Tanabe Pharma’s Dersimelagon Meets Phase III Endpoint in EPP and XLP

Tanabe Pharma America’s oral MC1R agonist, dersimelagon, met the primary endpoint in its Phase III INSPIRE trial for erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP). The study of 165 patients showed a significant improvement in time to first prodromal symptoms—burning, tingling, itching, or stinging triggered by sunlight.

The 16-week double-blind trial compared dersimelagon 200mg daily with placebo, followed by a 36-week open-label extension. Secondary endpoints included patient-reported Global Impression of Change, total sunlight-induced pain events, and phototoxic reactions. Dersimelagon demonstrated a favorable safety profile, with most adverse events mild or moderate.

EPP and XLP are rare hereditary disorders causing severe photosensitivity, with few treatment options. The FDA has granted Fast Track and Orphan Drug designations for dersimelagon. Tanabe Pharma could gain a first-to-market advantage over competitors like Disc Medicine, which is testing bitopertin in Phase III trials.

20-01-2026