Viridian reports positive phase 1 data for VRDN-008, an FcRn inhibitor

Viridian Therapeutics announced on November 9, 2026 positive phase 1 results for VRDN-008, a half-life extended bifunctional FcRn inhibitor which the company said supports a potential best-in-class profile with every-eight-week subcutaneous dosing.¹

The trial tested VRDN-008 in six healthy volunteers. It showed deep and sustained IgG reduction through eight weeks after subcutaneous dosing, with a 74% reduction at peak.¹ The drug's half-life measured 15 to 18 days, which the company said was five to six times longer than first-generation Fc fragments.¹ Viridian also reported that the safety profile spared albumin and low-density lipoprotein and was generally well tolerated.¹

Based on pharmacokinetic modeling, the company said the data support moving both every-eight-week and every-four-week subcutaneous dosing schedules forward into registrational testing.¹

Looking ahead, Viridian plans to start at least one pivotal clinical trial in 2027, beginning with myasthenia gravis in mid-2027, pending regulatory feedback.¹ That planned MG study would be a multi-arm trial using the enFuse delivery device, comparing four-week and eight-week dosing against placebo, with the aim of supporting a direct path to registrational approval, pending regulatory feedback.¹

Viridian said its near-term FcRn pipeline focus will remain on VRDN-008. The company plans to concentrate its FcRn inhibitor development on advancing VRDN-008 further, while it may pursue VRDN-006 development at a later time.¹ VRDN-008 is licensed from Paragon Therapeutics, Inc. and combines an Fc fragment with an albumin-binding domain designed to prolong IgG suppression for subcutaneous delivery.¹