Claudia Stefanutti

Efficacy and safety of a microsomal triglyceride transfer protein inhibitor in patients with homozygous familial hypercholesterolaemia: a single-arm, open-label, phase 3 study

BACKGROUND Patients with homozygous familial hypercholesterolaemia respond inadequately to existing drugs. We aimed to assess the efficacy and safety of the microsomal triglyceride transfer protein inhibitor lomitapide in adults with this disease. METHODS We did a single-arm, open-label, phase 3 study of lomitapide for treatment of patients with homozygous familial hypercholesterolemia. Current lipid lowering therapy was maintained from 6 weeks before baseline through to at least week 26. Lomitapide dose was escalated on the basis of safety and tolerability from 5 mg to a maximum of 60 mg a day. The primary endpoint was mean percent change in levels of LDL cholesterol from baseline to week 26, after which patients remained on lomitapide through to week 78 for safety assessment. Percent change from baseline to week 26 was assessed with a mixed linear model. FINDINGS 29 men and women with homozygous familial hypercholesterolaemia, aged 18 years or older, were recruited from 11 centres in four countries (USA, Canada, South Africa, and Italy). 23 of 29 enrolled patients completed both the efficacy phase (26 weeks) and the full study (78 weeks). The median dose of lomitapide was 40 mg a day. LDL cholesterol was reduced by 50% (95% CI -62 to -39) from baseline (mean 8·7 mmol/L [SD 2·9]) to week 26 (4·3 mmol/L [2·5]; p<0·0001). Levels of LDL cholesterol were lower than 2·6 mmol/L in eight patients at 26 weeks. Concentrations of LDL cholesterol remained reduced by 44% (95% CI -57 to -31; p<0·0001) at week 56 and 38% (-52 to -24; p<0·0001) at week 78. Gastrointestinal symptoms were the most common adverse event. Four patients had aminotransaminase levels of more than five times the upper limit of normal, which resolved after dose reduction or temporary interruption of lomitapide. No patient permanently discontinued treatment because of liver abnormalities. INTERPRETATION Our study suggests that treatment with lomitapide could be a valuable drug in the management of homozygous familial hypercholesterolaemia. FUNDING FDA Office of the Orphan Product Development, Aegerion Pharmaceuticals.

Lipoprotein apheresis: State of the art and novelties

Lipoprotein apheresis (LA) is an extracorporeal technique which permits the unselective or specific removal of lipoproteins, namely Low Density Lipoproteins (LDL), as well as other apolipoprotein B100-containing lipoproteins from plasma. LA represents a selective upgrade (with both clinical and metabolic advantages) from conventional forms of extracorporeal therapy such as plasma-exchange (PEX) which was used in the seventies to treat severe hypercholesterolemia. The primary reason for using is the treatment of homo-, double- (or compound) and heterozygous familial hypercholesterolemia (Hoz-, DHtz,- Htz,-FH). This technique has also been shown to be efficacious in the treatment of other severe forms of hyperlipoproteinemia such as: hyperLp(a)lipoproteinemia, the familial combined hyperlipoproteinemia and other varieties associated with an elevated cardiovascular risk (CVR) when used in patients who are poor- or non-responders to pharmacological treatment following specific guidelines for the reduction of cholesterol in plasma. Patients with these severe forms of dyslipidemia and, particularly, those affected by FH are subject to coronary ischemic events and thus require an intensive, efficacious, continuous, and personalized form of therapy. A therapy based solely on current available drugs does not achieve the desired results in the Hoz- and DHtz forms of FH or in approximately 10-20% of the Htz form. For the aforementioned clinical conditions, LA treatment offers a necessary therapeutic approach. LA can also be applied in the prevention of secondary recurrence of coronary ischemic events and of arterial stenosis which appears, rather frequently after vascular surgery (coronary by-pass, percutaneous transluminal angioplasty). Clinical trials have shown that statins provide a major reduction in cardiovascular morbidity and mortality, but often fail to attain desirable LDL-cholesterol target level in Hoz- and DHtz- (Compound) FH high cardiovascular risk patients. Intolerance to statins is also relatively frequent in Htz-FH and non-FH patients. LA has effectively replaced pharmacological cholesterol-lowering therapy for decades. Young high CVR risk patients survived to adulthood thanks only to LA. More recently, promising novel compounds aimed at other molecular targets are being studied for the treatment of severe dyslipidemia: Lomitapide, Mipomersen, PCSK9 inhibitors and HDL-enhancers. It is expected that these potent new agents will be combined with LA in the treatment of the most severe forms of hyperlipidemia.

