Consumer medicine information

Simvar Simvastatin Tablets

Simvastatin

BRAND INFORMATION

Brand name

Simvar

Active ingredient

Simvastatin

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using Simvar Simvastatin Tablets.

What is in this leaflet

This leaflet answers some common questions about simvastatin. It does not contain all the available information. It does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor has weighed the risks of you using this medicine against the benefits they expect it will have for you.

If you have any concerns about taking this medicine, ask your doctor or pharmacist.

Keep this leaflet with the medicine. You may want to read it again.

What this medicine is used for

Simvastatin is used:

  • to help lower cholesterol and triglyceride levels
  • in people who have coronary heart disease (CHD)
  • in people with a high risk of CHD (e.g. diabetes, a history of stroke, or other blood vessel disease)

Simvastatin can reduce the risk of a heart attack or stroke, reduce the need for surgery to increase blood flow to the heart and can reduce the need for hospitalisation due to angina.

Cholesterol:
Everyone has cholesterol and triglycerides in their blood. The body uses them for many things, such as building cell walls and hormones.

Your body makes cholesterol, but it also comes from food. The body balances the cholesterol it makes with the cholesterol it gets from food. This means if more cholesterol comes from food, less is made by the body. However, if you eat a high-fat diet, your body may not keep this balance and your cholesterol levels rise.

Too much cholesterol or triglycerides can be a problem. When you have high levels of cholesterol, it may 'stick' to the inside of your blood vessels instead of being carried to the parts of the body where it is needed. Over time this can form hard areas (called plaque) on the walls of blood vessels, making it more difficult for the blood to flow. This blocking of your blood vessels can lead to coronary heart disease (such as heart attacks and angina) and stroke. High cholesterol is more likely to occur with certain diseases or if you have a family history of high cholesterol.

There is usually no symptoms of high cholesterol or triglycerides. Your doctor can measure your cholesterol and triglycerides with a blood test.

There are two types of cholesterol, called LDL and HDL cholesterol. LDL cholesterol is the 'bad' cholesterol that can block vessels. HDL cholesterol is the 'good' cholesterol that is thought to remove bad cholesterol from blood vessels.

Triglycerides are an energy source for the body.

How it works

Simvastatin belongs to a group of medicines known as HMG-CoA reductase inhibitors.

Simvastatin works by reducing bad (LDL) cholesterol made by the liver and raises the good (HDL) cholesterol. It may slow the hardening of blood vessels and reduce the risk of developing new plaque.

Simvastatin does not reduce the cholesterol and triglycerides that come from fat in food. Therefore, you also need to follow a low-fat diet and other measures, such as exercise and weight control, while you are taking simvastatin.

Ask your doctor if you have any questions about why this medicine has been prescribed for you. Your doctor may have prescribed this medicine for another reason.

This medicine is available only with a doctor's prescription.

This medicine is not addictive.

Safety and effectiveness have been studied in 10-17 year old boys and in girls, who had started their menstrual period at least one year before (see How to take this medicine). This medicine has not been studied in children under the age of 10 years. For more information, talk to your doctor.

Before you take this medicine

When you must not take it

Do not take this medicine if you have an allergy to:

  • simvastatin
  • lactose
  • any of the ingredients listed at the end of this leaflet.

Some of the symptoms of an allergic reaction may include:

  • shortness of breath
  • wheezing or difficulty breathing
  • painful joints
  • swelling of the face, lips, tongue, throat or other parts of the body
  • rash, itching or hives on the skin

Do not take this medicine if you have or have had any of the following medical conditions:

  • liver disease or unexplained high levels of liver enzymes
  • muscle pain, tenderness or weakness (myopathy) from other medicines used to treat high cholesterol or triglycerides

Do not take this medicine if you are taking the following medicines:

  • gemfibrozil
  • ciclosporin
  • danazol
  • CYP3A4 inhibitors (e.g. itraconazole, ketoconazole, posaconazole, voriconazole)
  • HIV protease inhibitors (e.g. indinavir, nelfinavir, ritonavir, saquinavir)
  • hepatitis C virus protease inhibitors (e.g. boceprevir, telaprevir)
  • some antibiotics (e.g. fusidic acid, erythromycin, clarithromycin, telithromycin, daptomycin)
  • nefazodone

Do not take this medicine if you are pregnant or there is a chance that you could become pregnant (e.g. not using adequate contraception). Simvastatin may affect your developing baby if you take it during pregnancy.

Do not take this medicine if you are breastfeeding. Your baby may absorb this medicine from breast milk, and therefore there is a possibility of harm to the baby.

Do not take this medicine after the expiry date printed on the pack or if the packaging is torn or shows signs of tampering. If it has expired or is damaged, return it to your pharmacist for disposal.

If you are not sure whether you should start taking this medicine, talk to your doctor.

Before you start to take it

Tell your doctor if you have allergies to any other medicines, foods, preservatives or dyes.

Tell your doctor if you have or have had any of the following medical conditions:

  • liver disease
  • kidney disease
  • thyroid problems
  • unexplained muscle pain, tenderness or weakness not caused by exercise

Tell your doctor if you drink alcohol regularly.

Tell you doctor is become pregnant or plan to breast feed.

Tell you doctor if you are Asian.

Tell your doctor if you are taking niacin (also known as nicotinic acid) or a niacin-containing product, particularly if you are Chinese.

If you have not told your doctor about any of the above, tell them before you start taking this medicine.

Taking other medicines

Tell your doctor and pharmacist if you are taking any other medicines, including any that you get without a prescription from your pharmacy, supermarket or health food shop.

Some medicines must not be taken with simvastatin as they may increase the risk of muscle side effect with this medicine. It is particularly important to tell your doctor if you are taking:

  • nefazodone, used to treat depression
  • gemfibrozil, used to treat high cholesterol levels
  • ciclosporin, used to suppress the immune system
  • danazol
  • medicines known as 'CYP3A4 inhibitors', used to treat certain fungal infections (e.g. itraconazole, ketoconazole, posaconazole, voriconazole)
  • medicines containing cobicistat, used for HIV infection
  • HIV protease inhibitors (e.g. indinavir, nelfinavir, ritonavir, saquinavir)
  • certain hepatitis C virus protease inhibitors (e.g. boceprevir, telaprevir)
  • antibiotics used to treat infections (e.g. erythromycin, fusidic acid, clarithromycin, telithromycin, daptomycin)

If you are taking any of the above, your doctor may suggest stopping this medicine temporarily or permanently.

Some other medicines may interact with simvastatin. Because taking this medicine with any of the following drugs can increase the risk of muscle problems (see Side Effects), it is particularly important to tell your doctor if you are taking:

  • other medicines used to lower cholesterol levels, such as other fibrates, niacin (also known as nicotinic acid)
  • warfarin and other medicines used to prevent blood clots
  • colchicine, used for gout
  • medicines used to treat high blood pressure, angina or other heart conditions (e.g. verapamil, diltiazem, amlodipine)
  • lomitapide, used for a serious and rare genetic cholesterol condition
  • amiodarone, used to treat irregular heart beat
  • digoxin, used to treat heart failure
  • certain hepatitis C antiviral agents (e.g. elbasvir or grazoprevir)
  • daptomycin, a drug used to treat complicated skin and skin structure infections and bacteraemia.

These medicines may be affected by this medicine or may affect how well it works, or may increase the risk of side effects with this medicine. You may need different amounts of your medicines, or you may need to take different medicines.

Your doctor and pharmacist have more information on medicines to be careful with or avoid while taking this medicine.

You should also tell any doctor who is prescribing a new medication for you that you are taking this medicine.

Grapefruit juice, especially in large amounts, may also interfere with the way simvastatin works in your body. However, one glass of grapefruit juice per day is unlikely to have any effect.

How to take this medicine

Follow all directions given to you by your doctor or pharmacist carefully. They may differ to the information contained in this leaflet.

If you do not understand the instructions on the pack, ask your doctor or pharmacist for help.

How much to take

Take this medicine only when prescribed by your doctor.

Your doctor will tell you how much of this medicine you should take, depending on your condition and whether you are taking other medicines.

