Introduction
Rosuvastatin is a lipid-lowering medication belonging to the statin class. It works by competitively inhibiting HMG-CoA reductase, the key enzyme involved in cholesterol synthesis in the liver, thereby reducing total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides while increasing high-density lipoprotein (HDL) cholesterol.
Rosuvastatin is used to treat dyslipidemia and to reduce the risk of cardiovascular events such as heart attack and stroke in patients with or at high risk of cardiovascular disease. It is considered a first-line therapy for lowering LDL cholesterol and has a relatively low potential for drug-drug interactions due to its limited metabolism by the cytochrome P450 system.
Uses
Rosuvastatin is an HMG-CoA reductase inhibitor used to lower lipid levels and reduce the risk of cardiovascular disease including myocardial infarction and stroke.
The FDA monograph states that rosuvastatin is indicated as an adjunct to diet in the treatment of triglyceridemia, Primary Dysbetalipoproteinemia (Type III Hyperlipoproteinemia), and Homozygous Familial Hypercholesterolemia.
The Health Canada monograph for rosuvastatin further specifies that rosuvastatin is indicated for the reduction of elevated total cholesterol (Total-C), LDL-C, ApoB, the Total-C/HDL-C ratio and triglycerides (TG) and for increasing HDL-C in hyperlipidemic and dyslipidemic conditions when response to diet and exercise alone has been inadequate. It is also indicated for the prevention of major cardiovascular events (including risk of myocardial infarction, nonfatal stroke, and coronary artery revascularization) in adult patients without documented history of cardiovascular or cerebrovascular events, but with at least two conventional risk factors for cardiovascular disease.
Prescribing of statin medications is considered standard practice following any cardiovascular events and for people with a moderate to high risk of development of CVD. Statin-indicated conditions include diabetes mellitus, clinical atherosclerosis (including myocardial infarction, acute coronary syndromes, stable angina, documented coronary artery disease, stroke, trans ischemic attack (TIA), documented carotid disease, peripheral artery disease, and claudication), abdominal aortic aneurysm, chronic kidney disease, and severely elevated LDL-C levels.
Associated Conditions
Pharmacodynamics
Rosuvastatin is a synthetic, enantiomerically pure antilipemic agent. It is used to lower total cholesterol, low density lipoprotein-cholesterol (LDL-C), apolipoprotein B (apoB), non-high density lipoprotein-cholesterol (non-HDL-C), and trigleride (TG) plasma concentrations while increasing HDL-C concentrations. High LDL-C, low HDL-C and high TG concentrations in the plasma are associated with increased risk of atherosclerosis and cardiovascular disease. The total cholesterol to HDL-C ratio is a strong predictor of coronary artery disease and high ratios are associated with higher risk of disease. Increased levels of HDL-C are associated with lower cardiovascular risk. By decreasing LDL-C and TG and increasing HDL-C, rosuvastatin reduces the risk of cardiovascular morbidity and mortality.
Elevated cholesterol levels, and in particular, elevated low-density lipoprotein (LDL) levels, are an important risk factor for the development of CVD. Use of statins to target and reduce LDL levels has been shown in a number of landmark studies to significantly reduce the risk of development of CVD and all-cause mortality. Statins are considered a cost-effective treatment option for CVD due to their evidence of reducing all-cause mortality including fatal and non-fatal CVD as well as the need for surgical revascularization or angioplasty following a heart attack. Evidence has shown that even for low-risk individuals (with 19,20
Skeletal Muscle Effects
Cases of myopathy and rhabdomyolysis with acute renal failure secondary to myoglobinuria have been reported with HMG-CoA reductase inhibitors, including rosuvastatin. These risks can occur at any dose level, but are increased at the highest dose (40 mg). Rosuvastatin should be prescribed with caution in patients with predisposing factors for myopathy (e.g., age ≥ 65 years, inadequately treated hypothyroidism, renal impairment).
The risk of myopathy during treatment with rosuvastatin may be increased with concurrent administration of some other lipid-lowering therapies (such as fenofibrate or niacin), gemfibrozil, cyclosporine, atazanavir/ritonavir, lopinavir/ritonavir, or simeprevir. Cases of myopathy, including rhabdomyolysis, have been reported with HMG-CoA reductase inhibitors, including rosuvastatin, coadministered with colchicine, and caution should therefore be exercised when prescribing these two medications together.
Real-world data from observational studies has suggested that 10-15% of people taking statins may experience muscle aches at some point during treatment.
Liver Enzyme Abnormalities
Increases in serum transaminases have been reported with HMG-CoA reductase inhibitors, including rosuvastatin. In most cases, the elevations were transient and resolved or improved on continued therapy or after a brief interruption in therapy. There were two cases of jaundice, for which a relationship to rosuvastatin therapy could not be determined, which resolved after discontinuation of therapy. There were no cases of liver failure or irreversible liver disease in these trials.
