Evinacumab: a new option in the treatment of homozygous familial hypercholesterolemia.

INTRODUCTION: Familial hypercholesterolemia is a genetic disorder characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C) since birth and an exceedingly high risk of premature cardiovascular disease, especially in the homozygous form (HoFH). Despite the availability of effective cholesterol-lowering drugs, substantial LDL-C and cardiovascular risk reductions in these patients are still problematic, especially in those carrying mutations in the low-density lipoprotein receptor (LDLR) gene. AREAS COVERED: Loss-of-function mutations in angiopoietin-like 3 (ANGPTL3) encoding gene are associated with lower levels of LDL-C and reduced cardiovascular risk; the pharmacological inhibition of ANGPTL3 reduces LDL-C levels independently of LDLR. This approach can thus improve the treatment of HoFH using a monoclonal antibody targeting ANGPTL3 (evinacumab). EXPERT OPINION: Most lipid-lowering agents available so far are insufficient to achieve an appropriate response in HoFH patients. The inhibition of ANGPTL3 with evinacumab halves LDL-C levels in HoFH patients by an LDLR-independent mechanism. The results obtained so far have clearly indicated a promising improvement in the management of these patients. As the reduction of CV risk is proportional to the absolute reduction in LDL-C levels, we can expect that treatment with evinacumab, added to the maximally tolerated lipid-lowering therapy, will turn into a significant clinical benefit.

Intraindividual Comparisons to Determine Comparative Effectiveness: Their Relevance for G-BA's Health Technology Assessments.

OBJECTIVES: Health technology assessments (HTA) rely on head-to-head comparisons. We searched for intraindividual comparisons (IIC) qualifying as head-to-head design to develop comparative evidence. METHODS: Gemeinsamer Bundesausschuss (G-BA) appraisals between January 2011 and April 2020 were reviewed for inclusion of IIC. Identified IIC were grouped according to disease characteristics into nonprogressive, progressive, irregular, or symmetrical conditions. Evaluation of IIC by Institut für Qualität und Wirschaftlichkeit im Gesundheitswesen (IQWIG) and acceptance of IIC by G-BA were determined, and criteria for the usage and quality of IIC were developed. RESULTS: A total of 483 appraisals finalized between January 2011 and April 2020 were reviewed. Eleven appraisals included IIC: nonacog beta (hemophilia B), turoctocog alpha (hemophilia A), emicizumab (2 appraisals: hemophilia A), pasireotide (unresectable pituitary tumor), lomitapid (homozygous familial hypercholesterolemia), glycerol phenylbutyrate (2 appraisals: urea cycle disorders), asfotase alfa (hypophosphatasia), lumacaftor (cystic fibrosis), and larotrectinib (NTRK+ solid tumors). All those appraisals related to rare genetic conditions with hemophilia and its bleeding rate are considered mainly a nonprogressive condition. All the other diseases show progressive disease characteristics. None of the identified IIC has been accepted by G-BA. Inconsistencies of before/after study design, lack of clarity on treatments prior to the switch, and different time intervals were among the most commonly cited methodological concerns. CONCLUSIONS: IICs provide a rare opportunity to determine comparative effectiveness in distinct clinical settings that are not suitable or difficult to randomize into parallel groups. While manufacturers and researchers should aim for highest methodological standards when running an IIC, HTA bodies should accept IIC in distinct settings when determining relative effectiveness.

Homozygous Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is an inherited disorder with retarded clearance of plasma LDL caused by mutations of the genes involved in the LDL receptor-mediated pathway and most of them exhibit autosomal dominant inheritance. Homozygotes of FH (HoFH) may have plasma LDL-C levels, which are at least twice as high as those of heterozygous FH (HeFH) and therefore four times higher than normal levels. Prevalence of HoFH had been estimated as 1 in 1,000,000 before but more recent genetic analysis surveys predict 1 in 170,000 to 300,000. Since LDL receptor activity is severely impaired, HoFH patients do not or very poorly respond to medications to enhance activity, such as statins, and have a poorer prognosis compared to HeFH. HoFH should therefore be clinically distinguished from HeFH. Thorough family studies and genetic analysis are recommended for their accurate diagnosis.Fatal cardiovascular complications could develop even in the first decade of life for HoFH, so aggressive lipid-lowering therapy should be initiated as early as possible. Direct removal of plasma LDL by lipoprotein apheresis has been the principal measure for these patients. However, this treatment alone may not achieve stable LDL-C target levels and combination with drugs should be considered. The lipid-lowering effects of statins and PCSK9 inhibitors substantially vary depending on the remaining LDL receptor activity of individual patients. On the other hand, the action an MTP inhibitor is independent of LDL receptor activity, and it is effective in most HoFH cases.This review summarizes the key clinical issues of HoFH as well as insurance coverage available under the Japanese public healthcare system.