LEO Pharma, a Danish drugmaker, disclosed on Tuesday that it has reached an agreement to obtain worldwide rights to the experimental oral therapy dersimelagon from Japan’s Tanabe Pharma. The transaction includes up‑front payments and near‑term milestone payments that could total as much as $435 million.

Strategic expansion into rare‑disease treatments

The acquisition aligns with LEO Pharma’s broader strategy to grow its portfolio in the rare‑genetic‑skin‑disease market. The company previously partnered with Boehringer Ingelheim on the drug Spevigo in July 2025 and purchased U.S. developer Replay in April.

Dersimelagon is being developed for erythropoietic protoporphyria (EPP) and X‑linked protoporphyria (XLP), two rare inherited conditions that cause extreme sensitivity to sunlight. By increasing melanin production, the drug aims to protect patients from painful light‑induced reactions. If approved, it would be the first oral therapy for these diseases.

Potential market and regulatory timeline

LEO Pharma CEO Christophe Bourdon told Reuters that the unmet need in EPP is significant, estimating roughly 5,000 affected patients in the United States alone. He added that the U.S. Food and Drug Administration could grant approval as early as 2027, and LEO intends to launch the product without delay once clearance is received.

The agreement also provides for downstream milestone payments and tiered royalties on net sales, further tying the companies’ financial interests to the drug’s commercial success.

Implications for LEO Pharma

Securing the rights to dersimelagon adds a promising growth driver as LEO Pharma explores a potential stock‑market listing. The deal underscores the firm’s commitment to expanding its rare‑disease pipeline and diversifying its revenue base beyond its existing dermatology and wound‑care offerings.

Original reporting: Appleton, WI News Feed (HLL/CB) — read the source article.