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Taking people in United StatesPhase 4

Flexible levothyroxine dosing for older people with underactive thyroid

Tests more flexible levothyroxine dosing in older adults with hypothyroidism.

Key facts

Who runs it
University of Pennsylvania
Where
Philadelphia, United StatesSee the site
Trial code
Registry title
Dosing of LT4 in Older Individuals
Status
Recruiting
Phase
Phase 4
People taking part
228 people, planned
Started
31 Jan 2024
Expected to end
1 Apr 2028
Type of study
Interventional, 2 groupsOne group gets an existing treatment, for comparison.
Treatments tested
  • Levothyroxine Sodium
Record updated
19 February 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for people aged 65 years or older who live in the community and take LT4 (levothyroxine) for an underactive thyroid. It compares two target TSH levels.

Age
65 years or older
Sex
Men and women
Disease stage
Hypothyroidism (underactive thyroid) of any cause, diagnosed for at least 6 months.
Earlier treatment
Must be taking 75-200 mcg per day of LT4, and at least 1.2 mcg/kg/day. The dose must not have changed since the last TSH test.

Main reasons for not taking part

  • Hypopituitarism (underactive pituitary gland)
  • History of thyroid cancer needing TSH to be kept low
  • Current use of liothyronine (LT3), thyroid extracts, Tirosint, or drugs that affect thyroid function or thyroid tests
  • GFR <30 ml/min/1.73 m2 (poor kidney function) within the prior 12 months
  • Currently taking multikinase or checkpoint inhibitor therapy, or any history of food dye allergy

The registry criteria, word for word

Show all 14 criteriaShow less

Who can take part

  • Provision of signed and dated informed consent form
  • Stated willingness to comply with all study procedures and availability for the duration of the study
  • Male or female, community dwelling, aged 65 years or older
  • Diagnosed with hypothyroidism of any etiology for at least 6 months, taking 75-200 mcg per day LT4 and a minimum of 1.2 mcg/kg/day with no dose adjustment since the last TSH test
  • Ability to take oral medication and be willing to adhere to the medication regimen
  • Adherence to lifestyle considerations

Who cannot take part

  • Current use of liothyronine (LT3), thyroid extracts, Tirosint liquid or capsules, and medications that interfere with thyroid function or thyroid function tests
  • Currently taking multikinase or checkpoint inhibitor therapy
  • History of thyroid cancer requiring suppression of TSH secretion
  • Other conditions which, in the opinion of the investigators, would prevent them from participating in the full duration of the study
  • Any history of food dye allergy
  • GFR <30 ml/min/1.73 m2 within the prior 12 months
  • Hypopituitarism
  • Unable to understand and comply with study requirements, as assessed by study staff and the PI, will be excluded

Where in United States

  • Penn Medicine, Smilow Translational Research CenterPhiladelphia, United StatesContact: Anne R. Cappola, M.D., Sc.M.Taking people

About the trial

What the trial wants to find out

Our overall goal is to determine the clinical consequences of allowing greater flexibility in LT4 dosing in older individuals who take LT4.

The 2 groups in the trial

  • Lower TSH GroupExisting treatment, for comparison

    Target TSH level of 0.5-2.0 mU/L

    Treatment: Levothyroxine Sodium

  • Higher TSH groupTreatment being tested

    Target TSH level of 5.5-7.0 mU/L

    Treatment: Levothyroxine Sodium

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov.
Official title
Levothyroxine Dosing in Older Individuals
Plain-language title
Flexible levothyroxine dosing for older people with underactive thyroidGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 14 November 2026.
Record updated
19 February 2026