Risankizumab Demonstrates Efficacy in Treating Individuals with Palmoplantar Psoriasis

Mark Lebwohl, MD

Credit: American Osteopathic College of Dermatology

Risankizumab (Skyrizi) therapy was effective and safe for patients with palmoplantar psoriasis, according to recent findings, with the medication meeting all primary and ranked secondary endpoints.¹

This new research was led by Mark Lebwohl, MD, the dean for clinical therapeutics and Chairman Emeritus of the Icahn School of Medicine at Mount Sinai department of dermatology.

Lewohl and colleagues noted that there was a general lack of randomized controlled trials looking at the palmoplantar psoriasis patient population.2 They noted that there had consequently been an unmet need for clinical decision-making among such patients.

“Risankizumab (RZB) is an approved IL-23 inhibitor targeting the p19 subunit with high affinity and specificity for the treatment of moderate-to-severe PsO, psoriatic arthritis, and Crohn's disease and has demonstrated efficacy in difficult-to-treat areas such as nails and scalp,” Lebwohl and colleagues wrote. “…The IMMprint phase IIIb study was designed to evaluate the safety and efficacy of RZB in patients with moderate-to-severe PsO with palmoplantar involvement.”¹

Background and Design

This phase 3b clinical study was known as the IMMprint trial, with the investigators’ work occurring in multiple centers. The study used a double-blind, randomized, parallel-group, placebo-controlled design. The team sought to assess both the safety profile and effectiveness of risankizumab 150 mg versus placebo among adults with moderate-to-severe plaque psoriasis and non-pustular palmoplantar disease involvement.

The investigators screened potential subjects for up to 35 days, with their 52-week treatment phase occurring afterward. They concluded their research with a safety follow-up phone call approximately 20 weeks following the final risankizumab dose at week 40.

In the study’s treatment phase, the research team used an initial double-blind segment, known as Period A, from the point of baseline to the 16-week mark. During this period, subjects were randomly assigned (1:1) by the team to be given either 150 mg subcutaneous risankizumab or a placebo at both the start of the study and at the 4-week mark.

They stratified the subjects based on their noted severity of palmoplantar involvement and body surface area (BSA) impacted by their disease. In Period B from the 16 - 52-week mark, all trial participants were treated with open-label risankizumab 150 mg via subcutaneous injection every 12 weeks. The final dose was administered at week 40.

The investigators’ criteria for eligibility for their analysis required subjects’ ages to be 18 years or older and required them to have chronic palmoplantar psoriasis for half a year minimum prior to the point of baseline. A ppIGA score of “moderate” or “severe” (≥3) was also required by the team at both screening and baseline, in addition to subjects being candidates for systemic treatment.

Subjects were also required by the research team to have a static Physician's Global Assessment (sPGA) score of “moderate” or “severe” (≥3), their disease impact at least 1% of their BSA, a Palmoplantar Psoriasis Area and Severity Index (PPASI) score of 8 at least, and at least a single psoriasis plaque outside the palms and soles at both the screening and the point of baseline.

Major Findings

The investigators’ primary goal was their evaluation of the proportion of participants who successfully achieved a ppIGA score of 0 or 1. Specifically, the subjects would have at least a 2-point improvement from the point of baseline by the 16-week mark.

In terms of secondary outcomes, the research team assessed whether subjects succeeded in PPASI 75, PPASI 90, sPGA 0/1 with 2-point reduction at least from baseline, and PPASI 100, all of which were looked into at the 16-week mark. They also monitored treatment-emergent adverse events (TEAEs) as well as vital signs, physical assessments, and laboratory evaluations.

The investigators found that risankizumab therapy significantly outperformed placebo by the 16-week mark in terms of ppIGA 0/1 response rates (33.3% versus 16.1% [P = .006]). The drug also outperformed PPASI 75 (42.5% versus 14.9% [P < .001]), sPGA 0/1 (32.2% versus 11.5% [P < .001]), PPASI 90 (27.6% versus 5.7% [P < .001]), and PPASI 100 (17.2% versus 1.1% [P < .001]).

These results identified by the research team were noted to have continued to improve through to the 52-week mark without any new safety concerns. The team reported that the proportion of subjects who noted AEs with any reasonable possibility of being associated with the analysis was shown to be 4.7% compared to 2.3% in the treatment and placebo arms, respectively.

“In conclusion, the IMMprint trial demonstrates the efficacy and tolerability of (risankizumab) in the treatment of (palmoplantar psoriasis),” they wrote. “(Risanizumab) met all primary and ranked secondary end points. These results provide robust evidence supporting the use of (risanizumab) as an effective treatment option for patients with (palmoplantar psoriasis) along with tolerable safety.”¹

References

1. ^{Lebwohl M, Bukhalo M, Bissonnette R, et al. A randomized phase 3b study evaluating the safety and efficacy of risankizumab in adult patients with moderate-to-severe plaque psoriasis with non-pustular palmoplantar involvement. J Am Acad Dermatol. 2024 Aug 30:S0190-9622(24)02747-6. doi: 10.1016/j.jaad.2024.07.1521. Epub ahead of print. PMID: 39208985.}
2. ^{Raposo I, Torres T. Palmoplantar psoriasis and palmoplantar pustulosis: current treatment and future prospects. Am J Clin Dermatol. 2016; 17:349-358.}