the 4-center, placebo-controlled
randomized clinical trial of succimer
for the prevention of lead-induced alterations
in growth, behavior & development in toddlers
sponsored by the
National Institute of Environmental Health Sciences
with support from the
Office of Research on Minority Health
National Institutes of Health
TLC
The Treatment of Lead-exposed Children (TLC) clinical trial is designed to compare the effect of lead
chelation with succimer to placebo therapy on developmental status as measured by IQ scores three
years after initiation of treatment, in boys and girls initially between 12 and 33 months of
age with baseline blood lead concentrations (PbB) between 20 and 44 ug/dl. Residential lead clean-up and
nutritional supplementation with multivitamins and minerals are provided to all study
children, irrespective of treatment group.
