SIMVASTATIN Drug Interactions: What You Need to Know

INTERACTIONS

• See full prescribing information for details regarding concomitant use of simvastatin with other drugs or grapefruit juice that increase the risk of myopathy and rhabdomyolysis. ( Error! Hyperlink reference not valid. , Error! Hyperlink reference not valid. )
• Coumarin Anticoagulants: Obtain INR before simvastatin initiation and monitor INR during simvastatin dosage initiation or adjustment. ( Error! Hyperlink reference not valid. )
• Digoxin: During simvastatin initiation, monitor digoxin levels. ( Error! Hyperlink reference not valid. )

7.1 Drug Interactions that Increase the Risk of Myopathy and Rhabdomyolysis with Simvastatin Simvastatin is a substrate of CYP3A4 and of the transport protein OATP1B1. Simvastatin exposure can be significantly increased with concomitant administration of inhibitors of CYP3A4 and OATP1B1.

Table

2 includes a list of drugs that increase the risk of myopathy and rhabdomyolysis when used concomitantly with simvastatin and instructions for preventing or managing them [see WARNINGS AND PRECAUTIONS ( Error! Hyperlink reference not valid. ) AND CLINICAL PHARMACOLOGY ( Error! Hyperlink reference not valid. )] .

Table

2: Drug Interactions that Increase the Risk of Myopathy and Rhabdomyolysis with Simvastatin Strong CYP3A4 inhibitors Clinical Impact: Simvastatin is a substrate of CYP3A4. Concomitant use of strong CYP3A4 inhibitors with simvastatin increases simvastatin exposure and increases the risk of myopathy and rhabdomyolysis, particularly with higher simvastatin dosages. Intervention: Concomitant use of strong CYP3A4 inhibitors with Simvastatin is contraindicated [see CONTRAINDICATIONS ( Error! Hyperlink reference not valid. )] . If treatment with a CYP3A4 inhibitor is unavoidable, suspend simvastatin during the course of strong CYP3A4 inhibitor treatment. Examples: Select azole anti-fungals (e.g., itraconazole, ketoconazole, posaconazole, and voriconazole), select macrolide antibiotics (e.g., erythromycin and clarithromycin), select HIV protease inhibitors (e.g., nelfinavir, ritonavir, and darunavir/ritonavir), select HCV protease inhibitors (e.g., boceprevir and telaprevir), cobicistat-containing products, and nefazodone. Cyclosporine, Danazol, or Gemfibrozil Clinical Impact: The risk of myopathy and rhabdomyolysis is increased with concomitant use of cyclosporine, danazol, or gemfibrozil with simvastatin. Gemfibrozil may cause myopathy when given alone. Intervention: Concomitant use of cyclosporine, danazol, or gemfibrozil with simvastatin is contraindicated [see CONTRAINDICATIONS ( Error! Hyperlink reference not valid. )] . Amiodarone, Dronedarone, Ranolazine, or Calcium Channel Blockers Clinical Impact: The risk of myopathy and rhabdomyolysis is increased by concomitant use of amiodarone, dronedarone, ranolazine, or calcium channel blockers with simvastatin. Intervention: For patients taking verapamil, diltiazem, or dronedarone, do not exceed simvastatin 10 mg daily. For patients taking amiodarone, amlodipine, or ranolazine, do not exceed simvastatin 20 mg daily [see DOSAGE AND ADMINISTRATION ( Error! Hyperlink reference not valid. )] .

Lomitapide Clinical

Impact: Simvastatin exposure is approximately doubled with concomitant use of lomitapide and the risk of myopathy and rhabdomyolysis is increased. Intervention: Reduce the dose of simvastatin by 50% if initiating lomitapide. Do not exceed simvastatin 20 mg daily (or simvastatin 40 mg daily for patients who have previously taken simvastatin 80 mg daily chronically) while taking lomitapide [see DOSAGE AND ADMINISTRATION ( 2.1 , Error! Hyperlink reference not valid. )] .

