Study on Tolerability of Levodopa/Carbidopa in Children With Angelman Syndrome

A Dose-escalation Tolerability Study of Levodopa/Carbidopa in Angelman Syndrome

This study is designed to determine the highest dose of levodopa/carbidopa that can be tolerated without any serious side effects by children with Angelman syndrome.

It has been hypothesized that levodopa may lead to an improvement in the neurodevelopment and abnormal movements (e.g. tremors) in children with Angelman syndrome.

Data from this study will be used to design a phase II trial to determine the efficacy of levodopa in treating children with Angelman syndrome.

Study Overview

• Status: Completed
• Conditions: Angelman Syndrome
• Intervention / Treatment: Drug: Levodopa/Carbidopa (4:1)

Detailed Description

Levodopa is a prodrug that "delivers" dopamine to the brain. It is usually given with carbidopa, a peripheral decarboxylase inhibitor, to increase the bioavailability of levodopa. Animal studies have suggested that levodopa can reverse the excess phosphorylation of some enzymes involved in synaptic and neuronal function, including calcium/calmodulin-dependent kinase type 2 (CaMKII).

Recently, it was shown that excess phosphorylation of CaMKII may be responsible for some of the neurological deficits seen in Angelman syndrome. Therefore, it is hypothesized that levodopa may lead to an improvement in the neurodevelopment and abnormal movements (e.g. tremors) in children with Angelman syndrome.

Although many children have used levodopa for a variety of medical conditions over the last 30 years, it has not been approved by the Food and Drug Administration (FDA) for use in children, and it has not been formally studied in children with Angelman syndrome, so we do not know what dose of levodopa is most appropriate for children with Angelman syndrome.

Therefore, the purpose of this study is to find out the highest dose of levodopa that children with Angelman syndrome can tolerate without any serious side effects.

Once we know the dose of levodopa that can be tolerated by children with Angelman syndrome, we will conduct a larger follow-up study to find out whether levodopa will lead to an improvement in their development and tremor.

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Children's Hospital Boston

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 4 years to 12 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Angelman syndrome, confirmed by molecular testing
• Must be willing to come for research visit on 2 days, exactly 1 week apart

Exclusion Criteria:

• On levodopa, carbidopa, or any dopamine agonists in the 2 weeks prior to participation
• Other medical conditions that may be associated with developmental or cognitive delays
• More than 2 clinical seizures per month
• Used monoamine oxidase (MAO) inhibitors within the last 2 weeks
• Used phenytoin within the last 2 weeks
• Used phenothiazines, butyrophenones, and thioxanthenes within last 2 weeks
• Hypersensitive to levodopa or carbidopa
• Cardiovascular disease or instability
• Respiratory diseases, including asthma, emphysema, chronic cough, and shortness of breath
• Liver disease
• Stomach or intestinal ulcers
• Kidney disease
• Hematological problems, including anemia, leucopenia, and thrombocytopenia
• Used investigational drugs/interventions within the past three months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Levodopa/Carbidopa; Other Names: Sinemet L-dopa Dosages are based on levodopa. Each cohort of 3 subjects will be placed on an increasing dose of levodopa (2, 5, 10, and 15 mg/kg/day) for 1 week, provided subjects in the preceding cohort tolerated the lower dose. Levodopa/Carbidopa is a combined formulation that will be dispensed as capsules. It should be taken 3 times a day.	Drug: Levodopa/Carbidopa (4:1); Dosages are based on levodopa. Each cohort of 3 subjects will be placed on an increasing dose of levodopa (2, 5, 10, and 15 mg/kg/day) for 1 week, provided subjects in the preceding cohort tolerated the lower dose. Levodopa/Carbidopa is a combined formulation that will be dispensed as capsules. It should be taken 3 times a day.; Other Names: Sinemet; L-dopa

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Maximum Dose of Levodopa/Carbidopa That Can be Tolerated (Without Any Dose Limiting Toxicity) by at Least 3 Subjects.	1 week

Collaborators and Investigators

• Sponsor: Boston Children's Hospital

Study record dates

Study Major Dates

• Study Start: January 1, 2009
• Primary Completion (Actual): June 1, 2010
• Study Completion (Actual): June 1, 2010

Study Registration Dates

• First Submitted: January 26, 2009
• First Submitted That Met QC Criteria: January 26, 2009
• First Posted (Estimate): January 27, 2009

Study Record Updates

• Last Update Posted (Estimate): November 21, 2016
• Last Update Submitted That Met QC Criteria: September 29, 2016
• Last Verified: September 1, 2016

More Information

Terms related to this study

• Keywords: Angelman syndrome; Levodopa; Carbidopa; L-dopa
• Additional Relevant MeSH Terms: Pathologic Processes; Central Nervous System Diseases; Nervous System Diseases; Disease; Congenital Abnormalities; Genetic Diseases, Inborn; Movement Disorders; Abnormalities, Multiple; Chromosome Disorders; Syndrome; Angelman Syndrome; Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Dopamine Agents; Antiparkinson Agents; Anti-Dyskinesia Agents; Aromatic Amino Acid Decarboxylase Inhibitors; Levodopa; Carbidopa
• Other Study ID Numbers: 08-10-0490

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Undecided

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No