The US Food and Drug Administration (FDA) has approved Mirum Pharmaceuticals’ Ctexli (chenodiol) for the treatment of cerebrotendinous xanthomatosis (CTX) in adults.
Ctexli is the first FDA-approved medication for this rare lipid storage disease.
The recommended dosage of Ctexli is 250 mg, taken orally three times a day.
Mirum Pharmaceuticals gained access to the oral drug through its $445m acquisition of Travere Therapeutics’ bile acid product portfolio in 2023.
In June 2024, the biopharmaceutical company submitted a new drug application (NDA) for chenodiol to the FDA for the treatment of CTX patients.
The approval was based on results from a 24-week, double-blind, placebo-controlled, randomised RESTORE trial.
The study assessed Ctexli’s efficacy in treating CTX in adult patients.
According to the results, the RESTORE trial achieved its primary endpoint, showing a significant reduction in bile alcohols.
Patients taking 250 mg of Ctexli three times daily had significant reductions in plasma cholestanol and urine 23S-pentol, both key cholesterol metabolites elevated in CTX, compared to the placebo.
Additionally, the study showed that treatment with chenodiol significantly improved serum cholestanol.
The most common side-effects of Ctexli include abdominal pain, diarrhoea, headache, constipation, muscular weakness, hypertension, and upper respiratory tract infections.
FDA Center for Drug Evaluation and Research Pediatrics, Urologic and Reproductive Medicine Office of Rare Diseases director Janet Maynard said: “The FDA is dedicated to supporting new drug development for rare diseases including very rare metabolic diseases like cerebrotendinous xanthomatosis.
“CTX is a progressive multisystemic disorder that significantly impacts patients and previously lacked approved treatments. Today’s approval provides a safe and effective treatment option for CTX.”
CTX is a genetic disorder caused by a mutation in the CYP27A1 gene, leading to impaired fat breakdown and abnormal cholesterol deposits in organs like the brain and liver.
Ctexli helps by replacing a deficient bile acid, reducing harmful cholesterol buildup in CTX patients.