Severe Hypertriglyceridemia-Related Acute Pancreatitis

Acute pancreatitis is a potentially life‐threatening complication of severe hypertriglyceridemia. In some cases, inborn errors of metabolism such as lipoprotein lipase deficiency, apoprotein C‐II deficiency, and familial hypertriglyceridemia have been reported as causes of severe hypertriglyceridemia. More often, severe hypertriglyceridemia describes various clinical conditions characterized by high plasma levels of triglycerides (>1000 mg/dL), chylomicron remnants, or intermediate density lipoprotein like particles, and/or chylomicrons. International guidelines on the management of acute pancreatitis are currently available. Standard therapeutic measures are based on the use of lipid‐lowering agents (fenofibrate, gemfibrozil, niacin, Ω‐3 fatty acids), low molecular weight heparin, and insulin in diabetic patients. However, when standard medical therapies have failed, non‐pharmacological approaches based upon the removal of triglycerides with therapeutic plasma exchange can also provide benefit to patients with severe hypertriglyceridemia and acute pancreatitis. Plasma exchange could be very helpful in reducing triglycerides levels during the acute phase of hyperlipidemic pancreatitis, and in the prevention of recurrence. The current evidence on management of acute pancreatitis and severe hypertriglyceridemia, focusing on symptoms, treatment and potential complications is reviewed herein.

Lipid and low-density-lipoprotein apheresis. Effects on plasma inflammatory profile and on cytokine pattern in patients with severe dyslipidemia

Available evidence on the effects of therapeutic plasmapheresis (TP) techniques and in particular lipid- and LDL-apheresis (LDL-a) on plasmatic inflammatory mediators including cytokines were reviewed. Studies on this issue are not numerous. However, the review of existing evidence clearly suggests an active role of apheresis on the profile of inflammatory molecules and on cytokine pattern in plasma. These non-lipid-lowering effects can be defined to some extent pleiotropic or pleiotropic-equivalent. Although further studies are desirable, the data reported in this review confirm that lipid- and LDL-a not only show acute lipid-lowering and cholesterol-lowering effects, but also efficacy in reducing several proinflammatory peptides, including cytokines. This effect was not related apparently to lipids and lipoproteins reduction. Thus, TP (lipid- and LDL-a), commonly utilized in the treatment of severe genetically determined lipid disorders, unresponsive to hypolipidemic drugs, offers new possibilities of interpretation of its role in the mechanisms leading to the blockade of atherosclerotic lesion development and progression. The ability of TP on short-term to induce such a profound change in the plasmatic metabolic and inflammatory profiles must be kept in mind in the treatment of acute coronary syndromes, before and after interventions of coronary revascularization, and in the acute phase of cerebrovascular ischemia, at least in patients with severe dyslipidemia. Further studies are needed, in particular aimed at assessing if circulating cytokines may be downregulated by TP not only by direct removal, but through indirect effects on both gene translation and transcription perhaps via the cytokine receptor function.