Daptomycin Clinical

Impact: Cases of rhabdomyolysis have been reported with simvastatin administered with daptomycin. Both simvastatin and daptomycin can cause myopathy and rhabdomyolysis when given alone and the risk of myopathy and rhabdomyolysis may be increased by coadministration. Intervention: If treatment with daptomycin is required, consider temporarily suspending simvastatin during the course of daptomycin treatment.

Niacin Clinical

Impact: Cases of myopathy and rhabdomyolysis have been observed with concomitant use of lipid modifying dosages of niacin-containing products (≥1 gram/day niacin) with simvastatin. The risk of myopathy is greater in Chinese patients. In a clinical study (median follow-up 3.9 years) of patients at high risk of CVD and with well-controlled LDL-C levels on simvastatin 40 mg/day with or without ezetimibe 10 mg/day, there was no incremental benefit on cardiovascular outcomes with the addition of lipid-modifying doses of niacin. Intervention: Concomitant use of simvastatin with lipid-modifying dosages of niacin is not recommended in Chinese patients [see USE IN SPECIFIC POPULATIONS ( Error! Hyperlink reference not valid. )]. For non-Chinese patients, consider if the benefit of using lipid-modifying doses of niacin concomitantly with simvastatin outweighs the increased risk of myopathy and rhabdomyolysis. If concomitant use is decided, monitor patients for signs and symptoms of myopathy, particularly during initiation of therapy and during upward dose titration of either drug. Fibrates (other than Gemfibrozil)

Clinical

Impact: Fibrates may cause myopathy when given alone. The risk of myopathy and rhabdomyolysis is increased with concomitant use of fibrates with simvastatin. Intervention: Consider if the benefit of using fibrates concomitantly with simvastatin outweighs the increased risk of myopathy and rhabdomyolysis. If concomitant use is decided, monitor patients for signs and symptoms of myopathy, particularly during initiation of therapy and during upward dose titration of either drug.

Colchicine Clinical

Impact: Cases of myopathy and rhabdomyolysis have been reported with concomitant use of colchicine with simvastatin. Intervention: Consider if the benefit of using colchicine concomitantly with simvastatin outweighs the increased risk of myopathy and rhabdomyolysis. If concomitant use is decided, monitor patients for signs and symptoms of myopathy, particularly during initiation of therapy and during upward dose titration of either drug.

Grapefruit Juice Clinical

Impact: Grapefruit juice can raise the plasma levels of simvastatin and may increase the risk of myopathy and rhabdomyolysis. Intervention: Avoid grapefruit juice when taking simvastatin.

7.2 Simvastatin Effects on Other Drugs Table 3 presents Simvastatin's effect on other drugs and instructions for preventing or managing them.

Table

3: Simvastatin Effects on Other Drugs Coumarin Anticoagulants Clinical Impact: Simvastatin may potentiate the effect of coumarin anticoagulants and increase the INR. The concomitant use of simvastatin (20 to 40 mg) and coumarin anticoagulants increased the INR from a baseline of 1.7 to 1.8 in healthy subjects and from 2.6 to 3.4 in patients with hyperlipidemia. There are postmarketing reports of clinically evident bleeding and/or increased INR in patients taking concomitant statins and warfarin. Intervention: In patients taking coumarin anticoagulants, obtain an INR before starting simvastatin and frequently enough after initiation, dose titration, or discontinuation to ensure that no significant alteration in INR occurs. Once the INR is stable, monitor INR at regularly recommended intervals.

Digoxin Clinical

Impact: Concomitant use of digoxin with simvastatin may result in elevated plasma digoxin concentrations [ see CLINICAL PHARMACOLOGY ( 12.3 ) ]. Intervention: Monitor digoxin levels in patients taking digoxin when simvastatin is initiated.

