A ‘TYK’ Above Placebo: ICP-488 in Plaque Psoriasis

Photo Credit: tumeyes

Once-daily ICP-488, a selective oral tyrosine kinase 2 (TYK2) inhibitor, significantly improved PASI scores in patients with moderate-to-severe plaque psoriasis compared with placebo at week 12, with a safety profile similar to placebo.

The phase 2 trial was presented by Dr. Xiaoguang Zhang, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China.¹ The study randomly assigned 129 participants aged 18 to 70 years in a 1:1:1 ratio to receive 6 mg ICP-488, 9 mg ICP-488, or placebo for 12 weeks, followed by a 28-day safety assessment. The primary end point was the percentage of participants who achieved at least a 75% improvement from baseline in the Psoriasis Area and Severity Index score (PASI75) at week 12.

At week 12, ICP-488 achieved significant PASI improvements; thus, the study met the primary end point. The 6-mg group showed a 78% reduction, and the 9-mg group achieved an 82.3% reduction, compared with 26.5% in the placebo group. PASI75 was reached by 77.3% of the 6-mg group and 78.6% of the 9-mg group versus 11.6% in the placebo group (P<0.0001). Additional response rates included PASI50 (88.6% and 92.9%), PASI90 (36.4% and 50%), and PASI100 (~11% in both doses), all significantly higher than placebo.

Moreover, static Physician’s Global Assessment (sPGA) scores of 0 or 1 were achieved by 70.5% in the 6-mg group and 71.4% in the 9-mg group, compared with 9.3% in the placebo group, indicating nearly clear or completely clear skin.

The safety analysis revealed no serious treatment-emergent adverse events (TEAEs), and most moderate TEAEs were unrelated to ICP-488. No participants discontinued due to treatment-related issues, and the overall safety profile was comparable with placebo.

“These findings highlight ICP-488 as a highly effective and very well-tolerated oral therapy for plaque psoriasis,” Dr. Zhang concluded. “A high proportion of patients achieved PASI75 in both doses, demonstrating outstanding efficacy.”

Medical writing support was provided by Dr. Rachel Giles.
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