R&D in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by intense pruritus and substantially reduced quality of life. Drug discovery for AD remains a priority, with numerous programs over the years. Antibody therapies and small-molecule agents have been developed, and each has demonstrated efficacy in improving AD symptoms. Nonclinical studies are essential to these discovery efforts.

Case Study: Kyoto University Graduate School of Medicine

Dr. Kenji Kabashima, Kyoto University Graduate School of Medicine, is a member of theFocus on a compound called Janus kinase (JAK)Kenji Kabashima, M.D., Ph.D. (Kyoto University Graduate School of Medicine) focused on the Janus kinase (JAK) pathway and JAK inhibitors. Although JAK inhibitors were initially investigated as oral therapies for rheumatoid arthritis, they were found to improve skin-barrier function. Due to concerns about systemic adverse effects with oral administration, development proceeded with a topical formulation, resulting in the nonsteroidal topical agent delgocitinib (Corectim Ointment).

Nonclinical Studies

In this development, experiments were conducted using a mouse model; mice treated with the JAK inhibitor had their skin barrier function restored and their atopic dermatitis symptoms improved. The results of this animal study accelerated the development of a new drug,In addition to its anti-inflammatory action, it was also found to improve skin rashes by reducing itching

Development Case Study: Chugai Pharmaceutical Co., Ltd.

Chugai Pharmaceutical Co., Ltd., in joint development with Galderma—the exclusive licensee for nemolizumab—reported positive results in Phase 3 clinical trials (ARCADIA-1, ARCADIA-2, and OLYMPIA-1). Across these studies, nemolizumab produced statistically significant reductions in skin lesions and pruritus in patients with atopic dermatitis, and early, clinically meaningful improvement in pruritus was reported.

Nonclinical Studies

Prior to the Phase 3 trials, multiple nonclinical studies were conducted in support of nemolizumab’s development. These studies demonstrated activity in preclinical models and supported efficacy ahead of clinical evaluation.

Phase 3 Clinical Results (OLYMPIA-1) In OLYMPIA-1, where nemolizumab was administered as monotherapy, pruritus and skin lesions were significantly reduced versus placebo. At Week 16, two primary endpoints showed clinically and statistically significant improvement compared with placebo; these findings were confirmed independently of the Phase 3 OLYMPIA-2 results.

Summary

New drug development is essential for the treatment of atopic dermatitis. Many examples have been successful, such as delgocitinib, a JAK inhibitor developed by Kyoto University Graduate School of Medicine, and nemolizumab developed by Chugai Pharmaceutical Co. Non-clinical studies have played an important role in these drug discoveries,Experiments using animal models, etc. are effectively utilized.. It is hoped that through the process of new drug development, more effective treatments will be provided.