Concomitant administration of strong CYP3A4 inhibitors. ( 4 , 5.1 ) Concomitant administration of gemfibrozil, cyclosporine, or danazol. ( 4 , 5.1 ) Hypersensitivity to any component of this medication. ( 4 , 6.2 ) Active liver disease, which may include unexplained persistent elevations in hepatic transaminase levels. ( 4 , 5.2 ) Women who are pregnant or may become pregnant. ( 4 , 8.1 ) Nursing mothers. ( 4 , 8.3 ) Simvastatin is contraindicated in the following conditions:Simvastatin is contraindicated in the following conditions: Concomitant administration of strong CYP3A4 inhibitors (e.g., itraconazole, ketoconazole, posaconazole, voriconazole, HIV protease inhibitors, boceprevir, telaprevir, erythromycin, clarithromycin, telithromycin, nefazodone, and cobicistat-containing products) [see WARNINGS AND PRECAUTIONS ( 5.1 )] . Concomitant administration of strong CYP3A4 inhibitors (e.g., itraconazole, ketoconazole, posaconazole, voriconazole, HIV protease inhibitors, boceprevir, telaprevir, erythromycin, clarithromycin, telithromycin, nefazodone, and cobicistat-containing products) [see WARNINGS AND PRECAUTIONS ( 5.1 )] . Concomitant administration of gemfibrozil, cyclosporine, or danazol [see WARNINGS AND PRECAUTIONS ( 5.1 )] . Hypersensitivity to any component of this medication [see ADVERSE REACTIONS ( 6.2 )] . Active liver disease, which may include unexplained persistent elevations in hepatic transaminase levels [see WARNINGS AND PRECAUTIONS ( 5.2 )] . Women who are pregnant or may become pregnant. Serum cholesterol and triglycerides increase during normal pregnancy, and cholesterol or cholesterol derivatives are essential for fetal development. Because HMG-CoA reductase inhibitors (statins) decrease cholesterol synthesis and possibly the synthesis of other biologically active substances derived from cholesterol, simvastatin may cause fetal harm when administered to a pregnant woman. Atherosclerosis is a chronic process and the discontinuation of lipid-lowering drugs during pregnancy should have little impact on the outcome of long-term therapy of primary hypercholesterolemia. There are no adequate and well-controlled studies of use with simvastatin during pregnancy; however, in rare reports congenital anomalies were observed following intrauterine exposure to statins. In rat and rabbit animal reproduction studies, simvastatin revealed no evidence of teratogenicity. Simvastatin should be administered to women of childbearing age only when such patients are highly unlikely to conceive. If the patient becomes pregnant while taking this drug, simvastatin should be discontinued immediately and the patient should be apprised of the potential hazard to the fetus [see USE IN SPECIFIC POPULATIONS ( 8.1 )] . Nursing mothers. It is not known whether simvastatin is excreted into human milk; however, a small amount of another drug in this class does pass into breast milk. Because statins have the potential for serious adverse reactions in nursing infants, women who require treatment with simvastatin should not breastfeed their infants [see USE IN SPECIFIC POPULATIONS ( 8.3 )] .

5.

Warnings And Precautions

Patients should be advised of the increased risk of myopathy including rhabdomyolysis with the 80-mg dose. ( 5.1 ) Skeletal muscle effects (e.g., myopathy and rhabdomyolysis): Risks increase with higher doses and concomitant use of certain medicines. Predisposing factors include advanced age (≥65), female gender, uncontrolled hypothyroidism, and renal impairment. Rare cases of rhabdomyolysis with acute renal failure secondary to myoglobinuria have been reported. ( 4 , 5.1 , 8.5 , 8.6 ) Patients should be advised to report promptly any unexplained and/or persistent muscle pain, tenderness, or weakness. Simvastatin therapy should be discontinued immediately if myopathy is diagnosed or suspected.

