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Generic vs. Name-Brand Levothyroxine

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ClinicalTrials.gov Identifier: NCT00403390
Recruitment Status : Completed
First Posted : November 23, 2006
Last Update Posted : December 3, 2010
Information provided by:
Boston Children’s Hospital

Brief Summary:
This study compares two different brands of thyroxine (thyroid hormone). Currently, pharmacists may be substituting generic formulations of thyroid hormone without your doctor knowing about this. Although a small difference in thyroid function is not significant in most healthy children, adolescents and adults, in infants and toddlers even a small difference in thyroid function can have important harmful consequences on brain development. The purpose of the present study is to learn whether the difference between brands of thyroid hormone that are currently being substituted is sufficient to cause a difference in thyroid function.

Condition or disease Intervention/treatment Phase
Congenital Hypothyroidism Hypothyroidism Drug: Levothyroxine versus Levothyroxine Phase 3

Detailed Description:
This study is an unblinded, randomized controlled cross-over study, which involves taking 2 different forms of levothyroxine sequentially over a 16 week period. Subjects will have a total of 3 visits over this time period. At the first visit, subjects are randomized to receive either generic (Sandoz) levothyroxine or Synthroid (Abbott) brand of levothyroxine. Blood is drawn for baseline thyroid function studies and other markers which are influenced by thyroid hormone at each visit. The second visit is the cross-over visit, and the final visit is a close-out visit, after which each subject will resume taking their previous formulation of levothyroxine.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 34 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: Generic vs. Name-Brand Levothyroxine: Assessment of Bioequivalence Using TSH as a Marker in Children With Permanent Hypothyroidism
Study Start Date : November 2006
Primary Completion Date : December 2009
Study Completion Date : March 2010

Intervention Details:
    Drug: Levothyroxine versus Levothyroxine
    Randomized crossover study using 8 weeks of one form of levothyroxine, then 8 weeks of the other form of levothyroxine. The dose of medication does not change throughout the duration of the study.
    Other Names:
    • Levothyroxine (manufactured by Sandoz)
    • Synthroid (manufactured by Abbott)

Primary Outcome Measures :
  1. Thyroid Stimulating Hormone Measure [ Time Frame: 3 points over 16 weeks ]

Information from the National Library of Medicine

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Ages Eligible for Study:   3 Years to 18 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Age between 3 and 18 years
  • Diagnosis of Congenital Hypothyroidism with initial TSH > 100
  • Ability to understand directions and follow all instructions

Exclusion Criteria:

  • Not on any drug interfering with absorption of levothyroxine

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00403390

United States, Massachusetts
Children's Hospital Boston
Boston, Massachusetts, United States, 02115
Sponsors and Collaborators
Boston Children’s Hospital
Principal Investigator: Rosalind S Brown, MD Boston Children’s Hospital

Responsible Party: Rosalind Brown, MD Clinical Trials Director, Children's Hospital Boston
ClinicalTrials.gov Identifier: NCT00403390     History of Changes
Other Study ID Numbers: 05-11-146
First Posted: November 23, 2006    Key Record Dates
Last Update Posted: December 3, 2010
Last Verified: December 2010

Additional relevant MeSH terms:
Congenital Hypothyroidism
Thyroid Diseases
Endocrine System Diseases
Bone Diseases, Developmental
Bone Diseases
Musculoskeletal Diseases
Bone Diseases, Endocrine
Genetic Diseases, Inborn