For adults, the recommended starting dose is 10 mg or 20 mg per day, taken in the evening, which may need to be increased up to 80 mg daily to have the best effect

Because of the increased risk of muscle problems, the 80 mg dose should only be used in patients at a high risk of heart problems who have not reached their cholesterol goal on lower doses.

For children (10-17 years old), the maximum recommended dose is 40 mg a day.

For people with CHD or risk of CHD:

The usual starting dose is 40 mg per day, taken in the evening.

How to take it

Swallow the tablets whole with a glass of water.

When to take it

Take this medicine at the same time each day, preferably in the evening. The liver produces its greatest amount of cholesterol when the body is at rest and when there is no dietary intake. For most people, this is at night when asleep. Therefore, this medicine is more effective when taken in the evening, such as after your evening meal, however it can be taken without food.

Taking it at the same time each day will have the best effect and will also help you remember when to take it.

How long to take it for

Continue taking this medicine for as long as your doctor tells you.

Simvastatin helps to lower your cholesterol, but it does not cure your condition. It is important to keep taking your medicine even if you feel well. You may have to take cholesterol-lowering medicines for the rest of your life. If you stop taking this medicine, your cholesterol levels may rise again.

Make sure you have enough to last over weekends and holidays.

If you forget to take it

If it is almost time to take your next dose, skip the dose you missed and take your next dose at the usual time.

Otherwise take it as soon as you remember and then go back to taking your medicine as you would normally.

If you are not sure whether to skip the dose, talk to your doctor or pharmacist.

Do not take a double dose to make up for missed doses. This may increase the chance of you experiencing side effects.

If you have trouble remembering to take your medicine, ask your pharmacist for some hints.

If you take too much (overdose)

Immediately telephone your doctor or the Poisons Information Centre (telephone 13 11 26) for advice, or go to Accident and Emergency at your nearest hospital if you think that you or anyone else may have taken too much of this medicine. Do this even if there are no signs of discomfort or poisoning. You may need urgent medical attention.

While you are taking this medicine

Things you must do

If you are about to be started on any new medicine, remind your doctor and pharmacist that you are taking this medicine.

Tell any other doctors, dentists and pharmacists who are treating you that you take this medicine.

If you become pregnant while taking this medicine, stop taking it and tell your doctor immediately.

Keep all of your doctor's appointments so that your progress can be checked. Your doctor may occasionally do tests to make sure the medicine is working and to prevent side effects.

Your doctor may suggest stopping the tablets a few days before surgery.

Things you must not do

Do not give this medicine to anyone else, even if they have the same condition as you.

Do not take your medicine to treat any other complaint unless your doctor tells you to.

Do not stop taking your medicine or change the dosage without first checking with your doctor.

Things to be careful of

Be careful driving or operating machinery until you know how this medicine affects you. Simvastatin generally does not affect your ability to drive a car or operate machinery. However, this medicine may cause dizziness in some people. Make sure you know how you react to this medicine before you drive a car or operate machinery.

Avoid drinking alcohol. Drinking large amounts of alcohol may increase the risk of liver problems.

Avoid drinking large quantities of grapefruit juice. Grapefruit juice can alter the metabolism of simvastatin.

Changes to lifestyle that may help reduce the chance of coronary heart disease

Lowering high cholesterol can help reduce your chances of having coronary heart disease (CHD). However, your chances of having CHD may be increased by several other factors including high blood pressure, cigarette smoking, diabetes, excess weight, family history of CHD, being a male and being a woman who has reached menopause.

Some self help measures suggested below may help your condition and help reduce your chances of having CHD. Talk to your doctor, pharmacist, or dietician about these measures and for more information.

  • Diet
    - continue the low fat diet recommended by your doctor, dietician or pharmacist.
  • Weight
    - your doctor may advise you to lose weight if you are overweight.
  • Exercise
    - make exercise a part of your routine – walking is good. Ask your doctor for advise before starting exercise.
  • Smoking
    - your doctor may advise you to stop smoking or at least cut down.

Side effects

Tell your doctor and pharmacist as soon as possible if you do not feel well while you are taking simvastatin.

This medicine helps most people, but may cause unwanted side effects in some people. All medicines can have side effects. Sometimes they are serious, most of the time they are not. You may need medical attention if you get some of the side effects.

Do not be alarmed by the following lists of side effects. You may not experience any of them.