The effect of an apolipoprotein A-I–containing high-density lipoprotein–mimetic particle (CER-001) on carotid artery wall thickness in patients with homozygous familial hypercholesterolemia: The Modifying Orphan Disease Evaluation (MODE) study

BACKGROUND Patients with homozygous familial hypercholesterolemia (HoFH) are at extremely elevated risk for early cardiovascular disease because of exposure to elevated low-density lipoprotein cholesterol (LDL-C) plasma levels from birth. Lowering LDL-C by statin therapy is the cornerstone for cardiovascular disease prevention, but the residual risk in HoFH remains high, emphasizing the need for additional therapies. In the present study, we evaluated the effect of serial infusions with CER-001, a recombinant human apolipoprotein A-I (apoA-I)-containing high-density lipoprotein-mimetic particle, on carotid artery wall dimensions in patients with HoFH. METHODS AND RESULTS Twenty-three patients (mean age 39.4 ± 13.5 years, mean LDL-C 214.2 ± 81.5 mg/dL) with genetically confirmed homozygosity or compound heterozygosity for LDLR, APOB, PCSK9, or LDLRAP1 mutations received 12 biweekly infusions with CER-001 (8 mg/kg). Before and 1 hour after the first infusion, lipid values were measured. Magnetic resonance imaging (3-T magnetic resonance imaging) scans of the carotid arteries were acquired at baseline and after 24 weeks to assess changes in artery wall dimensions. After CER-001 infusion, apoA-I increased from 114.8 ± 20.7 mg/dL to 129.3 ± 23.0 mg/dL. After 24 weeks, mean vessel wall area (primary end point) decreased from 17.23 to 16.75 mm(2) (P = .008). A trend toward reduction of mean vessel wall thickness was observed (0.75 mm at baseline and 0.74 mm at follow-up, P = .0835). CONCLUSIONS In HoFH, 12 biweekly infusions with an apoA-I-containing high-density lipoprotein-mimetic particle resulted in a significant reduction in carotid mean vessel wall area, implying that CER-001 may reverse atherogenic changes in the arterial wall on top of maximal low-density lipoprotein-lowering therapy. This finding supports further clinical evaluation of apoA-I-containing particles in patients with HoFH.

Cytokines profile in serum of homozygous familial hypercholesterolemia is changed by LDL-apheresis

OBJECTIVE The effects of LDL-apheresis (LDLa) with dextran sulphate on plasma cytokines in 6 homozygous familial hypercholesterolemic (HozFH) patients, were evaluated. METHODS Plasma IL-1α; IL-1ra; IL-4; IL-6; IL-10; IL-12(p40); IL-12(p70); TNF-α, sTNF-R, VEGF, VEGF-R1, E-Selectin (ESEL), and P-Selectin (PSEL) concentrations were measured before and after LDLa on three consecutive sessions for each patient. RESULTS TNF-α was significantly reduced (-60%; P=0.01), while TNF-R was only slightly increased (+15%), although not significantly. Plasma VEGF was significantly reduced (-57%; P=1.87301E-05), while VEGF-R1 was significantly increased (+56%; P=0.05). ESEL and PSEL were reduced but not to a statistically significant extent (-19%, -15%, respectively). IL-1α level was dramatically reduced (-87%; P=0.0001). IL-1ra concentration was only slightly increased in plasma, but not significantly. IL-4 and IL-10 levels were significantly reduced in plasma after apheresis (-50%; P=0.03, and -55%; P=0.004, respectively). On the contrary, IL-6 concentration showed a slight decrease (-8%). Plasma IL-12p40 was significantly increased (+47%; P=0.0004). On the other hand, IL-12p70 was reduced, but the difference (-31%) was not statistically significant. CONCLUSIONS Plasma cytokines imbalance is associated with inflammation and atherogenesis. In this study LDLa changed several circulating cytokines inducing anti-inflammatory and anti-atherogenic changes in cytokines plasma profile in HozFH patients with/without pre-existing angiographically demonstrated coronary heart disease (CHD) and aortic valvular disease (AVD).

Homozygous autosomal dominant hypercholesterolaemia: prevalence, diagnosis, and current and future treatment perspectives.

