Cutting cholesterol levels dramatically
- Wits University
World Health Day: Hope for effectively treating patients with Familial Hypercholesterolaemia (FH).
The death of a 10-year-old boy in the 1990s inspired Professor Derick Raal to dedicate his life to finding a treatment for homozygous Familial Hypercholesterolaemia.
At the time, there was little treatment for the genetic condition that is caused by a defect on chromosome 19, which renders the body unable to remove Low-Density Lipoprotein (LDL) cholesterol from the blood.
The condition causes extremely high levels of LDL cholesterol to build up in a person’s body, clogging the arteries and causing cardiac disease and heart attacks at extremely young ages.
Raal’s dedication to his research, however, resulted in the highly satisfying result of medication that could be used to effectively treat patients with Familial Hypercholesterolaemia (FH).
“It has been a remarkable journey since the 1990s from virtually unable to treat the condition to finding a cure. It does mean that you are on medication for life but you are able to live a normal, healthy life,” explains Raal.
The medication developed from his research was approved by the US Food and Drug Administration in July 2015.
Raal, the Director of the Carbohydrate and Lipid Metabolism Research Unit at Wits specialises in both heterozygous and homozygous FH. Heterozygous FH, the “single dose” is one of the most commonly inherited conditions and affects one in every 250 people worldwide.
In South Africa, the Afrikaner, Indian and Jewish communities are especially affected, with one in every 80 people living with the condition. Homozygous FH, the “double dose” is rare, but is even more serious and is caused when a child inherits the defective genes from both his parents.
Unable to process LDL cholesterol at all, the result is that four times the normal amount of cholesterol builds up in the body.
“Patients with this condition often die of heart attacks as teenagers,” says Raal. “It is devastating to see young people dying from this condition. That is what got me into this field of research.”
Unlike dietary induced high cholesterol, which is caused by a bad lifestyle and can be reduced by a healthy diet and regular exercise, FH in both forms needs to be treated with medication for life.
Raal’s research into finding a treatment for the condition led to the development of a drug called Mipomersen.
The drug cuts cholesterol levels of people living with FH by 30%. His research was published in The Lancet in 2010 and this article has been cited almost 400 times.
“It was quite a breakthrough, but not enough,” says Raal.
He continued his work, which led to the development of PCSK9 inhibitors that can cut cholesterol levels by a further 60%.
His two papers on the use of this medication in heterozygous and homozygous FH were also published in The Lancet in January 2015. “We have basically cured heterozygous FH,” says Raal.
The PCSK9 inhibitors bring cholesterol levels of patients living with heterozygous FH down to normal levels, whilst it brings the cholesterol levels of patients living with homozygous FH down to the levels of those with heterozygous FH. The problem with FH, however, is that it is difficult to diagnose, as sufferers are not aware that they are living with the condition.
“Until one suffers a heart attack or stroke, FH is asymptomatic, so people do not feel sick and do not realise they have the condition,” adds Raal. “With an estimated 200 000 people in South Africa living with FH, the challenge now is to identify these subjects.”
Raal has received numerous awards for his work. He has co-authored over 170 articles and has reviewed for several international journals, including The New England Journal of Medicine, The Lancet, The American Journal of Cardiology, Diabetes Care, Atherosclerosis and Arteriosclerosis, Thrombosis and Vascular Biology.
He is also a member of several scientific societies.