Novel Approaches for the Treatment of Familial Hypercholesterolemia: Current Status and Future Challenges

Familial hypercholesterolemia (FH) is an autosomal-dominant disorder that is characterized by high plasma lowdensity lipoprotein cholesterol (LDL-c) levels and an increased risk of cardiovascular disease. Despite the use of high-dose statins and the recent addition of proprotein convertase subtilisin/kexin type 9 inhibitors as a treatment option, many patients with homozygous FH fail to achieve optimal reductions of LDL-c levels. Gene therapy has become one of the most promising research directions for contemporary life sciences and is a potential treatment option for FH. Recent studies have confirmed the efficacy of a recombinant adeno-associated virus 8 vector expressing the human LDL-c receptor gene in a mouse model, and this vector is currently in phase 2 clinical trials. Much progress has also been achieved in the fields of antisense oligonucleotide- and small interfering RNA-based gene therapies, which are in phase 1–2 clinical trials. In addition, novel approaches, such as the use of minicircle DNA vectors, microRNAs, long non-coding RNAs, and the CRISPR/Cas9 gene-editing system, have shown great potential for FH therapy. However, the delivery system, immunogenicity, accuracy, and specificity of gene therapies limit their clinical applications. In this article, we discuss the current status of gene therapy and recent advances that will likely affect the clinical application of gene therapy for the treatment of FH.