Mercury Chelation to Treat Autism
|First Received Date ICMJE||September 13, 2006|
|Last Updated Date||September 17, 2013|
|Start Date ICMJE||September 2006|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE
||Improvement in social reciprocity.|
|Original Primary Outcome Measures ICMJE||Same as current|
|Change History||Complete list of historical versions of study NCT00376194 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE
||Improvement in language skills, decrease in blood mercury levels.|
|Original Secondary Outcome Measures ICMJE||Same as current|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Mercury Chelation to Treat Autism|
|Official Title ICMJE||An Investigation of the Efficacy of Mercury Chelation as a Treatment for Autism Spectrum Disorder|
This study will examine whether DMSA, an oral chelating agent that removes mercury and other metals from the body, is beneficial for children with autism. DMSA is commonly used to treat autism, although it has never been tested in a controlled study and there is no proof that it helps children with the disorder. Support for its use is based on single-case reports of benefits of chelation with DMSA. This study will help determine whether or not DMSA is useful for treating autism.
Children between 4 and 10 years of age with autism spectrum disorder who weigh at least 33 pounds, who have detectable, but not toxic, levels of mercury or lead in the blood, and who have not previously received chelation therapy may be eligible for this study.
Participants complete a medical history, behavioral and psychological assessment and physical examination. Blood, hair, urine and stool samples are collected for testing.
Because DMSA can remove minerals the body needs, such as zinc and iron, as well as the toxic lead and mercury, participants take a daily multivitamin supplement starting 1 month before beginning chelation therapy and continuing for the duration of treatment. After 1 month of the supplementation regimen, the children are assigned to receive DMSA or placebo for 12 weeks, divided into six 2-week cycles. They take the assigned drug 3 times a day on days 1, 2 and 3 of each cycle and continue the multivitamin every day.
The children are seen in the clinic immediately before and after the first, third and sixth cycles. At each checkup, the parent or guardian answers a set of questions about the child's autism symptoms, physical health and medication side effects. Blood, urine and stool samples are collected for laboratory testing.
Chelation of metals is widely used in the community to treat individuals with Autism Spectrum Disorder (ASD), with some surveys estimating that 1 in 12 children with autism have undergone chelation. This widespread use reflects the hypothesis that many cases of ASD are caused by exposure to thimerosal, an ethylmercury-based compound used previously in the US as a vaccine preservative for routine childhood immunizations. The prevalent use of chelation therapy stands in stark contrast with the lack of scientific or clinical evidence of efficacy, and creates a public health imperative for empiric data. Thus we propose a controlled trial of the effects of chelation on the core behavioral symptoms and overall functioning of children with ASD. The present investigation is a double-blind, randomized placebo-controlled study of the oral chelating agent meso-2,3-dimercaptosuccinic acid (DMSA; succimer) among 120 children, ages four to ten years, who meet criteria for ASD. Pre- and post-treatment behavioral ratings will be used to evaluate the efficacy of chelation. In addition, children will undergo comprehensive medical history, physical examination and laboratory analyses.
Our objective is to quantify differences in behavioral functioning between the chelation treatment group and the placebo control group. Analysis of mercury levels before and during the course of treatment will be used to confirm the expected DMSA-induced excretion of mercury and to identify differences among children in the extent of excretion. Our primary hypothesis is that, on average and relative to the control group, children with ASD who undergo chelation with DMSA will show greater improvements in communication and social behavior.
|Study Type ICMJE||Interventional|
|Study Phase||Phase 2|
|Study Design ICMJE||Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Primary Purpose: Treatment
|Intervention ICMJE||Drug: DMSA|
|Study Arm (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Withdrawn|
|Completion Date||March 2007|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Subjects may be included in the study only if they meet all of the following criteria:
|Ages||4 Years to 10 Years|
|Accepts Healthy Volunteers||No|
|Contacts ICMJE||Contact information is only displayed when the study is recruiting subjects|
|Listed Location Countries ICMJE||United States|
|Removed Location Countries|
|NCT Number ICMJE||NCT00376194|
|Other Study ID Numbers ICMJE||060238, 06-M-0238|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Institute of Mental Health (NIMH)|
|Collaborators ICMJE||Not Provided|
|Investigators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||September 2013|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP