Eprotirome (KB2115) is a liver selective thyroid hormone that can induce hyperthyroidism in the liver, while an euthyroid state is preserved in the extrahepatic tissue. Eprotirome has in clinical trials demonstrated pronounced reduction of several independent risk factors for the development of atherosclerotic cardiovascular diseases.

The purpose of the study is to assess the efficacy and safety of KB2115 as add on therapy to ezetimibe following 10 weeks of exposure compared to placebo. The aim of the study is to assess efficacy (LDL-cholesterol lowering effects) and safety of KB2115 and to define a clinically relevant dose or dose range for future studies.

Inclusion Criteria:

• Males or females aged 18 to 75 years
• Patient with primary hypercholesterolemia with an LDL-cholesterol > 3.0 mmol/L
• At randomization, diet as instructed by the investigator during the last 4 weeks prior to randomization and willingness to follow these instructions throughout the study

Exclusion Criteria:

• History of somatic or psychiatric disease/condition, which may interfere with the objectives of the study