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Clinical Trial Details — Status: Completed

Administrative data

NCT number NCT00001721
Other study ID # 980081
Secondary ID 98-CH-0081
Status Completed
Phase
First received
Last updated
Start date September 13, 1998

Study information

Verified date January 22, 2024
Source National Institutes of Health Clinical Center (CC)
Contact n/a
Is FDA regulated No
Health authority
Study type Observational

Clinical Trial Summary

Smith-Lemli-Opitz Syndrome (SLOS) is a genetic disorder (autosomal recessive) caused by an abnormality in the production of cholesterol. The disorder can occur in both a "mild" or "severe" form. SLOS is associated with multiple birth defects and mental retardation. Some of the birth defects include; abnormal facial features, poor muscle tone, poor growth, shortened life span, and abnormalities of the heart, lungs, brain, gastrointestinal tract, limbs, genitalia, and kidneys. There is no known cure for SLOS but recently patients have been treated with increased amounts of cholesterol in their diet. The cholesterol in a persons diet is unable to correct the abnormalities in the patient's organs, but researchers hope it will improve growth failure and mental retardation. This study was developed to answer questions about the causes and complications of SLOS, as well as the effectiveness of cholesterol treatment. The study will enroll patients diagnosed with SLOS, and their mothers. The objectives of the study will be to address the following questions: 1. <TAB> What is the prognosis / natural history of the demyelination in the nervous system of patients with SLOS? 2. <TAB> Do patients with SLOS have other problems concerning the function of their endocrine systems? 3. <TAB>What are the genetic make-ups of patients with SLOS? 4. <TAB>Can further studies of cholesterol metabolism and genetic testing, using SLOS fibroblasts, increase the understanding of SLOS?<TAB>...


Description:

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive multiple congenital anomaly/mental retardation syndrome. Typical clinical features include a distinctive facial appearance, mental retardation, autistic behavior, hypotonia, failure to feed, poor growth, decreased life span, and variable structural anomalies of the heart, lungs, brain, gastrointestinal tract, limbs, genitalia and kidneys. The SLOS phenotypic spectrum is broad and variable. At the severe end of the spectrum SLOS is a lethal disorder with multiple major congenital anomalies; whereas, mild cases of SLOS present with a combination of minor physical stigmata, behavioral problems, and learning disabilities. SLOS is due to an inborn error of cholesterol biosynthesis. Biochemically, SLOS patients have a deficiency of 3beta-hydroxysterol delta(7)-reductase activity. 3beta-hydroxysterol delta(7)-reductase is an NADPH dependent microsomal enzyme that catalyzes the reduction of the C7(8) double bond of 7-dehydrocholesterol (7-DHC) to yield cholesterol in the last step of cholesterol biosynthesis via the Kandutsch-Russel pathway. This inborn error of cholesterol biosynthesis results in elevated tissue and serum 7-DHC levels and typically decreased serum and tissue cholesterol levels. In 1998 we established that the deficiency in 3beta-hydroxysterol delta(7)-reductase activity is due to mutation of the 3beta-hydroxysterol delta(7)-reductase gene (DHCR7). Once the biochemical defect in SLOS was identified, dietary cholesterol supplementation was proposed and employed as a therapeutic approach. Although developmental malformations remain fixed, dietary cholesterol supplementation appears to improve the overall health of these patients, and initial results have shown that dietary cholesterol supplementation has had a positive impact on some of the behavioral manifestations of this disorder. Although our understanding of this disorder has advanced over the last few years, many questions remain concerning the effectiveness of cholesterol replacement therapy, the long term prognosis for individuals on dietary cholesterol supplementation, and the need for adjunctive measures in the clinical management of SLOS patients. We propose to answer some of these questions by continuing our longitudinal natural history/prognosis study on patients with SLOS. We also plan on studying very closely related disorders such as lathosterolosis under this protocol. Lathosterolosis is caused by a deficiency in the enzyme sterol 3-beta-hydroxysteroid-delta-5-desaturase which is necessary for the conversion of lathosterol into 7-DHC. The clinical picture is very similar to SLOS with prominent features including microcephaly, ptosis bilateral 2,3 toe syndactyly. Lathosterolosis is also inherited in an autosomal recessive manner. Lethosterolosis is extremely rare with only 4 cases described in the literature so far and an estimated incidence of less than 1 in a million. The below objectives, protocol evaluations, risks, benefits and other pertinent issues apply to SLOS and lathosterolosis even if lathosterolosis is not explicitly named.


