Tanabe Pharma America Announces Positive Topline Results for Dersimelagon in Erythropoietic Protoporphyria (EPP) and X-Linked Protoporphyria (XLP)

JERSEY CITY, N.J., Jan. 20, 2026 /PRNewswire/ -- Tanabe Pharma America, Inc., the wholly owned subsidiary of Tanabe Pharma Corporation, today announced positive topline efficacy and safety results from the global Phase 3 clinical trial, also known as the INSPIRE study, of investigational dersimelagon (MT-7117), a selective melanocortin-1 receptor (MC1R) agonist, being developed for the oral treatment of adult and adolescent patients with erythropoietic protoporphyria (EPP) and X-linked protoporphyria (XLP).

EPP and XLP are rare hereditary disorders of the heme biosynthetic pathway that are characterized by severe pain in the skin upon exposure to sunlight and some forms of artificial light. It is estimated that approximately 1 in 75,000 to 1 in 200,000 individuals have EPP in the European population, though the prevalence in the US is not known.

"The limited treatment options for adults with EPP or XLP and lack of any approved treatments for adolescents have created a care deficit, forcing many to endure severe life disruptions as they rely only on sun protection or avoidance," said Bijan Nejadnik, Head of Global Development and Regulatory Affairs. "The positive topline results from the INSPIRE study represent key data that will guide our research for the porphyria community."

The INSPIRE study is a global, randomized, double-blind, placebo-controlled Phase 3 clinical trial investigating the efficacy, safety, and tolerability of dersimelagon in adult and adolescent patients with EPP or XLP. The study consists of a 16-week double-blind treatment period, in which participants are randomly assigned to either the placebo group or active treatment group (dersimelagon 200 mg once daily), followed by a 36-week open-label extension period of active treatment. The study met the primary endpoint, which is the time to first prodromal symptoms (such as burning, tingling, itching, or stinging) associated with sunlight exposure. In the INSPIRE study, dersimelagon demonstrated a favorable safety and tolerability profile, with most adverse events being mild or moderate in severity. The open-label extension period is ongoing.

Tanabe Pharma America is committed to evaluating innovative products to market for patient populations with unmet needs. Dersimelagon is an investigational medication that received Fast Track Designation from the U.S. FDA in June 2018 and was granted Orphan Drug Designation in June 2020. Dersimelagon has not been approved by the FDA or any other regulatory agency.

About Erythropoietic Protoporphyria and X-Linked Protoporphyria
Erythropoietic protoporphyria (EPP) is an inherited disorder of the heme biosynthetic pathway that results from partial deficiency of the enzyme ferrochelatase (FECH), which results from (mutations) in the FECH gene. X-linked protoporphyria (XLP) is a less common type of EPP that results from gain-of-function mutations in the aminolevulinic acid synthase-2 (ALAS2) gene. Both EPP and XLP are characterized by accumulation of protoporphyrin in blood, erythrocytes, and tissues and cutaneous photosensitivity. EPP and XLP usually present early in childhood with extremely painful phototoxic reactions which are preceded by a "prodrome" of tingling, stinging, and/or burning of sun-exposed skin. The onset of prodromal symptoms after direct sun exposure varies but may occur in less than 10 minutes. Importantly, continued exposure to sunlight following the onset of prodromal symptoms will lead to phototoxicity-induced pain.

About INSPIRE Study
INSPIRE is a global, randomized, double-blind, placebo-controlled Phase 3 study investigating the efficacy, safety, and tolerability of dersimelagon (MT-7117) in 165 adults and adolescents with erythropoietic protoporphyria (EPP) or X-linked protoporphyria (XLP). After screening, study participants (ranging from 12 to 75 years of age) received either dersimelagon 200 mg or placebo once daily. The primary endpoint was change from baseline in average daily sunlight exposure time (in minutes) to first prodromal symptom (burning, tingling, itching, stinging) associated with sunlight exposure between 1-hour post-sunrise and 1-hour pre-sunset at week 16. Secondary endpoints were patient Global Impression of Change (PGIC) at week 16, the total number of sunlight-induced pain events defined as prodromal symptoms with pain rating of 1-10 on the Likert scale during the 16-week double-blind treatment period, and the total number of sunlight-induced non-prodrome, phototoxic reactions during the 16-week double-blind treatment period.

About Dersimelagon (MT-7117)
Dersimelagon is a novel synthetic, orally administered, non-peptide small molecule, which acts as a selective agonist of melanocortin-1 receptor (MC1R) to increase melanin production with a potential for being effective to increase pain free light exposure in patients with a history of phototoxicity from erythropoietic protoporphyria (EPP) or X-linked protoporphyria (XLP). Tanabe Pharma Corporation is evaluating dersimelagon as a potential treatment option for EPP or XLP.

About Tanabe Pharma America, Inc.
Based in Jersey City, N.J., Tanabe Pharma America, Inc. is a wholly-owned subsidiary of Tanabe Pharma Corporation. It was established by Tanabe Pharma to develop and advance our pipeline as well as commercialize approved pharmaceutical products in North America. For more information, please visit us.tanabe-pharma.com or follow us on X (formerly Twitter), Facebook and LinkedIn.

About Tanabe Pharma Corporation, Inc.
Tanabe Pharma Corporation is one of the oldest pharmaceutical companies in the world, founded in 1678. Tanabe Pharma is headquartered in Doshomachi, Osaka, the birthplace of Japan's pharmaceutical industry. Tanabe Pharma sets the MISSION of "Creating hope for all facing illness." To that end, Tanabe Pharma is working on the disease areas of central nervous system, immuno-inflammation, diabetes and kidney, and cancer. Tanabe Pharma is focusing on "precision medicine" to provide drugs with high treatment satisfaction and additionally working to develop "around the pill solutions" to address specific patient concerns based on therapeutic medicine, including prevention of diseases, pre-symptomatic disease care, prevention of aggravation and prognosis. For more information, go to https://www.tanabe-pharma.co.jp/e/.

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SOURCE Tanabe Pharma America