See Drug

Interaction table. ( 5.1 ) Liver enzyme abnormalities: Persistent elevations in hepatic transaminases can occur. Check liver enzyme tests before initiating therapy and as clinically indicated thereafter. ( 5.2 )

5.1 Myopathy/Rhabdomyolysis Simvastatin occasionally causes myopathy manifested as muscle pain, tenderness or weakness with creatine kinase (CK) above ten times the upper limit of normal (ULN). Myopathy sometimes takes the form of rhabdomyolysis with or without acute renal failure secondary to myoglobinuria, and rare fatalities have occurred. The risk of myopathy is increased by elevated plasma levels of simvastatin and simvastatin acid. Predisposing factors for myopathy include advanced age (≥65 years), female gender, uncontrolled hypothyroidism, and renal impairment. Chinese patients may be at increased risk for myopathy [See Use in Specific Populations (8.8) ] . In a clinical trial database in which 41,413 patients were treated with simvastatin, 24,747 (approximately 60%) of whom were enrolled in studies with a median follow-up of at least 4 years, the incidence of myopathy was approximately 0.03% and 0.08% at 20 and 40 mg/day, respectively. The incidence of myopathy with 80 mg (0.61%) was disproportionately higher than that observed at the lower doses. In these trials, patients were carefully monitored and some interacting medicinal products were excluded The risk of myopathy, including rhabdomyolysis, is dose related. In a clinical trial database in which 41,413 patients were treated with simvastatin, 24,747 (approximately 60%) of whom were enrolled in studies with a median follow-up of at least 4 years, the incidence of myopathy was approximately 0.03% and 0.08% at 20 and 40 mg/day, respectively. The incidence of myopathy with 80 mg (0.61%) was disproportionately higher than that observed at the lower doses. In these trials, patients were carefully monitored and some interacting medicinal products were excluded In a clinical trial in which 12,064 patients with a history of myocardial infarction were treated with simvastatin (mean follow-up 6.7 years), the incidence of myopathy (defined as unexplained muscle weakness or pain with a serum creatine kinase [CK] >10 times upper limit of normal [ULN]) in patients on 80 mg/day was approximately 0.9% compared with 0.02% for patients on 20 mg/day. The incidence of rhabdomyolysis (defined as myopathy with a CK >40 times ULN) in patients on 80 mg/day was approximately 0.4% compared with 0% for patients on 20 mg/day. The incidence of myopathy, including rhabdomyolysis, was highest during the first year and then notably decreased during the subsequent years of treatment. In this trial, patients were carefully monitored and some interacting medicinal products were excluded.In a clinical trial in which 12,064 patients with a history of myocardial infarction were treated with simvastatin (mean follow-up 6.7 years), the incidence of myopathy (defined as unexplained muscle weakness or pain with a serum creatine kinase [CK] >10 times upper limit of normal [ULN]) in patients on 80 mg/day was approximately 0.9% compared with 0.02% for patients on 20 mg/day. The incidence of rhabdomyolysis (defined as myopathy with a CK >40 times ULN) in patients on 80 mg/day was approximately 0.4% compared with 0% for patients on 20 mg/day. The incidence of myopathy, including rhabdomyolysis, was highest during the first year and then notably decreased during the subsequent years of treatment. In this trial, patients were carefully monitored and some interacting medicinal products were excluded. The risk of myopathy, including rhabdomyolysis, is greater in patients on simvastatin 80 mg compared with other statin therapies with similar or greater LDL-C-lowering efficacy and compared with lower doses of simvastatin. Therefore, the 80-mg dose of simvastatin should be used only in patients who have been taking simvastatin 80 mg chronically (e.g., for 12 months or more) without evidence of muscle toxicity . If, however, a patient who is currently tolerating the 80-mg dose of simvastatin needs to be initiated on an interacting drug that is contraindicated or is associated with a dose cap for simvastatin, that patient should be switched to an alternative statin with less potential for the drug-drug interaction. Patients should be advised of the increased risk of myopathy, including rhabdomyolysis, and to