Ask your doctor or pharmacist to answer any questions you may have.

Tell your doctor if you notice any of the following:

  • stomach upset, such as nausea, vomiting, constipation, diarrhoea, flatulence, pain, reflux
  • headache
  • dizziness

The above list includes the more common side effects of your medicine. For the most part, these have been mild and short-lived.

Tell your doctor as soon as possible if you notice any of the following:

  • tingling or numbness in the hands or feet
  • tiredness, shortness of breath, looking pale (signs of anaemia)
  • fever, flushing and/or generally feeling unwell
  • skin rash, itchiness
  • pinkish, itchy swellings on the skin, also called hives or nettle rash
  • painful, swollen joints
  • bruising more easily than normal
  • larger breasts than normal in men

The above list includes serious side effects that may require medical attention.

Liver problems can also occur and may be serious. Your doctor will do blood test to check your liver.

If any of the following happen, tell your doctor immediately or go to Accident and Emergency at your nearest hospital:

  • shortness of breath, wheezing or difficulty breathing; swelling of the face, lips, tongue, or other parts of the body; rash, itching or hives on the skin (signs of an allergic reaction)
  • dry cough, trouble breathing, high temperature, weight loss, feeling tired (signs of interstitial lung disease)
  • feeling unusually tired or weak; loss of appetite; yellowing of the skin and/or eyes, also called jaundice; dark urine (signs of a liver problem)
  • sharp pain in the upper stomach (pancreatitis)
  • brown or dark coloured urine, severe muscle aching all through the body, muscle weakness (muscle breakdown)

Rarely, muscle breakdown can be serious and result in kidney damage or lead to death. The risk of muscle problems is greater for:

  • patients taking higher doses of simvastatin, such as 80 mg
  • older patients (65 years of age and older)
  • female patients
  • patients with abnormal kidney function
  • patients with thyroid problems.

Tell your doctor if you notice:

  • hair loss
  • muscle cramps
  • trouble sleeping
  • poor memory, memory loss, confusion
  • feelings of depression
  • blurred vision and impaired vision
  • erectile dysfunction
  • breathing problems including persistent cough and/or shortness of breath or fever
  • gynaecomastia (breast enlargement in men) (very rare)
  • muscle rupture (very rare)
  • rash that occur on the skin or sores in the mouth (lichenoid drug eruptions) (very rare)

These are other side effects that have been reported with simvastatin.

Tell your doctor or pharmacist if you notice anything that is making you feel unwell.

Other side effects not listed above may occur in some patients.

Storage and disposal

Storage

Keep your medicine in its pack until it is time to take it. If you take your medicine out of its pack it may not keep well.

Keep your medicine in a cool dry place where the temperature stays below 25°C. Protect from light and moisture.

Do not store your medicine or any other medicine in the bathroom or near a sink. Do not leave it on a window sill or in the car. Heat and dampness can destroy some medicines.

Keep this medicine where children cannot reach it. A locked cupboard at least one-and-a-half metres above the ground is a good place to store medicines.

Disposal

If your doctor tells you to stop taking this medicine or the expiry date has passed, ask your pharmacist what to do with any medicine leftover.

Product description

What it looks like

10 mg Tablets
Light pink coloured, oval, biconvex film-coated tablets, marked 'SVN 10' on one side and 'NEO' on the other side.

Blister packs of 30 tablets:. AUST R 211952

20 mg Tablets
Tan coloured, oval, biconvex film-coated tablets, marked with 'SVN 20' on one side and 'NEO' on the other side.

Blister packs of 30 tablets: AUST R 211953.

40 mg Tablets
Pink coloured, oval, biconvex film-coated tablets, marked 'SVN 40' on one side and 'NEO' on the other side.

Blister packs of 30 tablets: AUST R 211954

80 mg Tablets
Pink coloured, capsule-shaped, biconvex film-coated tablets marked with 'SVN 80' on one side and 'NEO' on the other side.

Blister packs of 30 tablets:. AUST R 211955

*Not all strengths, pack types and/or pack sizes may be available.

Ingredients

Each tablet contains either 10, 20, 40 or 80 mg of simvastatin as the active ingredient.

