PCSK9 Inhibitors: How Low Can You Go?

By now, we’re all familiar with statins, a group of medicines that can help lower the level of low-density lipoprotein (LDL) cholesterol in the blood. We often refer to LDL cholesterol as the ‘bad cholesterol’ as it can lead to a hardening and narrowing of the arteries and cardiovascular disease (CVD) – the most common cause of death in the UK. The main types of CVD are heart attack, stroke, coronary heart disease and stroke. Statins are now the most commonly prescribed medicines in the UK and although there are different types they all work in the same way.

If you have a high risk of heart disease the chances are that you are already taking a statin, as well as doing everything you can to stay healthy such as regular exercise, maintaining a healthy weight and tracking your blood pressure. Now a new class of agents called PCSK9 inhibitors are being developed to lower cholesterol. These drugs all act on the PCSK9 protein which is produced by liver cells and is responsible for breaking down cholesterol receptors which sit on the surface of healthy liver cells.


The medications, called PCSK9 inhibitors, are administered by injection and can reduce LDL levels by a whopping 60 mg/dl on average, in some cases, bringing LDL cholesterol down to less than 25mg/dL, around the level of a newborn baby! Following the initial trials, some experts believed that we might be able to virtually eliminate heart disease altogether. However, drugs can be unpredictable with many effects. A drug that lowers one risk, may still have other effects that could potentially offset the benefit. Therefore more studies have followed and continue. Over the past two years of study, researchers found that the new drug, when added to a statin, reduced the risk of heart attack or stroke by 15%. For about every 70 people treated with the drug, one person benefited in this way. This is not far off the size of the benefit that statins provide. The studies also concluded that no safety concerns emerged, however, expectations prior to the studies had been much higher – that such low LDL cholesterol levels would almost eliminate the heart attacks caused by high levels.

In conclusion, the benefit of PCSK9 inhibitors is greatest among those with the most risk, those who despite treatment and statins, still have very high LDL cholesterol levels. In this case, you may be the one in 70 that benefits. However, another downside to PCSK9 inhibitors is the cost, with each prescription costing c.£4,000 per person, per year, but these prices should eventually come down. There could also be new conclusions in studies to show that the benefit of taking these drugs increases over time. Watch this space.