Viridian Therapeutics (Nasdaq: VRDN) reported Phase III data from the REVEAL-1 trial showing that elegrobart, a subcutaneous anti-IGF-1R monoclonal antibody, met its primary endpoint in active thyroid eye disease with a proptosis responder rate of 54% (Q4W) versus 18% for placebo at week 24 — positioning the drug as a potential first self-administered autoinjector in a market currently served only by intravenous therapy.
REVEAL-1 is a randomized, placebo-controlled Phase III trial enrolling 132 patients with active thyroid eye disease, randomized 1:1:1 across elegrobart Q4W, elegrobart Q8W, and placebo arms (n=44 each).
The Q4W arm met the FDA-defined primary endpoint of proptosis responder rate at 54% versus 18% placebo (p<0.0001). The Q8W arm, assessed as a secondary endpoint, produced a 63% responder rate against the same placebo comparator. Mean proptosis reduction from baseline by exophthalmometry was -2.33 mm (Q4W) and -2.50 mm (Q8W), compared with -0.81 mm for placebo. In the Q4W arm, 51% of patients achieved complete diplopia resolution versus 16% on placebo; this was one of several secondary measures reported by the company, but falls below the prespecified hierarchy break. The clinical activity score endpoint — reduction to 0 or 1 — was not statistically significant in the Q4W arm (57% vs 50%, p=0.24). The Q8W arm posted a nominally significant result on this measure (69% vs 50%, p=0.03), though interpretation is limited by the study’s testing hierarchy.
Adverse events were predominantly mild and consistent with the anti-IGF-1R class. Placebo-adjusted hearing impairment rates were 11.3% in the Q4W arm and 2.3% in the Q8W arm; all events were tinnitus, with no audiometric hearing loss reported.