Purpose of review Homozygous autosomal dominant hypercholesterolemia (hoADH) is a rare genetic disorder caused by mutations in LDL receptor, apolipoprotein B, and/or proprotein convertase subtilisin-kexin type 9. Both the genetic mutations and the clinical phenotype vary largely among individual patients, but patients with hoADH are typically characterized by extremely elevated LDL-cholesterol (LDL-C) levels, and a very high-risk for premature cardiovascular disease. Current lipid-lowering therapies include bile acid sequestrants, statins, and ezetimibe. To further decrease LDL-C levels in hoADH, lipoprotein apheresis is recommended, but this therapy is not available in all countries. Recent findings Recently, the microsomal triglyceride transfer protein inhibitor lomitapide and the RNA antisense inhibitor of apolipoprotein B mipomersen were approved by the Food and Drug Administration/European Medicine Agency and the Food and Drug Administration, respectively. Several other LDL-C-lowering strategies and therapeutics targeting the HDL-C pathway are currently in the clinical stage of development. Summary Novel therapies have been introduced for LDL-C-lowering and innovative drug candidates for HDL-C modulation for the treatment of hoADH. Here, we review the current available literature on the prevalence, diagnosis, and therapeutic strategies for hoADH.

Treatment of symptomatic hyperLp(a)lipidemia with LDL-apheresis vs. usual care

BACKGROUND/AIMS To assess LDL-apheresis efficacy to lower Lp(a) and to compare the effects of Usual Medical Care (UMC) a 12-months study was carried out. The incidence of new coronary artery disease (CAD) events/need of revascularization, was also monitored. METHODS Twenty-one patients with hyperLp(a)lipidemia and angiographically documented CAD were randomly assigned to LDL-apheresis every week, or the UMC. RESULTS LDL-apheresis group, averaged an Lp(a) reduction of 57.8+/-9.5% vs. basal values (P<0.001). In the UMC group Lp(a) increased in 1 year to 14.7+/-36.5% (P=0.66). Stepwise multivariate regression analysis for predictors of Lp(a) including: type of treatment, smoking, hypertension, age, age at first cardiovascular event, initial Lp(a), LDL, and BMI values, was performed. Only the type of treatment was co-related (P<0.001): Lp(a) variation (beta)=0.863. The model has R2 adjusted relative risk of 0.725. CONCLUSION LDL-apheresis could be the first line treatment of isolated hyperLp(a)lipidemia when CAD is established. New CAD events/cardiac interventions were not observed.

Aorta and coronary angiographic follow-up of children with severe hypercholesterolemia treated with low-density lipoprotein apheresis

BACKGROUND: In this single‐center, nonrandomized, prospective study, 11 children with severe genetic hypercholesterolemia, without previous cardiovascular disease events, were treated with low‐density lipoprotein apheresis (LDLa).

The Italian Registry of Pediatric Therapeutic Apheresis: A report on activity during 2005

The results of the 2005 Survey of the Italian Society for Apheresis and Cell Manipulation (SIdEM) reporting on the pediatric procedures carried out in 18 Italian Apheresis Units are presented here. Utilizing a standardized questionnaire, the survey collected data on techniques, types of blood separators, clinical indications, and adverse events. A total of 1,693 apheresis procedures were carried out in 355 pediatric patients: 219 plasma‐exchange, 291 peripheral blood stem cell collections, 791 extracorporeal photochemotherapy (ECP), 265 LDL‐apheresis, 71 erythro‐exchange, 9 cytoreductive apheresis, 47 immunoadsorption sessions. Adverse events were registered in 94 procedures (5.6%), most of which of mild entity, e.g., insufficient flow rate (50.0%) and symptomatic hypocalcemia (24.4%). Our data indicate that all types of apheresis procedures can be safely carried out in children. ECP, utilized primarily for the treatment of graft versus host disease (GvHD) and rejection of solid organ transplantation, are burgeoning procedures in pediatric patients, whereas plasma exchange, which is a common treatment in adults, is infrequently utilized in pediatric medicine. J. Clin. Apheresis, 2009.