Risankizumab Proves Effective and Safe for Genital and Scalp Psoriasis: Study
Phase 4 results from the UnlIMMited trial show that risankizumab significantly improves psoriasis (PsO) symptoms in the genital and scalp regions, achieving higher clearance rates compared to placebo. The study found no new safety concerns, reinforcing risankizumab’s role as a reliable and well-tolerated therapy for treating moderate-to-severe psoriasis in these sensitive areas. The study was published in the journal of Dermatology and Therapy by Eingun J. and colleagues.
Despite the often limited extent of overall body surface area (BSA), PsO involving the genital and scalp areas places a disproportionate burden on patients' quality of life. Traditionally, such patients have been underrepresented in clinical trials and undertreated in clinical practice because their disease, based on BSA, is classified as mild or moderate. New clinical guidance now considers such patients to be candidates for advanced biologic therapies because of the striking physical and psychological impact of localized PsO. The
The ongoing phase 4, multicenter, randomized, double-blind, placebo-controlled UnlIMMited study (NCT05969223) has been designed to assess risankizumab for moderate-to-severe genital or scalp psoriasis. The study enrolled adult patients with either <10% or ≥10% BSA involvement.
Two parallel studies were conducted:
Study-G focused on genital psoriasis.
Study-S focused on scalp psoriasis.
Patients were randomized 1:1 within each subgroup to receive either risankizumab 150 mg or placebo administered at week 0 and week 4. Primary endpoints were:
Achievement of static Physician's Global Assessment-Genital (sPGA-G) 0/1 for Study-G
Achievement of Scalp Investigator's Global Assessment (IGA) 0/1 for Study-S, both at week 16.
Secondary endpoints were assessments of skin clearance, symptom resolution, and quality of life improvements, which were also assessed at week 16. Safety data were monitored throughout the first 16 weeks of the trial.
Key Findings
At week 16, risankizumab was significantly more effective than placebo for both genital psoriasis and scalp psoriasis:
In Study-G (genital psoriasis):
Among patients receiving risankizumab, 69.1% achieved sPGA-G 0/1 compared to 13.0% in the placebo group (P < 0.0001).
In Study-S (scalp psoriasis):
Among those receiving risankizumab, 60.8% achieved scalp IGA 0/1 versus 13.0% with placebo (P < 0.0001).
Moreover, secondary endpoints consistently demonstrated improvements in skin symptom relief, lesion clearance, and patient-reported quality of life in both studies.
No new safety signals were observed, confirming the established safety profile of risankizumab from previous trials in plaque psoriasis.
The UnlIMMited phase 4 study showed that risankizumab is highly effective and well-tolerated in the treatment of both genital and scalp psoriasis. These findings support the inclusion of risankizumab as a valuable treatment option for patients with psoriasis of sensitive, high-impact areas, even when overall disease extent is limited.
Reference:
Song, E.J., Ehst, B., Glick, B. et al. Efficacy and Safety of Risankizumab in Genital or Scalp Psoriasis in the UnlIMMited Phase 4 Randomized Clinical Trial at Week 16. Dermatol Ther (Heidelb) (2025). https://doi.org/10.1007/s13555-025-01544-6