It also contains the following:

  • butylated hydroxyanisole
  • ascorbic acid
  • citric acid monohydrate
  • microcrystalline cellulose
  • magnesium stearate
  • lactose monohydrate
  • pregelatinised maize starch
  • Opadry 20A54692 Pink (10 mg only)
  • Opadry 20A56767 Brown (20 mg only)
  • Opadry 20A54535 Pink (40 mg and 80 mg only)

Contains sugars as lactose

This medicine does not contain gluten, sucrose, tartrazine or any other azo dyes.

Sponsor

Apotex Pty Ltd
16 Giffnock Avenue
Macquarie Park NSW 2113

This leaflet was prepared in November 2021.

Published by MIMS January 2022

BRAND INFORMATION

Brand name

Simvar

Active ingredient

Simvastatin

Schedule

S4

 

1 Name of Medicine

Simvastatin.

2 Qualitative and Quantitative Composition

Simvastatin is a lipid-lowering agent derived synthetically from a fermentation product of Aspergillus terreus.
Simvastatin is a white crystalline powder, practically insoluble in water and freely soluble in chloroform, methanol and ethanol.
Each tablet contains simvastatin 10 mg, 20 mg, 40 mg or 80 mg.

Excipients with known effect.

Sugars as lactose.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

10 mg tablet.

Light pink coloured, oval, biconvex film-coated tablets, marked "SVN 10" on one and 'NEO' on the other side.

20 mg tablet.

Tan coloured, oval, biconvex film-coated tablets, marked with "SVN 20" on one side and 'NEO' on the other side.

40 mg tablet.

Pink coloured, oval, biconvex film coated tablets, marked "SVN 40" on one side 'NEO' on the other side.

80 mg tablet.

Pink coloured, capsule-shaped, biconvex film-coated tablets marked with "SVN 80" on one side and 'NEO' on the other side.

4 Clinical Particulars

4.1 Therapeutic Indications

Simvastatin is indicated as an adjunct to diet for treatment of hypercholesterolaemia.
Prior to initiating therapy with simvastatin, secondary causes of hypercholesterolaemia (e.g. poorly controlled diabetes mellitus, hypothyroidism, nephrotic syndrome, dysproteinaemias, obstructive liver disease, other drug therapy, alcoholism) should be identified and treated.
Simvastatin is indicated in patients at high risk of CHD (with or without hypercholesterolaemia) including patients with diabetes, history of stroke or other cerebrovascular disease, peripheral vessel disease, or with existing CHD to reduce the risk of cardiovascular death, major cardiovascular events including stroke, and hospitalisation due to angina pectoris.
These effects do not replace the need to independently control known causes of cardiovascular mortality and morbidity such as hypertension, diabetes and smoking.

4.2 Dose and Method of Administration

The dosage range for simvastatin is 10-80 mg/day, given as a single dose in the evening. Adjustments of dosage, if required, should be made at intervals of not less than 4 weeks, to a maximum of 80 mg/day given as a single dose in the evening. The 80 mg dose of simvastatin should only be used in patients at high risk for cardiovascular complications who have not achieved their treatment goals on lower doses and when the benefits are expected to outweigh the potential risks (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Patients at high risk of coronary heart disease (CHD) or with existing CHD.

The usual starting dose of simvastatin is 40 mg/day given as a single dose in the evening in patients at high risk of CHD (with or without hypercholesterolaemia), i.e. patients with diabetes, history of stroke or other cerebrovascular disease, peripheral vessel disease, or with existing CHD. Drug therapy can be initiated simultaneously with diet and exercise.

Hypercholesterolaemia and combined hyperlipidaemia (patients who are not in the risk categories above).

The patient should be placed on a standard cholesterol lowering diet before receiving simvastatin and should continue on this diet during treatment with simvastatin.
The recommended starting dose is 10 to 20 mg per day in the evening. Therapy should be individualised according to the patient's response.

Concomitant therapy.