Recruitment information / eligibility

Status Completed
Enrollment 130
Est. completion date
Est. primary completion date
Accepts healthy volunteers No
Gender All
Age group N/A and older
Eligibility - INCLUSION CRITERIA: - Any patient with biochemically confirmed SLOS will be accepted into this study. Patients of any age, either gender, or any ethnicity will be accepted into this study. No exclusions will be made based on race or gender. Historically, more males than females have been diagnosed as having SLOS. This bias was likely a result of the fact that genital hypoplasia is readily apparent in a male, and therefore the clinical diagnosis is easier to make in a male patient. SLOS syndrome appears more commonly in individuals of Northern European ancestry. Out of 150 biochemically proven cases, only one was an African American and no patients of Asian descent were reported. One SLOS mutant allele (R404C) appears to be present in individuals of French Canadian and Creole heritage. This likely represents a founder effect. One puzzling finding is that the carrier rate of the most common SLOS mutant allele in Black Canadians from Ontario and African Americans from Pennsylvania appears to be approximately 0.7%. However, clinical cases appear to be rare. The predominance of Caucasians reported in the literature may represent a bias of ascertainment of the disorder, variable presentation in different ethnic groups, or a founder effect in some ethnic groups. Because we function as a referral center with respect to recruitment, the ethnic background of our population is likely going to reflect the overall population of diagnosed cases. EXCLUSION CRITERIA: - Patients will be excluded if they cannot travel to the NIH because of their medical condition. - Pregnant women will be excluded, and a negative urine pregnancy test will be required of menstruating women. This protocol focuses on biosampling. Increasing blood draws during pregnancy for research is not appropriate. Fetuses will be excluded since the proposed evaluations are not possible during fetal life.

Study Design


Intervention

Drug:
Cholesterol Suspension

CRH

Cholesterol


Locations

Country Name City State
United States National Institutes of Health Clinical Center Bethesda Maryland

Sponsors (1)

Lead Sponsor Collaborator
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Country where clinical trial is conducted

United States, 

References & Publications (3)

Elias ER, Irons MB, Hurley AD, Tint GS, Salen G. Clinical effects of cholesterol supplementation in six patients with the Smith-Lemli-Opitz syndrome (SLOS). Am J Med Genet. 1997 Jan 31;68(3):305-10. doi: 10.1002/(sici)1096-8628(19970131)68:33.0.co;2-x. — View Citation

Irons M, Elias ER, Abuelo D, Bull MJ, Greene CL, Johnson VP, Keppen L, Schanen C, Tint GS, Salen G. Treatment of Smith-Lemli-Opitz syndrome: results of a multicenter trial. Am J Med Genet. 1997 Jan 31;68(3):311-4. — View Citation

Opitz JM. RSH/SLO ("Smith-Lemli-Opitz") syndrome: historical, genetic, and developmental considerations. Am J Med Genet. 1994 May 1;50(4):344-6. doi: 10.1002/ajmg.1320500408. — View Citation

Outcome

Type Measure Description Time frame Safety issue
Primary Neurocognitive Evalustion Stabilization Yearly
See also
  Status Clinical Trial Phase
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Recruiting NCT05687474 - Baby Detect : Genomic Newborn Screening
Enrolling by invitation NCT03655223 - Early Check: Expanded Screening in Newborns
Recruiting NCT00004347 - Phase II Study of Dietary Cholesterol for Smith-Lemli-Opitz Syndrome Phase 2
Completed NCT03720990 - Smith-Lemli-Opitz Syndrome and Cholic Acid Phase 1/Phase 2
Completed NCT00114634 - Short-term Behavioral Effects of Cholesterol Therapy in Smith-Lemli-Opitz Syndrome Phase 2
Completed NCT00017732 - Estimation of the Carrier Frequency and Incidence of Smith-Lemli-Opitz Syndrome in African Americans N/A
Completed NCT00064792 - Simvastatin Therapy in Smith-Lemli-Opitz Syndrome Phase 2
Recruiting NCT05642221 - Functional Near-Infrared Spectroscopy (fNIRS) Combined With Diffuse Correlation Spectroscopy (DCS) in Neurocognitive Disease as Compared to Healthy Neurotypical Controls
Terminated NCT01356420 - Sterol and Isoprenoid Disease Research Consortium: Smith-Lemli-Opitz Syndrome N/A
Completed NCT00272844 - Treatment of the Cholesterol Defect in Smith-Lemli-Opitz Syndrome Phase 1/Phase 2
Recruiting NCT01773278 - Cholesterol and Antioxidant Treatment in Patients With Smith-Lemli-Opitz Syndrome (SLOS) Phase 2
Completed NCT00070850 - Prenatal Screening For Smith-Lemli-Opitz Syndrome Phase 2