Thyroid UK
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Proposed slow release T3 tablet trial in the US

I contacted Dr Jonkclaas who is supervising this trial to find out its scope. Regrettably it will only be very limited in numbers, so don't hold your breath as to the outcome and whether the small number of subjects is large enough to form a clear conclusion. Such small studies aren't well enough controlled to help us understand just how and where T3 could be beneficial, unless the outcome is so clear that analysis isn't necessary.

4 Replies

Thank you Diogenes. As you say, we won't hold our breath then :(

For anyone wondering what this is about, it's:

A Study of T3 Therapy in Patients With Hypothyroidism


The purpose of this study is to test a new thyroid hormone preparation. The thyroid gland produces two thyroid hormones: mostly T4 and a smaller amount of T3. Thyroid hormone therapy for hypothyroidism or thyroid cancer is generally provided using levothyroxine, which is a synthetic form of T4. T4 is converted into the active hormone T3 in the circulation. Therefore, some researchers believe that T3 levels in T4-treated patients may be slightly lower than in individuals whose own thyroid gland is functioning normally. Symptoms of hypothyroidism have been suggested to occur because of this possible T3 deficiency, although this is controversial. Studies of T3, added to or substituted for T4 in traditional levothyroxine regimens, have generally not shown any benefit of T3. However, it is still possible that no benefit is seen because of the short duration of action or "half-life" of T3. This short-life makes it necessary to dose T3 twice or three times daily. Despite multiple daily doses of T3, T3 levels during its therapy tend to be troubled by peaks and troughs. These peaks can be associated with symptoms of excessive thyroid hormone levels. This study will look at TSH and thyroid hormone levels following a daily dose of a new preparation of T3 that may have longer duration of action than liothyronine. This preparation of T3 is called Thyromax® or BCT303. The investigators believe that steady levels of T3 will be seen after taking Thyromax®. The investigators believe that in patients with hypothyroidism use of Thyromax® in the correct dose will produce normal TSH levels, without producing symptoms of too much thyroid hormone. The goal of future studies is to test whether Thyromax® may be a potential treatment for hypothyroidism, by comparing it with traditional levothyroxine therapy.


My concern with this trail is that they are taking patients on T4 and giving them the new drug but for me and others the first 8 weeks of the changeover to straight T3 were horrendous (possibly until T4 had left the body). So I would be concerned that some patients would feel worse at first and this may cause problems with their data. Would you be able to clarify this point with the research? I can't recall how long the trial will be. Many thanks, Mary.


Sample size is very small. Seems like they are all going to be recruited from small population. Study period 6 weeks? Are participants going to be given any time to clear system of thyroxine? If not then patients may do better in interim and feel worse after a few weeks whilst systems balance out. Conversely, they may feel very hypo as it takes a time for thyroxine to leave the system. Trial period does not seem long enough. Primary method of showing effects are Serum total T3 and TSH. There are no qualitative measures being used such as questionnaires capturing mood change, cognitive function tests, lessening of pain , etc If I were conducting a study of such small magnitude I would be anxious to capture participant opinion rather than crude blood samples.

Sorry this trial seems worthless but let us hope something positive comes out of it.

Can anyone explain who Ipe, LLC are so that I can follow this trial through to outcome?




Ipe could be Interprofessional Education. Both of these acronyms seem to be concerned with government-led organizations. See Wikipedia for Ipe definitions.


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