Levothyroxine Replacement With Liquid Gel Capsules vs Tablets Post-thyroidectomy

Study ID
STU 022015-044

Study Sites

  • CTRC Outpatient

Contact
Bianca Mobley
214/648-6209
Bianca.Mobley@UTSouthwestern.edu

Principal Investigator
Alex Tessnow, M.D.

Official Title

Levothyroxine Replacement With Liquid Gel Capsules or Tablets in Post-thyroidectomy Stage in Low Risk Differentiated Thyroid Cancer Patients

Brief Overview

In some patients, levothyroxine liquid gel capsules may demonstrate superior absorption than the tablet option. Impaired absorption of thyroid hormone directly correlates to higher and more unpredictable TSH (thyroid stimulating hormone) levels.
The investigators therefore hypothesize that following thyroidectomy for Stage I/II differentiated thyroid cancer the gel capsule levothyroxine formulation will provide more predictable TSH results and in turn require fewer dose adjustments to achieve optimal hormone levels in the postoperative period.
The aim of this investigation is to compare the use of levothyroxine in liquid gel capsules to tablet form for TSH suppression following thyroidectomy for presumed stage I/II differentiated thyroid cancer.

Description

Ten patients will be randomized prior to surgery to receive levothyroxine in tablet form and ten patients will be randomized to receive in gel capsule form. Both forms will be encapsulated in order to allow double-blinding of the study.
The postoperative goal TSH will be between 0.1 and 0.5 mU/L in both arms. Patients will be seen at weeks 6, 12 and 18 postoperatively and have TSH and Free T4 measured. The primary outcome is the number of patients at each visit that are at goal range TSH.
A secondary analysis will compare the dose changes required between the two groups in order to achieve goal TSH.
Another secondary analysis will investigate the patients' quality of life. Two different surveys (see secondary outcomes below) will be performed at both study entry and completion to compare the two groups.

Eligibility

Inclusion Criteria:
- Age > 18 years
- Presumed AJCC (American Joint Committee on Cancer) tumor Stage I or II
- Planned total or near-total thyroidectomy
- Planned goal TSH suppression 0.1-0.5 mU/L for at least 18 weeks postoperatively
- Normal serum TSH within 12 months preceding surgery
Exclusion Criteria:
- AJCC Stage III or greater
- Undifferentiated, Anaplastic or Medullary Thyroid Cancer
- Planned postoperative TSH goal other than 0.1-0.5 mU/L
- History of gastrointestinal malabsorption or gastric bypass surgery
- Pregnancy
- Use of medications that alter the absorption or metabolism of levothyroxine
- Prior use of levothyroxine