By CardioSmart News
There is good news for people living with
familial hypercholesterolemia (FH), a genetic condition that causes high levels of “bad” cholesterol beginning at birth and can lead to
heart attacks often early in their lives.
Research published in the
Journal of the American College of Cardiology finds that evolocumab, a new type of treatment for lowering cholesterol called a PCSK-9 inhibitor, notably cut low-density lipoprotein (LDL) or the “bad” cholesterol in people with two types of FH, homozygous FH and heterozygous FH. The drug also allowed 1 in 4 patients who needed it to discontinue lipoprotein apheresis, a procedure that removes LDL cholesterol from the blood.
The goal of this study was to make sure that taking evolocumab for five years was both safe and effective. The study ended about a year early because of the clearly positive results. Researchers wrote that this is the longest follow up of any study of a PCSK9 inhibitor among people with FH and that, based on the data, “evolocumab was well tolerated and effectively reduced LDL-C, with the results sustained over a median of 4.1 years.” The study was funded by Amgen, the manufacturer of evolocumab.
Evolocumab works by blocking a certain protein called PCSK9 that, in turn, helps the liver remove and clear LDL-C from the blood. To date, it is the only PCSK9 inhibitor therapy approved for use in addition to adopting a heart-healthy diet and being on maximally tolerated statin therapy in both homozygous FH and heterozygous FH.
The study, called TAUSSIG, enrolled 300 patients with FH who were at least 12 years of age. Of these, 194 had heterozygous FH and the remaining 106 had homozygous FH. To be in the trial, patients had to be on a statin for at least four weeks before the start of the study. Statins are typically the first medicine someone will take for cholesterol-lowering, but for most people with FH, statins don’t drive down their cholesterol levels enough even with the addition of ezetimibe, another cholesterol-lowering medicine. Patients also had to have one of these: 1) LDL ≥ 130 mg/dL or 2) LDL ≥ 100 mg/dL with a diagnosis of coronary heart disease or other heart issues or 3) be undergoing apheresis treatment every two weeks.
Those undergoing lipoprotein apheresis started on a 420 mg dose of evolocumab given by injection once every two weeks. The other patients also received 420 mg, but the injection was given once a month. After 12 weeks, a clinician could decide whether to move these patients to 420 mg every 2 weeks. The higher dose of evolocumab used in this trial is not currently approved in the U.S.
Overall, the drug was well tolerated. The most common side effects reported were the common cold, influenza, other upper respiratory tract infections, headache, muscle pain, and diarrhea. Researchers found that evolocumab given every two weeks or once a month reduced “bad” cholesterol by 21% among people with homozygous HF, representing an average drop in LDL of 60 mg/dL and by 54% in those with heterozygous FH, which meant an average 104 mg/dL drop.
Experts say such drops in LDL should also translate into a lower risk of related heart attacks, strokes or even early deaths among these patients. The fact that there is variation in how certain patients respond to evolocumab, especially between the two types of FH, was noted by researchers and should be further studied. People with homozygous FH still required additional agents to lower blood pressure.
Limitations of the study included that both the researchers and participants knew the treatment being received. Also, the study ended early because enough evidence had been gathered to answer the main study questions. Still, the study is overall a win in caring for people with FH.
About 1 in 250 adults have FH, an inherited condition that affects the heart and blood vessels. For many, a heart attack in their 30s or 40s is what sounds the alarm and when they first learn they have the condition.
Read the full article: “Long-Term Evolocumab in Patients With Familial Hypercholesterolemia,” Journal of the American College of Cardiology, Feb. 6, 2020.