Simvastatin is effective alone or in combination with bile acid sequestrants.
In patients taking fibrates other than gemfibrozil or fenofibrate (see Section 4.3 Contraindications) concomitantly with simvastatin, the dose of simvastatin should not exceed 10 mg/day.
In patients taking amiodarone, verapamil or diltiazem concomitantly with simvastatin, the dose of simvastatin should not exceed 20 mg/day.
Patients taking more than 20 mg daily of simvastatin should not be treated with products containing elbasvir or grazoprevir at the same time.
In patients taking amlodipine concomitantly with simvastatin, the dose of simvastatin should not exceed 40 mg/day (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
In patients taking niacin (nicotinic acid) ≥ 1 g/day, the dose of simvastatin should not exceed 40 mg/day (see Section 4.4 Special Warnings and Precautions for Use).
In patients taking lomitapide concomitantly with simvastatin, the dose of simvastatin should not exceed 40 mg/day (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

Dosage in renal insufficiency.

Simvastatin does not undergo significant renal excretion.
However, because no data is available in patients with impaired renal function, caution should be used in these patients.
In patients with severe renal insufficiency (creatinine clearance < 30 mL/min), dosages above 10 mg/day should be carefully considered and, if deemed necessary, implemented cautiously.

4.3 Contraindications

Hypersensitivity to any component of this preparation.
Active liver disease or unexplained persistent elevations of serum transaminases.
Pregnancy and nursing (see Section 4.4 Special Warnings and Precautions for Use). Women of childbearing potential, unless on an effective contraceptive and highly unlikely to conceive.
Myopathy secondary to other lipid lowering agents.
Concomitant administration of potent CYP3A4 inhibitors (e.g. itraconazole, ketoconazole, posaconazole, voriconazole, HIV protease inhibitors, boceprevir, telaprevir, erythromycin, clarithromycin, telithromycin, nefazodone, and drugs containing cobicistat) (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Concomitant administration of gemfibrozil, ciclosporin, or danazol (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Concomitant use with fusidic acid (see Section 4.4 Special Warnings and Precautions for Use; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

4.4 Special Warnings and Precautions for Use

Myopathy/rhabdomyolysis.

Simvastatin, like other inhibitors of HMG-CoA reductase, occasionally causes myopathy manifested as muscle pain, tenderness or weakness with creatine kinase (CK) above 10 x 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 high levels of HMG-CoA reductase inhibitory activity in plasma (i.e. elevated simvastatin and simvastatin acid plasma levels), which may be due, in part, to interacting drugs that interfere with simvastatin metabolism and/or transporter pathways (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions). Predisposing factors for myopathy include advanced age (≥ 65 years), female gender, uncontrolled hypothyroidism, and renal impairment.
In 4S, there was one case of myopathy among 1,399 patients taking simvastatin 20 mg/day and no cases among 822 patients taking 40 mg/day for a median duration of 5.4 years. In two 6 month controlled clinical studies, there was one case of myopathy among 436 patients taking 40 mg and 5 cases among 669 patients taking 80 mg.
As with other HMG-CoA reductase inhibitors, the risk of myopathy/rhabdomyolysis is dose related for simvastatin. 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%, 0.08% and 0.61% at 20, 40 and 80 mg/day, respectively. In these trials, patients were carefully monitored and some interacting medicinal products were excluded.
In a major, large, long-term clinical trial (SEARCH) in which patients with a history of myocardial infarction were treated with simvastatin 80 mg/day (mean follow up 6.7 years), the incidence of myopathy was approximately 1.0% compared with 0.02% for patients on 20 mg/day. This includes rhabdomyolysis for which the incidence was 0.1 to 0.2%, all allocated to simvastatin 80 mg/day. There is no universally accepted definition of rhabdomyolysis. In SEARCH, rhabdomyolysis was defined as a subset of myopathy with CK > 40 x ULN plus evidence of end organ damage (e.g. elevated creatinine, dark urine). Approximately half of all the myopathy cases occurred during the first year of treatment. The incidence of myopathy during each subsequent year of treatment was approximately 0.1%.
The risk of myopathy is greater in patients on simvastatin 80 mg compared with other statin base therapies with similar LDL-C lowering efficacy. Therefore, the 80 mg dose of simvastatin should only be used in patients at high risk for cardiovascular complications who have not achieved their treatment goals on lower doses and when the benefits are expected to outweigh the potential risks. In patients taking simvastatin 80 mg for whom an interacting agent is needed, a lower dose of simvastatin or an alternative statin based regimen with less potential for drug-drug interactions should be used (see Section 4.3 Contraindications; Section 4.2 Dose and Method of Administration).
All patients starting therapy with simvastatin, or whose dose of simvastatin is being increased, should be advised of the risk of myopathy and told to report promptly any unexplained muscle pain, tenderness or weakness. Simvastatin therapy should be discontinued immediately if myopathy is diagnosed or suspected. The presence of these symptoms and a CK level > 10 times the upper limit of normal indicates myopathy. In most cases, when patients were promptly discontinued from treatment, muscle symptoms and CK increases resolved (see Section 4.8 Adverse Effects (Undesirable Effects)). Periodic CK determinations may be considered in patients starting therapy with simvastatin or whose dose is being increased.
Periodic CK determinations are recommended for patients titrating to the 80 mg dose. 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. Therapy with simvastatin should be temporarily stopped a few days prior to elective major surgery and when any major medical or surgical condition supervenes.
An increased risk of myopathy in Chinese subjects has been identified. In a clinical trial in which patients at high risk of cardiovascular disease were treated with simvastatin 40 mg/day (median follow-up 3.9 years), the incidence of myopathy was approximately 0.05% for non-Chinese patients (n=4 of 7367) compared with 0.24% for Chinese patients (n=13 of 5468). While the only Asian population assessed in this clinical trial was Chinese, caution should be used when prescribing simvastatin to Asian patients and the lowest dose necessary should be employed.
The risk of myopathy/rhabdomyolysis is increased by concomitant use of simvastatin with the following:

