Viridian Therapeutics, Inc. released positive topline data from the phase 3 REVEAL-2 clinical trial evaluating investigational elegrobart for the treatment of chronic thyroid eye disease (TED).
Hold up — didn’t Viridian just report phase 3 findings?
They did … at the end of March. However, that was in regard to a different phase 3 trial: REVEAL-1 (not REVEAL-2), which also evaluated elegrobart. But we’ll discuss that data later.
Got it. Now let’s get a refresher on this candidate.
Administered via a subcutaneous self-injection, eligrobart is an anti-insulin-like growth factor-1 receptor (IGF-1R) monoclonal antibody with two purposes:
- Blocking cell surface receptor activity
- Targeting antibody and protein engineering for specific diseases and autoimmune disorders (such as TED)
Its dosing regimen: every 4 (Q4W) or 8 weeks (Q8W)
And the clinical study?
REVEAL-2 (NCT06625398) is a randomized, double-masked, placebo-controlled efficacy, safety, and tolerability phase 3 study.
- The participants: 204 patients (aged 18 to 75) with moderate-to-severe chronic TED
- Full eligibility criteria here
- The setup: Patients randomized 1:1:1 to receive SC-administered doses of:
- Eligrobart Q4W (n = 70)
- Eligrobart Q8W (n = 68)
- Placebo Q4W (n = 66)
- The duration: Outcomes measured at Week 24
What was measured?
The primary outcome: Proptosis responder rate (PRR) in the study eye, as evidenced by a ≥2 mm reduction from baseline in proptosis
The secondary outcomes:
- Change from baseline in proptosis in the study eye
- Overall responder rate in the study eye
- Diplopia responder rate (DRR) for patients with baseline diplopia score >0
- Diplopia resolution rate for patients with baseline diplopia score > 0
All outcomes were measured at week 24.
Next up: the topline data.
High statistical significance was reached in REVEAL-2 as the study met its:
- Primary endpoint (p < 0.0001)
- 50% PRR for elegrobart Q4W
- 54% PRR for elegrobart Q8W
- Key secondary endpoints for proptosis in the Q4W and Q8W treatment arms
- 61% DRR for elegrobart Q4W (p = 0.018)
- 55% DRR for elegrobart Q8W (p = 0.0419)
Notably, the Q4W treatment arm also showed a statistically significant DRR at week 24—and efficacy was fairly consistent regardless of baseline clinical activity score (CAS).
Talk safety.
In general, elegrobart was well tolerated with a safety profile consisting of—largely mild—adverse events (AEs) typically expected from the anti-IG1R class.
Other notes:
- 91% of elegrobart-treated patients completed their full treatment course.
- No treatment-related serious AEs were reported.
- Low rates of hearing impairment were observed in both Q4W and Q8W treatment arms.
So … how do these results compare to REVEAL-1 data?
REVEAL-1 also met its primary outcome of PRR with highly statistically significant treatment effects among 54% of Q4W-dosed patients at week 24. Elegrobart was also found to be generally well-tolerated in each treatment group, with the majority of AEs mild and expected of anti-IGF-IRs.
- See here for more data points on this—including favorable secondary endpoint (such as DRR) outcomes.
Now let’s talk big picture for eligrobart.
Eligrobart has the potential to not only become the first autoinjector treatment for TED, but also—based on this latest data—enable clinically meaningful improvements in the signs and symptoms of the disease with as few as three doses.
Even more significant: It’s also reported to be the only subcutaneous program to demonstrate positive phase 3 data in both active and chronic TED pivotal clinical trials.
Potential indeed … so what’s the plan moving forward?
Regulatory approval. With the positive data readouts of REVEAL-1 for active TED and REVEAL-2 for chronic and active TED, Viridian shared plans to submit a Biologics License Application (BLA) for elegrobart in Q1 2027.
If approved, the therapy would become (in the company’s words) “a convenient, at-home treatment” for both active and chronic TED patients.
Nice! Also, we’d be remiss if we didn’t ask about Viridan’s other TED asset …
But of course. Veligrotug (also an IGF-IR monoclonal antibody)—the company’s lead program—is still on track for its own commercial pathway.
If you recall: The FDA accepted its BLA submission under priority review at the end of December 2025.
The latest update: Veligrotug’s Prescription Drug User Fee Act (PDUFA) target action date is still set for June 30, 2026.