elegrobart phase 3 REVEAL‑2 clinical trial in chronic thyroid eye disease. Published May 5, 2026. Accessed May 5, 2026. https://investors.viridiantherapeutics.com/news/news-details/2026/Viridian-Therapeutics-Announces-Positive-Topline-Results-from-Elegrobart-Phase-3-REVEAL2-Clinical-Trial-in-Chronic-Thyroid-Eye-Disease/default.aspx
2. An efficacy, safety, and tolerability study of VRDN-003 in participants with chronic thyroid eye disease (TED) (REVEAL-2). ClinicalTrials.gov identifier: NCT06625398. Updated Sept. 30, 2025. Accessed May 5, 2026. https://clinicaltrials.gov/study/NCT06625398