T3-HF

A randomised, double-blind, placebo-controlled trial to evaluate the efficacy of orally administered Triiodothyronine (T3) for 24 weeks in patients with heart failure with reduced ejection (HFrEF).

Background

Heart failure (HF) is the name given to the condition where the heart is not pumping blood well enough to maintain normal health. Symptoms include breathlessness, tiredness, light-headedness and swollen ankles. While symptoms may be managed for many years, there is no cure for heart failure and symptoms usually get worse over time. Nearly 1 million people in the UK have heart failure and the NHS spend approximately £2 billion on heart failure treatments every year. Heart failure with reduced ejection fraction (HFrEF) is the most common form of heart failure and is associated with increased hospital admissions and reduced exercise tolerance, impaired quality of life and increased mortality.

Thyroid hormones control metabolic processes in the heart and are needed for the heart to function normally. Between 10 to 25% of people with HFrEF have low levels of the active thyroid hormone, triiodothyronine (T3), in the bloodstream and heart muscle. The risk of mortality is more than double in people with HFrEF and low T3 than people with HFrEf and normal T3 levels. Therefore, people with HFrEF and low T3 levels are an especially high-risk group of patients. A meta-analysis of three small randomised controlled trials where participants with HFrEF took T3 supplementation demonstrated that treatment with T3 is safe and may improve heart function. An appropriately powered trial is needed to evaluate the efficacy and safety of T3 supplementation in a larger group of participants.

Trial design

This trial will test the effect of taking synthetic T3 hormone tablets twice daily for 24-weeks on exercise tolerance in people with HFrEF and low T3 compared with a placebo (“dummy” pill). It will be a ‘randomised’ trial. This means that participants will be randomly allocated to take either the T3 or placebo tablets . Everything else will be the same. The distance walked during a 6-minute walk test will then be compared between those who took the T3 and those who took the placebo. 258 participants from ~14 NHS hospitals will be randomised.  Participants will be followed up 12 weeks and 24 weeks after starting the trial treatment.

Patient and public involvement

Two members of the public are a part of our trial management group and another member of the public is part of our trial steering committee. We also have a patient advisory group who will work with us throughout the trial.