MVX-220 gene therapy for Angelman syndrome

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This Phase 1/2 trial gives a single intracisternal dose of MVX-220, an AAV-based UBE3A gene replacement, to cohorts of adults followed by children with confirmed deletion, uniparental disomy, or imprinting center defects. There is no control group; all participants receive the gene therapy and an independent data safety monitoring board reviews adult safety before pediatric enrollment. Participants receive short-course steroids to reduce immune reactions and must be ambulatory and on stable antiepileptic medication at enrollment. Safety and effectiveness are monitored closely for two years after dosing and then with less frequent visits for a total five-year follow-up.

Why it matters

Who can join: the full rules

Key Inclusion Criteria:

1. The participant's parent/legal guardian must provide written informed consent.
2. Symptoms consistent with AS and documented genetic confirmation of one of the following genotypes resulting in a diagnosis of AS:

   1. Full maternal UBE3A gene deletion causing AS in the region of 15q11.2-q13
   2. Uniparental disomy
   3. Imprinting center defect
3. The participant must be 18 to 50 years of age, inclusive (for adult participants), or 4 to 8 years of age, inclusive (for pediatric participants), at Screening.
4. The participant must have the ability to ambulate independently.
5. The participant must be on stable antiepileptic medications (with no changes within 1 month prior to the Screening visit, except for weight associated dose adjustments).

Key Exclusion Criteria:

1. Clinically significant medical finding other than AS, that, in the judgment of the Investigator would make the participant unsuitable for participation.
2. Laboratory abnormalities including but not limited to:

   1. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \> upper limit of normal (ULN)
   2. Total and/or fractionated bilirubin (direct and/or indirect) \> ULN
   3. Gamma-glutamyl transferase (GGT) \> ULN
   4. Estimated glomerular filtration rate (eGFR) below the lower limit of normal (LLN) for age
   5. Hemoglobin \< 8 g/dL
   6. White blood cell (WBC) count outside the normal range for age
   7. Platelet count \< LLN
   8. Partial thromboplastin time (PTT) outside the reference range
   9. PT/International normalized ratio (INR) outside the reference range
3. Any known history and/or family history of hemophagocytic lymphohistiocytosis (HLH)/macrophage activation syndrome (MAS) or multisystem inflammatory syndrome (MIS).
4. Any known history and/or family history of disordered complement function and/or complement gene mutation(s).
5. History of systemic lupus erythematous, Still's disease, rheumatoid arthritis, and/or other severe autoimmune conditions per judgment of the Investigator.
6. Any known history of thrombotic microangiopathy (TMA)/microangiopathic hemolytic anemia, or hypercoagulable conditions including, but not limited to, disseminated intravascular coagulation (DIC), deep venous thrombosis, and pulmonary embolism.
7. Current therapy with high dose immunosuppressants.
8. Prior or current treatment with an investigational drug within 6 months or 5-half-lives of the hospital admission whichever is longer.
9. Prior treatment with an antisense oligonucleotide within 1 year of hospital admission.
10. A history of gene therapy administration.
11. Any contraindication to ICM administration procedure, including contraindications to imaging, contrast use, anesthesia, or any condition that would increase the risk of adverse outcomes from the ICM procedure.
12. Any contraindication to glucocorticoid use

Where it's running

• Cedars-Sinai Medical Center
  Los Angeles, California, United States Recruiting
• Rush University Medical Center
  Chicago, Illinois, United States Recruiting
• Boston Children's Hospital
  Boston, Massachusetts, United States Recruiting

Study contacts

• Study coordinator: MavriX Bio, LLC
• Email: info@mvxbio.com
• Phone: 978-538-8554

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• Obudanersen for Angelman Syndrome in UPD/ID patients

  This study tests obudanersen in children and adults with Angelman syndrome caused by UPD or imprinting defects to see if it improves expressive communication.

  Recruiting Phase 3 Ionis Pharmaceuticals, Inc. · Carrboro, North Carolina · NCT07782827

• Rugonersen in Angelman Syndrome (phase 3)

  This trial tests whether rugonersen given into the spine can help people with Angelman syndrome, compared with a sham procedure.

  Recruiting at 10 sites Phase 3 OHB Pediatrics Ltd. · Los Angeles, California and 9 other locations · NCT07605429

• Tracking changes in Angelman syndrome over 12 months

  This study will see how developmental skills, behavior, sleep, and brain activity change over one year in children and adults with a genetically confirmed diagnosis of Angelman syndrome.

  Recruiting Massachusetts General Hospital · Lexington, Massachusetts · NCT07417137

• Using eye tracking to understand social perception in children with Angelman syndrome

  This study is testing how children with Angelman syndrome see and understand social situations compared to healthy kids, using eye tracking technology to help find ways to measure their progress in future treatments.

  Recruiting Assistance Publique - Hôpitaux de Paris · Paris · NCT06737718

• Understanding brain connectivity in drug-resistant epilepsy and neurodevelopmental syndromes

  This study is testing how the brain connects in people with drug-resistant epilepsy and certain developmental disorders to see if it can help improve their treatment options.

  Recruiting IRCCS Eugenio Medea · Conegliano, Treviso · NCT06353620

• Natural history observation for Angelman syndrome patients

  This study is trying to learn more about how Angelman syndrome affects patients over nine years by regularly checking their motor skills, thinking abilities, and quality of life.

  Recruiting Centre Hospitalier Universitaire de Liege · Liège, Liège · NCT06229769

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.