Endocrine Effects
Increases in HbA1c and fasting serum glucose levels have been reported with HMG-CoA reductase inhibitors, including rosuvastatin calcium tablets. Based on clinical trial data with rosuvastatin, in some instances these increases may exceed the threshold for the diagnosis of diabetes mellitus.
An in vitro study found that atorvastatin, pravastatin, rosuvastatin, and pitavastatin exhibited a dose-dependent cytotoxic effect on human pancreas islet β cells, with reductions in cell viability of 32, 41, 34 and 29%, respectively, versus control]. Moreover, insulin secretion rates were decreased by 34, 30, 27 and 19%, respectively, relative to control.
HMG-CoA reductase inhibitors interfere with cholesterol synthesis and lower cholesterol levels and, as such, might theoretically blunt adrenal or gonadal steroid hormone production. Rosuvastatin demonstrated no effect upon nonstimulated cortisol levels and no effect on thyroid metabolism as assessed by TSH plasma concentration. In rosuvastatin treated patients, there was no impairment of adrenocortical reserve and no reduction in plasma cortisol concentrations. Clinical studies with other HMG-CoA reductase inhibitors have suggested that these agents do not reduce plasma testosterone concentration. The effects of HMG-CoA reductase inhibitors on male fertility have not been studied. The effects, if any, on the pituitarygonadal axis in premenopausal women are unknown.
Cardiovascular
Ubiquinone levels were not measured in rosuvastatin clinical trials, however significant decreases in circulating ubiquinone levels in patients treated with other statins have been observed. The clinical significance of a potential long-term statin-induced deficiency of ubiquinone has not been established. It has been reported that a decrease in myocardial ubiquinone levels could lead to impaired cardiac function in patients with borderline congestive heart failure.
Lipoprotein A
In some patients, the beneficial effect of lowered total cholesterol and LDL-C levels may be partly blunted by a concomitant increase in the Lipoprotein(a) [Lp(a)] concentrations. Present knowledge suggests the importance of high Lp(a) levels as an emerging risk factor for coronary heart disease. It is thus desirable to maintain and reinforce lifestyle changes in high-risk patients placed on rosuvastatin therapy. Further studies have demonstrated statins affect Lp(a) levels differently in patients with dyslipidemia depending on their apo(a) phenotype; statins increase Lp(a) levels exclusively in patients with the low molecular weight apo(a) phenotype.
Mechanism of Action
Rosuvastatin is a statin medication and a competitive inhibitor of the enzyme HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase, which catalyzes the conversion of HMG-CoA to mevalonate, an early rate-limiting step in cholesterol biosynthesis. Rosuvastatin acts primarily in the liver, where decreased hepatic cholesterol concentrations stimulate the upregulation of hepatic low density lipoprotein (LDL) receptors which increases hepatic uptake of LDL. Rosuvastatin also inhibits hepatic synthesis of very low density lipoprotein (VLDL). The overall effect is a decrease in plasma LDL and VLDL.
In vitro and in vivo animal studies also demonstrate that rosuvastatin exerts vasculoprotective effects independent of its lipid-lowering properties, also known as the pleiotropic effects of statins. This includes improvement in endothelial function, enhanced stability of atherosclerotic plaques, reduced oxidative stress and inflammation, and inhibition of the thrombogenic response.
Statins have also been found to bind allosterically to β2 integrin function-associated antigen-1 (LFA-1), which plays an important role in leukocyte trafficking and in T cell activation.
Rosuvastatin exerts an anti-inflammatory effect on rat mesenteric microvascular endothelium by attenuating leukocyte rolling, adherence and transmigration. The drug also modulates nitric oxide synthase (NOS) expression and reduces ischemic-reperfusion injuries in rat hearts. Rosuvastatin increases the bioavailability of nitric oxide by upregulating NOS and by increasing the stability of NOS through post-transcriptional polyadenylation. It is unclear as to how rosuvastatin brings about these effects though they may be due to decreased concentrations of mevalonic acid.
Absorption
In a study of healthy white male volunteers, the absolute oral bioavailability of rosuvastatin was found to be approximately 20% while absorption was estimated to be 50%, which is consistent with a substantial first-pass effect after oral dosing. Another study in healthy volunteers found that the peak plasma concentration (Cmax) of rosuvastatin was 6.06ng/mL and was reached at a median of 5 hours following oral dosing. Both Cmax and AUC increased in approximate proportion to dose. Neither food nor evening versus morning administration was shown to have an effect on the AUC of rosuvastatin. Many statins are known to interact with hepatic uptake transporters and thus reach high concentrations at their site of action in the liver.