report promptly any unexplained muscle pain, tenderness or weakness. If symptoms occur, treatment should be discontinued immediately . The risk of myopathy, including rhabdomyolysis, is greater in patients on simvastatin 80 mg compared with other statin therapies with similar or greater LDL-C-lowering efficacy and compared with lower doses of simvastatin. Therefore, the 80-mg dose of simvastatin should be used only in patients who have been taking simvastatin 80 mg chronically (e.g., for 12 months or more) without evidence of muscle toxicity [See Dosage and Administration, Restricted Dosing for 80 mg (2.2) ] . If, however, a patient who is currently tolerating the 80-mg dose of simvastatin needs to be initiated on an interacting drug that is contraindicated or is associated with a dose cap for simvastatin, that patient should be switched to an alternative statin with less potential for the drug-drug interaction. Patients should be advised of the increased risk of myopathy, including rhabdomyolysis, and to report promptly any unexplained muscle pain, tenderness or weakness. If symptoms occur, treatment should be discontinued immediately [See Warnings and Precautions (5.2) ] . There have been rare reports of immune-mediated necrotizing myopathy (IMNM), an autoimmune myopathy, associated with statin use. IMNM is characterized by: proximal muscle weakness and elevated serum creatine kinase, which persist despite discontinuation of statin treatment; muscle biopsy showing necrotizing myopathy without significant inflammation; improvement with immunosuppressive agents.There have been rare reports of immune-mediated necrotizing myopathy (IMNM), an autoimmune myopathy, associated with statin use. IMNM is characterized by: proximal muscle weakness and elevated serum creatine kinase, which persist despite discontinuation of statin treatment; muscle biopsy showing necrotizing myopathy without significant inflammation; improvement with immunosuppressive agents. In most cases, muscle symptoms and CK increases resolved when treatment was promptly discontinued. Periodic CK determinations may be considered in patients starting therapy with simvastatin or whose dose is being increased, but there is no assurance that such monitoring will prevent myopathy. All patients starting therapy with simvastatin, or whose dose of simvastatin is being increased, should be advised of the risk of myopathy, including rhabdomyolysis, and told to report promptly any unexplained muscle pain, tenderness or weakness particularly if accompanied by malaise or fever or if muscle signs and symptoms persist after discontinuing simvastatin. Simvastatin therapy should be discontinued immediately if myopathy is diagnosed or suspected. In most cases, muscle symptoms and CK increases resolved when treatment was promptly discontinued. Periodic CK determinations may be considered in patients starting therapy with simvastatin or whose dose is being increased, but there is no assurance that such monitoring will prevent myopathy. Many of the patients who have developed rhabdomyolysis on therapy with simvastatin have had complicated medical histories, including renal insufficiency usually as a consequence of long-standing diabetes mellitus. Such patients merit closer monitoring. Simvastatin therapy should be discontinued if markedly elevated CPK levels occur or myopathy is diagnosed or suspected. Simvastatin therapy should also be temporarily withheld in any patient experiencing an acute or serious condition predisposing to the development of renal failure secondary to rhabdomyolysis, e.g., sepsis; hypotension; major surgery; trauma; severe metabolic, endocrine, or electrolyte disorders; or uncontrolled epilepsy.Many of the patients who have developed rhabdomyolysis on therapy with simvastatin have had complicated medical histories, including renal insufficiency usually as a consequence of long-standing diabetes mellitus. Such patients merit closer monitoring. Simvastatin therapy should be discontinued if markedly elevated CPK levels occur or myopathy is diagnosed or suspected. Simvastatin therapy should also be temporarily withheld in any patient experiencing an acute or serious condition predisposing to the development of renal failure secondary to rhabdomyolysis, e.g., sepsis; hypotension; major surgery; trauma; severe metabolic, endocrine, or electrolyte disorders; or uncontrolled epilepsy.

