Understanding Temtokibart's Potential in Atopic Dermatitis, With Stephan Weidinger, MD, PhD

New results presented at the European Academy of Dermatology and Venereology (EADV) 2025 Congress suggest that temtokibart, an investigational monoclonal antibody targeting the IL-22RA1 receptor subunit, may represent a novel therapeutic strategy for adults with moderate-to-severe atopic dermatitis.

“These results are promising, as they provide further evidence of the value of targeting the IL-22 pathway in AD, via IL-22RA1 , offering a potential novel approach to the currently existing therapies used to treat atopic dermatitis” said Stephan Weidinger, MD, PhD, professor and chair for Dermatology at the Christian-Albrechts-University, director of the Department of Dermatology and Allergy at the University Hospital Schleswig-Holstein,

The late-breaking phase 2b trial randomized 262 adult patients with moderate-to-severe atopic dermatitis to 1 of 4 temtokibart dose arms or placebo. The study was designed to evaluate efficacy, measured by percent change in Eczema Area and Severity Index (EASI) from baseline to week 16, and safety, assessed by treatment-emergent adverse events.

At week 16, temtokibart demonstrated significant improvements in EASI scores compared with placebo across multiple dosing groups:

• 600 mg: −61.2% (P < .01)
• 450 mg: −57.1% (P < .05)
• 300 mg: −64.3% (P < .01)
• Placebo: −41.7%

Investigators pointed out improvements emerged as early as week 1 with the 450 mg (−22.3%; P < .01) and 300 mg (−19.6%; P < .05) doses, and by week 2 with the 600 mg arm (−35.0%; P < .05), while placebo achieved −8.0% at week 1 and −22.7% at week 2. Efficacy was maintained through week 32 in the 600 mg (−59.1%; P < .05) and 300 mg (−60.6%; P < .05) cohorts, despite no treatment beyond week 14.

In a companion presentation, investigators shared results from a biomarker analysis of the phase 2b trial. Among 22 patients randomized to temtokibart, gene expression data from 14 patients out to 16 weeks revealed a 97% improvement in immune gene expression and significant restoration of epidermal barrier–related genes. Reductions in EASI and SCORAD scores correlated with decreases in Th2 and Th17/22 markers (P ≤ .05), while improvements in DLQI and POEM correlated with reductions in key T-cell and inflammatory markers.

For more on the results of this study and how it informs the potential of temtokibart in atopic dermatitis, check out our interview with Weidinger from the conference floor at EADV 2025.

Relevant disclosures for Weidinger include AbbVie, Almirall, Galderma, Kymab, LEO Pharma, Eli Lilly and Company, Pfizer, Regeneron, La Roche Posay, and Sanofi.

References:

1. Leo Pharma. LEO Pharma presents two late-breaking abstracts for temtokibart reporting positive Phase 2b efficacy, safety and biomarker results in moderate-to-severe atopic dermatitis at the 2025 EADV Annual Meeting in Paris. Leo-pharma.com. Published September 17, 2025. Accessed September 18, 2025. https://www.leo-pharma.com/media-center/news/2025-temtokibart-late-breaker-press-release

2. Weidinger S. IL-22RA1 antagonism with temtokibart provides significant early and sustained improvements in atopic dermatitis: results from a phase 2b dose-finding trial. Presented at the European Association of Dermatology and Venereology (EADV) 2025 Congress. Paris, France. September 17-20, 2025.

3. Del Duca, E. Temtokibart, an IL-22RA1 Monoclonal Antibody broadly dampens gene expression markers of activated immune pathways in Atopic Dermatitis: Results from a Phase 2b Trial Subgroup Analysis. Presented at the European Association of Dermatology and Venereology (EADV) 2025 Congress. Paris, France. September 17-20, 2025.