Effect of Age, Weight and Sex on Levothyroxine Pharmacokinetics

Hypothyroidism Primary Clinical Trial

Official title:

Hypothyroidism Treatment in Aging and Thyroid Cancer

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03102177
• Other study ID #: 2010-572
• Status: Completed
• Phase: Early Phase 1
• First received: March 27, 2017
• Last updated: April 4, 2017
• Start date: May 31, 2011
• Est. completion date: July 26, 2016

Study information

• Verified date: March 2017
• Source: Georgetown University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study was a prospective, single-center, open-label, non-randomized, pharmacokinetic study using stable isotope carbon-13 labeled levothyroxine

Description:

Setting The study was conducted on the clinical research unit of an academic medical center.

Participants Adults of any age being treated with levothyroxine for hypothyroidism were studied.

Interventions A single dose of 13C- LT4 was administered to hypothyroid subjects taking levothyroxine replacement.

Main Outcomes and Measures Eighteen serial plasma samples were collected. One sample was obtained before the 13C- LT4 dose and the remainder over the 312-hour period post-dosing. 13C- LT4 concentration was quantified using validated liquid chromatography tandem mass spectrometry methods. Pharmacokinetic analysis was conducted using linear log trapezoidal non-compartmental analysis using Phoenix 6.4.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 41
• Est. completion date: July 26, 2016
• Est. primary completion date: November 30, 2013
• Accepts healthy volunteers: No
• Gender: All
• Age group: 21 Years and older

Eligibility

Inclusion Criteria:

• age >21 years at the time of consent

• euthyroidism while undergoing treatment with LT4

• no other serious illness

• ability to give written informed consent.

Exclusion Criteria:

• baseline hematocrit lower than 28.0%

• TSH greater than 4.5 mIU/L

• kidney dysfunction

• concomitant use of drugs that affect thyroidal axis interactions

Related Conditions & MeSH terms

• Hypothyroidism
• Hypothyroidism Primary

Intervention

Drug:
• Administration of stable Isotope labeled levothyroxine
Administration of single dose of stable isotope carbon-13 labeled levothyroxine and measurement of blood levels of stable isotope-labeled levothyroxine

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
Georgetown University

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	CL/F	oral clearance rate (defined as the ratio of dose administered to AUC0-8)	120 hours
Primary	V/F	apparent volume of distribution (estimated by CL/F/ ?)	120 hours
Primary	t-half	the half-life of the terminal disposition phase (t-half) estimated by ln(2)/? .	120 hours
Secondary	CL/F analysed by age groups	CL/F will be compared in adults (age =60 years) versus elderly (age>60 years) using Wilcoxon signed-rank test using significance level of a = 0.05. Additionally, these PK parameters were regressed against age (as a continuous covariate).; Sex (male or female), weight (as a continuous covariate), and body mass index (BMI) (as a continuous covariate) will be considered using a stepwise linear regression approach.	120 hours
Secondary	V/F analysed by age groups	V/F will be compared in adults (age =60 years) versus elderly (age>60 years) using Wilcoxon signed-rank test using significance level of a = 0.05. Additionally, these PK parameters were regressed against age (as a continuous covariate).; Sex (male or female), weight (as a continuous covariate), and body mass index (BMI) (as a continuous covariate) will be considered using a stepwise linear regression approach.	120 hours
Secondary	t-half by age groups	t-half will be compared in adults (age =60 years) versus elderly (age>60 years) using Wilcoxon signed-rank test using significance level of a = 0.05. Additionally, these PK parameters were regressed against age (as a continuous covariate).; Sex (male or female), weight (as a continuous covariate), and body mass index (BMI) (as a continuous covariate) will be considered using a stepwise linear regression approach.	120 hours