Last reviewed 2026-04-23 · How we verify

TP05

TP05 is a topical phosphodiesterase 4 (PD4) inhibitor that reduces inflammatory cytokine production in skin.

TP05 is a topical phosphodiesterase 4 (PD4) inhibitor that reduces inflammatory cytokine production in skin. Used for Atopic dermatitis, Psoriasis.

At a glance

Mechanism of action

TP05 inhibits phosphodiesterase 4 enzyme activity in immune and inflammatory cells, leading to decreased production of pro-inflammatory mediators such as TNF-α and IL-23. This mechanism reduces skin inflammation and is intended for treatment of inflammatory skin conditions.

Approved indications

• Atopic dermatitis
• Psoriasis

Common side effects

• Application site irritation
• Headache
• Nausea

Key clinical trials

• A Human Tick Kill Study to Investigate the Safety, Tolerability, and Whole Blood Concentration of TP-05 (PHASE2)
• Study to Evaluate the Food Effect of TP-05 in Healthy Participants (PHASE1)
• A Pharmacokinetic Study of TP-05 in Healthy Subjects (PHASE1)
• TP05 for the Treatment of Mild to Moderate Active Ulcerative Colitis (UC) (PHASE3)
• TP0502-B-Pharmaco-Scintigraphic-Study (PHASE1)
• TP0502-Pharmaco-Scintigraphic-Study and Amendment (PHASE1)
• TP0501 - Pharmaco-Scintigraphic-Study (PHASE1)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• TP05 CI brief — competitive landscape report
• TP05 updates RSS · CI watch RSS
• Tillotts Pharma AG portfolio CI