Tildrakizumab shows long-term scalp psoriasis improvement

Key takeaways:

• This phase 3b clinical trial focused on safety and efficacy of the anti-IL-23 inhibitor in scalp psoriasis.
• Patients taking tildrakizumab had scalp improvement by 16 weeks, which continued through week 52.

Scalp psoriasis improvement was maintained with long-term tildrakizumab treatment in what researchers said is the first “dedicated trial” to demonstrate sustainable efficacy of an anti-interleukin-23 inhibitor for the condition.

“The scalp is a difficult-to-treat area for psoriasis and topical therapies are cosmetically unacceptable for many patients,” Howard L. Sofen, MD, clinical professor at the David Geffen School of Medicine at UCLA, and colleagues wrote. “Tildrakizumab is an anti-interleukin (IL)-23 p19 antibody approved for the treatment of adults with moderate to severe plaque psoriasis who are candidates for systemic therapy or phototherapy.”

This three-part, randomized, double-blind, placebo-controlled, phase 3b trial evaluated the safety and efficacy of tildrakizumab in hard-to-treat areas such as the scalp, which was not evaluated in the initial clinical trials.

Patients were randomly assigned to receive tildrakizumab 100 mg (n = 117) or placebo (n = 114) at weeks 0 and 4 in the study’s first part. At week 16, those originally assigned to tildrakizumab continued with every 12-week dosing through week 52, whereas those originally assigned to placebo received tildrakizumab at weeks 16, 20, 32 and 44. The trial’s third leg evaluated all patients who discontinued treatment during parts one and two who entered an off-treatment observational follow-up.

The modified intent-to-treat population was 89 patients in the initial tildrakizumab group and 82 in the placebo group. Treatment was discontinued in 22 patients in each group.

Patients were evaluated with the five-point IGA modified 2011 (scalp) score, with treatment success defined as a score of 0 or 1 with a two-grade or more improvement, as well as a 90% or more improvement in PASI score from baseline.

The proportion of patients initially treated with tildrakizumab that achieved IGA success at week 16 was 49.4% (n = 44/89) vs. 7.3% (n = 6/82) of the placebo group (P < .00001). PASI 90 response rate was achieved by 60.7% (n = 54/89) of the tildrakizumab-treated patients vs. 4.9% (n = 4/82) of the placebo-treated patients at the same time point group (P < .00001).

By week 52, these proportions increased to 62.9% (n = 56/89) of the tildrakizumab group vs. 56.1% (n = 46/82) of the crossover group for IGA success and 65.2% (n = 58/89) of the tildrakizumab group vs. 57.3% (n = 47/82) of the crossover group for PASI 90 response.

Additionally, Scalp Itch-Numerical Score Ratings improved from week 16 to 52 with mean scores decreasing from 3.4 ± 2.8 to 2.3 ± 2.6 in those treated with tildrakizumab.

Over the entire 72-week treatment period, treatment-emergent adverse events occurred in 53% of the treatment group and 51.8% of the crossover group, of which three and four, respectively, had serious events.

“These results demonstrate that the efficacy and safety of tildrakizumab for the treatment of scalp psoriasis are maintained through 52 weeks,” the authors wrote. “Key strengths of this study are that it was designed as a dedicated, long-term trial for the treatment of scalp psoriasis with stringent and clinically meaningful outcome measures.”