By Fineline Cube 
Jiangsu Hengrui Pharmaceuticals Co., Ltd. (SHA: 600276, HKG: 1276) announced that its proprietary topical RSS0393 ointment has received approval from the National Medical Products Administration (NMPA) to initiate a clinical trial for the treatment of atopic dermatitis (AD).
Product Overview
- Mechanism of Action – RSS0393 is a small‑molecule phosphodiesterase‑4 (PDE4) inhibitor that blocks PDE4 activity in keratinocytes, T cells, and mast cells.
- Therapeutic Effect – Inhibition of PDE4 elevates intracellular cAMP, leading to reduced pro‑inflammatory cytokine release, diminished skin inflammation, and attenuation of tissue damage.
Regulatory Milestone
| Authority | Approval | Study Phase | Indication |
|---|---|---|---|
| NMPA | 4 Sep 2025 | Phase I/II (clinical trial) | Atopic dermatitis |
- First time Hengrui’s topical PDE4 product receives NMPA trial authorization.
- Positions the company to enter a growing AD market that is currently dominated by corticosteroids and calcineurin inhibitors.
Market Context
- AD Prevalence – ~10 % of the global population; China alone accounts for ~70 M affected individuals.
- Competitive Landscape – FDA‑approved PDE4 inhibitors (e.g., crisaborole) and biologics are emerging, but no Chinese‑origin topical PDE4 therapy has reached clinical testing.
- Commercial Potential – Successful trials could unlock a multi‑billion‑dollar pipeline in skin‑care therapeutics, especially given rising consumer demand for non‑steroidal options.-Fineline Info & Tech