Breast Cancer Resistance Protein (BCRP) is a membrane-bound protein that plays an important role in the absorption of rosuvastatin, particularly as CYP3A4 has minimal involvement in its metabolism. Evidence from pharmacogenetic studies of c.421C>A single nucleotide polymorphisms (SNPs) in the gene for BCRP has demonstrated that individuals with the 421AA genotype have reduced functional activity and 2.4-fold higher AUC and Cmax values for rosuvastatin compared to study individuals with the control 421CC genotype. This has important implications for the variation in response to the drug in terms of efficacy and toxicity, particularly as the BCRP c.421C>A polymorphism occurs more frequently in Asian populations than in Caucasians. Other statin drugs impacted by this polymorphism include fluvastatin and atorvastatin.
Genetic differences in the OATP1B1 (organic-anion-transporting polypeptide 1B1) hepatic transporter have also been shown to impact rosuvastatin pharmacokinetics. Evidence from pharmacogenetic studies of the c.521T>C SNP showed that rosuvastatin AUC was increased 1.62-fold for individuals homozygous for 521CC compared to homozygous 521TT individuals. Other statin drugs impacted by this polymorphism include simvastatin, pitavastatin, atorvastatin, and pravastatin.
For patients known to have the above-mentioned c.421AA BCRP or c.521CC OATP1B1 genotypes, a maximum daily dose of 20mg of rosuvastatin is recommended to avoid adverse effects from the increased exposure to the drug, such as muscle pain and risk of rhabdomyolysis.
Volume of Distribution
Rosuvastatin undergoes first-pass extraction in the liver, which is the primary site of cholesterol synthesis and LDL-C clearance. The mean volume of distribution at steady-state of rosuvastatin is approximately 134 litres.
Protein Binding
Rosuvastatin is 88% bound to plasma proteins, mostly albumin. This binding is reversible and independent of plasma concentrations.
Route of Elimination
Rosuvastatin is not extensively metabolized; approximately 10% of a radiolabeled dose is recovered as metabolite. Following oral administration, rosuvastatin and its metabolites are primarily excreted in the feces (90%). After an intravenous dose, approximately 28% of total body clearance was via the renal route, and 72% by the hepatic route.
A study in healthy adult male volunteers found that approximately 90% of the rosuvastatin dose was recovered in feces within 72 hours after dose, while the remaining 10% was recovered in urine. The drug was completely excreted from the body after 10 days of dosing. They also found that approximately 76.8% of the excreted dose was unchanged from the parent compound, with the remaining dose recovered as the metabolites n-desmethyl rosuvastatin and rosuvastatin-5S-lactone.
Renal tubular secretion is responsible for >90% of total renal clearance, and is believed to be mediated primarily by the uptake transporter OAT3 (Organic anion transporter 1), while OAT1 had minimal involvement.
Half Life
The elimination half-life (t½) of rosuvastatin is approximately 19 hours and does not increase with increasing doses.
Toxicity
Generally well-tolerated. Side effects may include myalgia, constipation, asthenia, abdominal pain, and nausea. Other possible side effects include myotoxicity (myopathy, myositis, rhabdomyolysis) and hepatotoxicity. To avoid toxicity in Asian patients, lower doses should be considered. Pharmacokinetic studies show an approximately two-fold increase in peak plasma concentration and AUC in Asian patients (Philippino, Chinese, Japanese, Korean, Vietnamese, or Asian-Indian descent) compared to Caucasian patients.
Food Interactions
- Take with or without food. Co-administration with food does not affect absorption.
Dosage
Very High Cholesterol and High Risk of Ml or Stroke: 40 mg once daily.
Homozygous Familial Hypercholesterolemia: The recommended starting dose of Rosuvastatin is 20 mg once daily. Response to therapy should be estimated from preapheresis LDL-C levels.
Dosage in Asian Patients: Initiation of Rosuvastatin therapy with 5 mg once daily should be considered for Asian patients
Use with Cyclosporine, Lopinavir/Ritonavir or Atazanavir/Ritonavir: In patients taking Cyclosporine, the dose of Rosuvastatin should be limited to 5 mg once daily. In patients taking a combination of Lopinavir and Ritonavir or Atazanavir and Ritonavir, the dose of Rosuvastatin should be limited to 10 mg once daily.
Concomitant Lipid-Lowering Therapy: The risk of skeletal muscle effects may be enhanced when Rosuvastatin is used in combination with Niacin or Fenofibrate; a reduction in Rosuvastatin dosage should be considered in this setting. Combination therapy with Gemfibrozil should be avoided because of an increase in Rosuvastatin exposure with concomitant use; if Rosuvastatin is used in combination with Gemfibrozil, the dose of Rosuvastatin should be limited to 10 mg once daily.
Dosage in Patients with Severe Renal Impairment: For patients with severe renal impairment (ClCr<30 mL/min/1.73 m²) not on hemodialysis, dosing of Rosuvastatin should be started at 5 mg once daily and not exceed 10 mg once daily.