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Generic vs. Name-Brand Levothyroxine

This study has been completed.
Information provided by:
Boston Children’s Hospital Identifier:
First received: November 21, 2006
Last updated: December 2, 2010
Last verified: December 2010
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 Intervention Phase
Congenital Hypothyroidism Hypothyroidism Drug: Levothyroxine versus Levothyroxine Phase 3

Study Type: Interventional
Study Design: 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

Resource links provided by NLM:

Further study details as provided by Boston Children’s Hospital:

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

Enrollment: 34
Study Start Date: November 2006
Study Completion Date: March 2010
Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)
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)
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.

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: 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
  More Information

Responsible Party: Rosalind Brown, MD Clinical Trials Director, Children's Hospital Boston Identifier: NCT00403390     History of Changes
Other Study ID Numbers: 05-11-146
Study First Received: November 21, 2006
Last Updated: December 2, 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 processed this record on September 21, 2017