FDA

First treatment for cerebrotendinous xantomatosis approved

March 5, 2025

Brand name: Ctexli

Generic name: chenodiol

Manufacturer: Murim Pharmaceuticals

Approval date: February 21, 2025

FDA approved Ctexli (chenodiol) for the treatment of cerebrotendinous xanthomatosis (CTX) in adults.

CTX is a genetic metabolic disorder caused by a mutation in the CYP27A1 gene resulting in a deficiency of the enzyme that breaks down fats. Due to reduced bile acid production in the liver, patients with CTX are unable to break down cholesterol, resulting in deposition of atypical cholesterol metabolites in various places in the body including the brain, liver, skin and tendons, leading to tissue and organ damage. Ctexli works by replacing deficient levels of one of the bile acids, reducing the abnormal deposits of cholesterol metabolites thought to be responsible for clinical abnormalities in CTX.

Efficacy

Approval was based on data from a double-blind, placebo controlled, randomized crossover withdrawal trial (RESTORE; NCT04270682). The 24-week trial demonstrated that treatment with Ctexli, 250 mg tid, resulted in significant reduction in plasma cholestanol and urine 23S-pentol (cholesterol metabolites that are markedly increased in CTX patients) compared with placebo.

Safety

The prescribing information for Ctexli includes a warning for liver toxicity in all patients, with increased risk for liver damage in patients with pre-existing liver disease or bile duct abnormalities. Liver function tests are recommended before starting treatment, annually while on treatment, and as clinically indicated. If signs of liver toxicity (e.g., stomach pain, nausea, fatigue, dark urine, bruising, jaundice, itching) occur, patients are advised to see their doctor and discontinue Ctexli.

The most common adverse effects of Ctexli include diarrhea, headache, abdominal pain, constipation, hypertension, muscular weakness, and upper respiratory tract infection.

Recommended dose

The recommended dosage of Ctexli is 250 mg PO tid.

Sources:

FDA approves first treatment for cerebrotendinous xanthomatosis, a rare lipid storage disease. Food and Drug Administration. 2025. https://www.fda.gov/news-events/press-announcements/fda-approves-first-treatment-cerebrotendinous-xanthomatosis-rare-lipid-storage-disease

Mirum’s CTEXLI™ (chenodiol) Tablets Receives FDA Approval for Treatment of Cerebrotendinous Xanthomatosis (CTX). Mirum Pharmaceuticals. 2025. https://ir.mirumpharma.com/news-events/News/news-details/2025/Mirums-CTEXLI-chenodiol-Tablets-Receives-FDA-Approval-for-Treatment-of-Cerebrotendinous-Xanthomatosis-CTX/default.aspx

Ctexli. Package insert. Mirum Pharmaceuticals. 2025. https://www.accessdata.fda.gov/drugsatfda_docs/label/2025/219488s000lbl.pdf