Eprotirome in patients with familial hypercholesterolaemia (the AKKA trial): a randomised, double-blind, placebo-controlled phase 3 study
Abstract
Eprotirome is a liver-selective thyroid hormone receptor agonist that has been shown to lower plasma LDL cholesterol concentrations in previous phase 1 and 2 studies of patients with dyslipidaemia. We used a computer-generated randomisation sequence to allocate patients to one of three groups: 50 mu g eprotirome, 100 mu g eprotirome, or placebo.
T Analysis was done in all patients who received 6 weeks of treatment. This study is registered with ClinicalTrials.gov, number NCT01410383.
We enrolled 236 patients, randomly allocating 80 to receive placebo, 79 to receive 50 mu g eprotirome, and 77 to receive 100 mu g eprotirome. 69 patients reached the 6 week timepoint (23 given placebo, 24 given 50 mu g eprotirome, and 22 given 100 mu g eprotirome). Mean LDL cholesterol concentrations increased by 9% (95% CI -2 to 20) in the placebo group, decreased by 12% (-28 to 4%; p=0.0677 vs placebo) in the 50 mu g eprotirome group, and decreased by 22% (-32 to -13%; p=0.0045 vs placebo) in the 100 mu g eprotirome group.
Four patients had to discontinue or interrupt study treatment before trial termination due to AST increases between the upper limit of normal (ULN) and six times ULN, and ALT concentrations between three and seven times ULN. Although we detected no changes in serum concentrations of thyroid-stimulating hormone or free tri-iodothyronine, free tetra-iodothyronine decreased by 19% (23 to 16) in the 50 mu g eprotirome group and 27% (30 to 23) in the 100 mu g eprotirome group (p<0.0001 vs placebo for both groups).
Interpretation Our findings show that eprotirome can lower LDL cholesterol concentrations in patients with familial hypercholesterolaemia when added to conventional statin treatment with or without ezetimibe, but that it has the potential to induce liver injury. These findings, along with findings of cartilage damage in dogs, raise serious doubts about selective thyroid hormone mimetics as a therapeutic approach to lower LDL cholesterol concentrations.