Drug Interactions

The risk of myopathy and rhabdomyolysis is increased by elevated plasma levels of simvastatin and simvastatin acid. Simvastatin is metabolized by the cytochrome P450 isoform 3A4. Certain drugs which inhibit this metabolic pathway can raise the plasma levels of simvastatin and may increase the risk of myopathy. These include itraconazole, ketoconazole, posaconazole, voriconazole, the macrolide antibiotics erythromycin and clarithromycin, and the ketolide antibiotic telithromycin, HIV protease inhibitors, boceprevir, telaprevir, the antidepressant nefazodone, cobicistat-containing products, or grapefruit juice . Combination of these drugs with simvastatin is contraindicated. If short-term treatment with strong CYP3A4 inhibitors is unavoidable, therapy with simvastatin must be suspended during the course of treatment . The risk of myopathy and rhabdomyolysis is increased by elevated plasma levels of simvastatin and simvastatin acid. Simvastatin is metabolized by the cytochrome P450 isoform 3A4. Certain drugs which inhibit this metabolic pathway can raise the plasma levels of simvastatin and may increase the risk of myopathy. These include itraconazole, ketoconazole, posaconazole, voriconazole, the macrolide antibiotics erythromycin and clarithromycin, and the ketolide antibiotic telithromycin, HIV protease inhibitors, boceprevir, telaprevir, the antidepressant nefazodone, cobicistat-containing products, or grapefruit juice [See Clinical Pharmacology (12.3) ] . Combination of these drugs with simvastatin is contraindicated. If short-term treatment with strong CYP3A4 inhibitors is unavoidable, therapy with simvastatin must be suspended during the course of treatment [See Contraindications (4) and Drug Interactions (7.1) ] . The combined use of simvastatin with gemfibrozil, cyclosporine, or danazol is contraindicated . The combined use of simvastatin with gemfibrozil, cyclosporine, or danazol is contraindicated [See Contraindications (4) and Drug Interactions (7.1 and 7.2) ] . Caution should be used when prescribing other fibrates with simvastatin, as these agents can cause myopathy when given alone and the risk is increased when they are coadministered . Caution should be used when prescribing other fibrates with simvastatin, as these agents can cause myopathy when given alone and the risk is increased when they are coadministered [see Drug Interactions (7.2) ] . Cases of myopathy, including rhabdomyolysis, have been reported with simvastatin coadministered with colchicine, and caution should be exercised when prescribing simvastatin with colchicine . Cases of myopathy, including rhabdomyolysis, have been reported with simvastatin coadministered with colchicine, and caution should be exercised when prescribing simvastatin with colchicine [see Drug Interactions (7.7) ] . The benefits of the combined use of simvastatin with the following drugs should be carefully weighed against the potential risks of combinations: other lipid-lowering drugs (fibrates or, for patients with HoFH, lomitapide), amiodarone, dronedarone, verapamil, diltiazem, amlodipine, or ranolazine . The benefits of the combined use of simvastatin with the following drugs should be carefully weighed against the potential risks of combinations: other lipid-lowering drugs (fibrates or, for patients with HoFH, lomitapide), amiodarone, dronedarone, verapamil, diltiazem, amlodipine, or ranolazine [see Dosage and Administration (2.4) and Drug Interactions (7.3) ] . Cases of myopathy, including rhabdomyolysis, have been observed with simvastatin coadministered with lipid-modifying doses (≥1 g/day niacin) of niacin-containing products. [see Drug Interactions (7.4) ] . Prescribing recommendations for interacting agents are summarized in Table 1 . Prescribing recommendations for interacting agents are summarized in Table 1 [see also Dosage and Administration (2.3 , 2.4) , Drug Interactions (7) , Clinical Pharmacology (12.3) ] .

