FDA gives rare disease boost to Qivigy for stiff person syndrome

Summary

The FDA has granted Orphan Drug Designation to Qivigy (immune globulin intravenous) for stiff person syndrome (SPS), a rare and debilitating neurologic disorder. Currently approved for primary humoral immunodeficiency, Qivigy is now being evaluated in a clinical trial for SPS. No treatments are currently FDA-approved specifically for SPS in the US.

The FDA has granted Orphan Drug Designation to Qivigy (immune globulin intravenous, human-kthm; Kedrion Biopharma) for the treatment of stiff person syndrome (SPS) — a rare, immune-mediated neurologic disorder marked by progressive muscle rigidity and painful spasms that can severely limit mobility and daily functioning. Currently, no products are specifically approved in the US for SPS.

Qivigy is already approved as a 10% intravenous immune globulin formulation for adults with primary humoral immunodeficiency. Its safety and effectiveness in SPS have not yet been established, and an ongoing clinical trial (NCT07552987) is actively evaluating its use in this population.

Key Takeaways

Orphan Drug Designation applies to therapies targeting rare conditions affecting fewer than 200,000 Americans
The designation unlocks development incentives: tax credits, fee waivers, grants, and potential market exclusivity post-approval
Qivigy carries a Boxed Warning for thrombosis, renal dysfunction, and acute renal failure
Other notable risks include hypersensitivity, aseptic meningitis, hemolysis, and transfusion-related acute lung injury

Why it matters: For neurologists managing SPS patients, this designation signals a meaningful regulatory step toward a formally studied treatment option for a condition that currently has no approved therapies in the US.

Curie Brief

Curie Brief