Dr. Michael Fulks highlights an emerging LDL-lowering therapy that may also reduce Lp(a), offering new context for interpreting cardiovascular risk assessment.
Lp(a) is now identified as an important lipid particle promoting atherosclerosis just as LDL (apoB) does. Because of this, an Lp(a) test is part of the new CRL Advanced Cardiovascular Risk Panel along with apoB and hs-CRP. One reason Lp(a) is less discussed than LDL is that there is no currently available therapy specifically targeting it which limits clinical interest. Because Lp(a) has a different metabolic pathway than other lipids including LDL, statins and diet do not reduce Lp(a) levels. Highly effective Lp(a) treatment is on the way but 1 to 2 years away.
Not being aware of any current treatment for elevated Lp(a), I was surprised by a recent NEJM article on a new orally-available PCSK9 inhibitor, Enlicitide (these drugs are prescribed to reduce LDL levels further when statins are not sufficient) which noted that Lp(a) levels were also reduced by 26% during the one-year trial. Further literature review revealed that this is similar to the reduction seen with the currently available, injectable-only, PCSK9 inhibitors such as alirocumab and evolocumab. This class of drugs is fairly new, expensive, and is used for LDL reduction in only a small minority of patients although it is highly efficacious. Having an orally available PCSK9 inhibitor such as Enlicitide plus the increasing recognition that LDL (apoB) reduction to very low levels is vital to reducing the risk of future cardiovascular events may improve this underutilization. The accompanying reduction of Lp(a) levels by over 25% should be enough to add risk reduction especially for patients where the Lp(a) level is elevated.
So, we do actually have a class of drugs that can currently be used to reduce Lp(a) although these PCSK9 inhibitors are likely to be prescribed (and covered by insurance) only if also needed to further reduce LDL while on maximal statin Rx or if statins are not tolerated. The increasing use of PCSK9 drugs and soon to be available drugs targeting Lp(a) directly make checking the Lp(a) level as part of a clinical or life insurance lipid profile even more valuable.
About the Author
Michael Fulks, MD, Consulting Medical Director, is board-certified in internal and insurance medicine. After leaving practice, he served as a medical director, creating or editing several underwriting manuals and preferred programs. More recently, Mike has consulted for CRL participating in its mortality research on laboratory test results, BP and build, and in the development of risk-scoring tools for laboratory and non-laboratory data.