Why Is Viridian Therapeutics Stock Sinking Monday?

Viridian Therapeutics Inc. (NASDAQ:VRDN) shares fell sharply Monday following topline Phase 3 data from Amgen Inc. (NASDAQ:AMGN) for TEPEZZA in thyroid eye disease (TED), intensifying competitive pressure in the space.

Amgen Data Raises Competitive Pressure

The Phase 3 TEPEZZA OBI trial met its primary endpoint, showing a statistically significant 77% proptosis (bulging eyes) response rate among participants during the 24-week placebo-controlled period.

The study demonstrated a mean proptosis reduction of -3.17.

Last week, Viridian Therapeutics shared topline results from the REVEAL-1 Phase 3 clinical trial for elegrobart for thyroid eye disease.

Viridian Data Falls Short Of Expectations

The REVEAL-1 trial met its primary endpoint, showing a statistically significant treatment effect with elegrobart achieving a proptosis (abnormal protruding eyes) responder rate of 54% and 63% for the Q4W (once in four weeks) and every eight weeks (Q8W) dosing regimens, respectively, compared to 18% for placebo at week 24.

But the stock fell on weaker efficacy relative to peers, which could raise investor concerns about commercial viability.

The placebo-adjusted proptosis responder rates of 36% (Q4W) and 45% (Q8W) came in below the 51%-73% range that investors were looking.

Viridian Therapeutics Pipeline Strategy

Topline data from the REVEAL-2 study for chronic TED, the second pivotal phase 3 trial of elegrobart, remains on track to read out in the second quarter of 2026.

Viridian anticipates submitting a Biologics License Application (BLA) to the US FDA for elegrobart in the first quarter of 2027.

The company ended the fiscal 2025 with $875 million in cash, which it expects will support its business plans through to profitability, particularly with anticipated revenues from elegrobart and veligrotug if approved.

The veligrotug application is under Priority Review at the FDA with a Prescription Drug User Fee Act (PDUFA) target action date of June 30.

Analyst View

William Blair on Monday wrote, “We believe Viridian’s veligrotug and elegrobart have the potential to capture significant share in the TED market. We believe veligrotug offers a competitive profile relative to current standard-of-care Tepezza, and believe the more convenient dosing and diplopia benefits in chronic TED should translate into a meaningful commercial opportunity if approved by its June 30 PDUFA date.”

Peers Landscape

In December 2025, Argenx SE (NASDAQ:ARGX) announced it would discontinue the Phase 3 UplighTED studies evaluating efgartigimod subcutaneous (SC) (efgartigimod alfa and hyaluronidase-qvfc) in adults with moderate to severe TED.

VRDN Stock Price Activity: Viridian shares were down 22.03% at $14.69 at the time of publication on Monday, according to Benzinga Pro data.

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