Table

1: Drug Interactions Associated with Increased Risk of Myopathy/Rhabdomyolysis Interacting Agents Prescribing Recommendations Strong CYP3A4 Inhibitors, e.g.:Strong CYP3A4 Inhibitors, e.g.: ItraconazoleItraconazole KetoconazoleKetoconazole PosaconazolePosaconazole VoriconazoleVoriconazole ErythromycinErythromycin ClarithromycinClarithromycin TelithromycinTelithromycin HIV protease inhibitorsHIV protease inhibitors BoceprevirBoceprevir TelaprevirTelaprevir NefazodoneNefazodone Cobicistat-containing productsCobicistat-containing products GemfibrozilGemfibrozil CyclosporineCyclosporine DanazolDanazol Contraindicated with simvastatin Niacin (≥1 g/day)Niacin (≥1 g/day)

For

Chinese patients, not recommended with simvastatin VerapamilVerapamil DiltiazemDiltiazem DronedaroneDronedarone Do not exceed 10 mg simvastatin daily AmiodaroneAmiodarone AmlodipineAmlodipine RanolazineRanolazine Do not exceed 20 mg simvastatin daily LomitapideLomitapide For patients with HoFH, do not exceed 20 mg simvastatin daily For patients with HoFH who have been taking 80 mg simvastatin chronically (e.g., for 12 months or more) without evidence of muscle toxicity, do not exceed 40 mg simvastatin when taking lomitapide. Grapefruit juiceGrapefruit juice Avoid grapefruit juice

5.2 Liver Dysfunction Persistent increases (to more than 3X the ULN) in serum transaminases have occurred in approximately 1% of patients who received simvastatin in clinical studies . When drug treatment was interrupted or discontinued in these patients, the transaminase levels usually fell slowly to pretreatment levels. The increases were not associated with jaundice or other clinical signs or symptoms. There was no evidence of hypersensitivity. In the Scandinavian Simvastatin Survival Study (4S) <span class="opacity-50 text-xs">[see Clinical Studies (14.1) ]</span> , the number of patients with more than one transaminase elevation to &gt; 3X ULN, over the course of the study, was not significantly different between the simvastatin and placebo groups (14 [0.7%] vs. 12 [0.6%]). Elevated transaminases resulted in the discontinuation of 8 patients from therapy in the simvastatin group (n=2,221) and 5 in the placebo group (n=2,223). Of the 1,986 simvastatin treated patients in 4S with normal liver function tests (LFTs) at baseline, 8 (0.4%) developed consecutive LFT elevations to &gt; 3X ULN and/or were discontinued due to transaminase elevations during the 5.4 years (median follow-up) of the study. Among these 8 patients, 5 initially developed these abnormalities within the first year. All of the patients in this study received a starting dose of 20 mg of simvastatin; 37% were titrated to 40 mg.

In

2 controlled clinical studies in 1,105 patients, the 12-month incidence of persistent hepatic transaminase elevation without regard to drug relationship was 0.9% and 2.1% at the 40- and 80-mg dose, respectively. No patients developed persistent liver function abnormalities following the initial 6 months of treatment at a given dose. It is recommended that liver function tests be performed before the initiation of treatment, and thereafter when clinically indicated. There have been rare postmarketing reports of fatal and non-fatal hepatic failure in patients taking statins, including simvastatin. If serious liver injury with clinical symptoms and/or hyperbilirubinemia or jaundice occurs during treatment with simvastatin, promptly interrupt therapy. If an alternate etiology is not found do not restart simvastatin. Note that ALT may emanate from muscle, therefore ALT rising with CK may indicate myopathy [see Warnings and Precautions (5.1) ] . The drug should be used with caution in patients who consume substantial quantities of alcohol and/or have a past history of liver disease. Active liver diseases or unexplained transaminase elevations are contraindications to the use of simvastatin. Moderate (less than 3X ULN) elevations of serum transaminases have been reported following therapy with simvastatin. These changes appeared soon after initiation of therapy with simvastatin, were often transient, were not accompanied by any symptoms and did not require interruption of treatment.

5.3 Endocrine Function Increases in HbA1c and fasting serum glucose levels have been reported with HMG-CoA reductase inhibitors, including simvastatin.