The EXCEL Study

• Research type

  Research Study

• Full title

  A Non-interventional, Epidemiologic Study of XLMTM and Clinical Expression in the Liver

• IRAS ID

  359364

• Contact name

  Giovanni Baranello

• Contact email

  g.baranello@ucl.ac.uk

• Sponsor organisation

  Astellas Gene Therapies

• Clinicaltrials.gov Identifier

  06581146, NCT Number

• Duration of Study in the UK

  1 years, 6 months, 17 days

• Research summary

  X-linked myotubular myopathy (XLMTM) is a rare genetic disorder that primarily affects muscle strength and function in participants and can cause muscle weakness, difficulties in breathing, and developmental delays. Liver problems have also been identified in some individuals with XLMTM. The aim of this study is to find out how often people living with XLMTM experience problems related to blocked or reduced bile flow in the liver (cholestatic complications), and to collect information that can help to improve current treatment practices, management of XLMTM, and future potential clinical study designs for investigational treatments. This study is a real-world clinical study (an observational study) to better understand liver problems in male participants with XLMTM and it will not involve the testing of investigational medicines or therapies.
  Participants will be in this study for up to 48 weeks (approximately 1 year) from the moment they consent to participate.
  Around 50 male participants who are < 18 years of age will take part in this study in Canada (CAN), the United Kingdom (UK), and the United States (US).
  The primary objective is to assess hepatobiliary health by estimating the incidence and prevalence of cholestatic complications in participants with XLMTM.
  The secondary objectives are:
  ● To evaluate the association between genetic variants of MTM1 and cholestasis
  ● To evaluate the association between environmental modifiers and cholestasis
  ● To evaluate healthcare utilisation related to hepatobiliary and cholestatic complications

• REC name

  East of England - Essex Research Ethics Committee

• REC reference

  25/EE/0157

• Date of REC Opinion

  29 Sep 2025

• REC opinion

  Further Information Favourable Opinion