Contraindicated medicines.

Potent inhibitors of CYP3A4.

Concomitant use with medicines labelled as having a potent inhibitory effect on CYP3A4 at therapeutic doses (e.g. itraconazole, ketoconazole, posaconazole, voriconazole, erythromycin, clarithromycin, telithromycin, HIV protease inhibitors, boceprevir, telaprevir, nefazodone, or drugs containing cobicistat) is contraindicated. The risk of myopathy is increased by high levels of HMG-CoA reductase inhibitory activity in plasma. Potent inhibitors of CYP3A4 can raise the plasma levels of HMG-CoA reductase inhibitory activity and increase the risk of myopathy. If short-term treatment with potent CYP3A4 inhibitors is unavoidable, therapy with simvastatin should be suspended during the course of treatment (see Section 4.3 Contraindications; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

Gemfibrozil, ciclosporin or danazol.

Concomitant use of these drugs with simvastatin is contraindicated (see Section 4.3 Contraindications).

Fusidic acid.

Patients on fusidic acid treated concomitantly with simvastatin may have an increased risk of myopathy/rhabdomyolysis (see Section 4.3 Contraindications; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions). Fusidic acid must not be coadministered with statins (see Section 4.3 Contraindications). In patients where the use of systemic fusidic acid is considered essential, simvastatin should be discontinued throughout the duration of fusidic acid treatment. The patient should be advised to seek medical advice immediately if they experience any symptoms of muscle weakness, pain or tenderness.
Simvastatin therapy may be reintroduced seven days after the last dose of fusidic acid.

Other medicines.

Amiodarone. In a clinical trial, myopathy was reported in 6% of patients receiving simvastatin 80 mg and amiodarone. In the same clinical trial, there were no cases of myopathy reported in patients receiving simvastatin 20 mg and amiodarone (see Table 1). The dose of simvastatin should not exceed 20 mg daily in patients receiving concomitant medication with amiodarone (see Section 4.2 Dose and Method of Administration; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Calcium channel blockers.

Verapamil and diltiazem.

The dose of simvastatin should not exceed 20 mg daily in patients receiving concomitant medication with verapamil or diltiazem (see Table 1; see Section 4.2 Dose and Method of Administration; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

Amlodipine.

