The US Food and Drug Administration (FDA) has accepted the filing of a Biologics License Application (BLA) for imsidolimab for the treatment of generalised pustular psoriasis (GPP), with a target action date of 12 December 2026.
GPP is a rare, chronic, life-threatening autoinflammatory skin disorder characterized by sudden flares of widespread pustules, erythema, and systemic symptoms such as fever and fatigue.
The pathogenesis of GPP is increasingly understood through its genetic characterisation (OMIM #614204), and its molecular etiology is mainly attributed to excessive activity of the interleukin-36 (IL-36) pathway.1 The majority of GPP cases for which a causal single gene defect has been identified are caused by various consequential genetic variants in the IL36RN gene, encoding the IL-36 receptor antagonist (IL-36Ra).2,3,4
Imsidolimab, developed by Vanda Pharmaceuticals, is a fully humanised IgG4 monoclonal antibody that inhibits IL-36 receptor signalling and is believed to achieve its therapeutic effects in GPP where IL-36 signalling is unbalanced.
If approved, imsidolimab could address a significant unmet medical need in this rare and life-threatening disorder with potential benefits over currently existing treatments.
Imsidolimab was studied in global clinical studies conducted in the United States, France, Spain, Poland, Turkey, Malaysia, Thailand, Georgia, Tunisia, Taiwan, and Morocco.
In the pivotal efficacy studies GEMINI-1 and GEMINI-2, a single intravenous dose of imsidolimab led to rapid disease clearance, with 53% of patients achieving clear or almost clear skin (GPPPGA 0/1) at week four compared to 13% on placebo. Efficacy was maintained throughout an approximately two-year maintenance period with monthly doses, and no flares occurred in the active treatment arm.
Imsidolimab exhibited a favourable safety profile and demonstrated a low incidence of anti-drug antibodies, which can be a significant advantage over existing treatments. GPP is a rare disorder with prevalence estimates varying widely by region, ranging from approximately 2 to 124 cases per million worldwide (lower in Europe and higher in parts of Asia).5,6
References were supplied.