Last reviewed 2026-04-23 · How we verify

OPA-15406

OPA-15406 is a selective JAK1 inhibitor that reduces inflammatory signaling to treat immune-mediated skin diseases.

OPA-15406 is a selective JAK1 inhibitor that reduces inflammatory signaling to treat immune-mediated skin diseases. Used for Atopic dermatitis, Other inflammatory skin conditions.

At a glance

Mechanism of action

OPA-15406 selectively inhibits Janus kinase 1 (JAK1), a key enzyme in the JAK-STAT signaling pathway that drives inflammatory and immune responses. By blocking JAK1, the drug suppresses the production of pro-inflammatory cytokines and reduces pathogenic T-cell activation, thereby ameliorating symptoms in conditions like atopic dermatitis and other inflammatory skin disorders.

Approved indications

• Atopic dermatitis
• Other inflammatory skin conditions

Common side effects

• Nasopharyngitis
• Upper respiratory tract infection
• Headache
• Application site reactions

Key clinical trials

• A Phase 3 Trial of OPA-15406 Foam in Children and Infants With Atopic Dermatitis (PHASE3)
• A Phase 3 Trial to Demonstrate the Superiority of 1% OPA-15406 Foam to the Vehicle in Adult Patients With Atopic Dermatitis (PHASE3)
• To Demonstrate the Superiority of IMP (1% OPA-15406 Ointment) to the Vehicle in Adult Patients With AD (PHASE3)
• A Long-term Trial of OPA-15406 in Infants With Atopic Dermatitis (PHASE3)
• To Demonstrate the Superiority of IMP (0.3% and 1% OPA-15406 Ointment) Versus the Vehicle in Pediatric Patients with AD (PHASE3)
• A Study to Evaluate the Effectiveness and Safety of Topical OPA-15406 Ointment to Treat Participants With Atopic Dermatitis (PHASE2)
• Long-term Trial of OPA-15406 Ointment in Adult and Pediatric Patients With Atopic Dermatitis (PHASE3)
• Comparison Trial of OPA-15406 Ointment in Pediatric Patients With Atopic Dermatitis (PHASE3)

Primary sources

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