Further options for treating lipids in people with diabetes: targeting LDL-cholesterol and beyond

Abstract

Diabetes is associated with increased cardiovascular disease (CVD) risk. Previous studies with statins have established that a 1 mmol/l reduction in LDL-cholesterol reduces CVD events by 21% over 5 years in people with diabetes. More recently, trials in people with acute coronary syndromes showed that ezetimibe reduced CVD events by 6% at 5 years and achieved a LDL-cholesterol of 1.6 mmol/l with better results in people with Type 2 diabetes. Several novel lipid-lowering therapies have recently been developed. Most data have been accumulated with proprotein convertase subtilisin kexin-9 (PCSK-9) inhibitors, which reduce LDL-cholesterol by 50–55%. A large CVD outcome trial with evolocumab, in which 40% of participants had diabetes, achieved a LDL-cholesterol of 0.8 mmol/l and showed a consistent 20% relative risk reduction within 2 years, including in people with diabetes. Trials to increase HDL-cholesterol using cholesterol ester transfer protein (CETP) inhibitors have generally underwhelmed. Although anacetrapib reduced coronary ischaemic events by 7% in a population with chronic CVD, more expansive CVD endpoints were not improved. The complex nature of CETP inhibitor trial outcomes means that these compounds are not being developed further. Trials targeting inflammation-associated lipids have been generally unsuccessful but recent data on the interleukin-1B receptor antagonist canakinumab have shown a reduction in acute coronary intervention, validating this target although at the cost of increased infections. The ability to achieve low LDL-cholesterol with off-patent medications and the costs of novel therapies will confine the use of novel agents to subgroups of people at highest risk of CVD.