In a clinical trial, patients on amlodipine treated concomitantly with simvastatin 80 mg had a slightly increased risk of myopathy. The dose of simvastatin should not exceed 40 mg daily in patients receiving concomitant medication with amlodipine (see Table 1; see Section 4.2 Dose and Method of Administration; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Lomitapide. The dose of simvastatin should not exceed 40 mg daily in patients with homozygous familial hypercholesterolemia (HoFH) receiving concomitant medication with lomitapide (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Moderate inhibitors of CYP3A4. Patients taking other medicines labelled as having a moderate inhibitor effect on CYP3A4 concomitantly with simvastatin, particularly higher simvastatin doses, may have an increased risk of myopathy. When co-administering simvastatin with a moderate inhibitor of CYP3A4, a dose adjustment of simvastatin may be necessary.
Other fibrates. The dose of simvastatin should not exceed 10 mg daily in patients receiving concomitant medication with other fibrates (except fenofibrate). When simvastatin and fenofibrate are given concomitantly, there is no evidence that the risk of myopathy exceeds the sum of the individual risks of each agent. Caution should be used when prescribing fenofibrate with simvastatin, as either agent can cause myopathy when given alone. Addition of fibrates to simvastatin typically provides little additional reduction in LDL-C, but further reductions of TG and further increases in HDL-C may be obtained. Combinations of fibrates with simvastatin have been used without myopathy in small, short-term clinical studies with careful monitoring.
Inhibitors of breast cancer resistance protein (BCRP). Concomitant administration of products that are inhibitors of BCRP (e.g. elbasvir and grazoprevir) may lead to increased plasma concentrations of simvastatin and an increased risk of myopathy; therefore, a dose adjustment of simvastatin may be necessary. Coadministration of elbasvir and grazoprevir with simvastatin has not been studied; however, the dose of simvastatin should not exceed 20 mg daily in patients receiving concomitant medication with products containing elbasvir or grazoprevir (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).
Niacin (≥ 1 g/day). The dose of simvastatin should not exceed 40 mg daily in patients receiving concomitant medication with niacin (nicotinic acid) ≥ 1 g/day. Cases of myopathy/rhabdomyolysis have been observed with simvastatin co-administered with lipid modifying doses (≥ 1 g/day) of niacin. In a clinical trial (median follow-up 3.9 years) involving patients at high risk of cardiovascular disease and with well-controlled LDL-C levels on simvastatin 40 mg/day with or without ezetimibe 10 mg, there was no incremental benefit on cardiovascular outcomes with the addition of lipid modifying doses (≥ 1 g/day) of niacin. Therefore, the benefit of the combined use of simvastatin with niacin should be carefully weighed against the potential risks of the combination. In addition, in this trial, the incidence of myopathy was approximately 0.24% for Chinese patients on simvastatin 40 mg or ezetimibe/simvastatin 10/40 mg compared with 1.24% for Chinese patients on simvastatin 40 mg or ezetimibe/simvastatin 10/40 mg co-administered with extended-release niacin/laropiprant 2 g/40 mg. In comparison, in European/Non-Chinese patients the incidence of myopathy was approximately 0.05% for patients on simvastatin 40 mg or ezetimibe/simvastatin 10/40 mg compared with 0.09% for patients on simvastatin 40 mg or ezetimibe/simvastatin 10/40 mg co-administered with extended-release niacin/laropiprant 2 g/40 mg. While the only Asian population assessed in this clinical trial was Chinese, because the incidence of myopathy is higher in Chinese than in European/Non-Chinese patients, co-administration of simvastatin with lipid-modifying doses (≥ 1 g/day) of niacin is not recommended in Asian patients.
Prescribing recommendations for interacting agents are summarised in Table 1 (further details are provided in the text) (also see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions; Section 5 Pharmacological Properties).
Daptomycin. Reports of myopathy and/or rhabdomyolysis have been observed with HMG-CoA reductase inhibitors coadministered with daptomycin. Caution should be used when prescribing HMG-CoA reductase inhibitors with daptomycin, as either agent can cause myopathy and/or rhabdomyolysis when given alone. Consideration should be given to suspending Simvar temporarily in patients taking daptomycin (see Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

Use in hepatic impairment.

In clinical studies, persistent increases (to more than 3 x ULN) in serum transaminases have occurred in 1% of adult patients who received simvastatin. When the drug was interrupted or discontinued in these patients, transaminases usually fell slowly to pre-treatment concentration. The increases were not associated with jaundice or other clinical signs or symptoms. There was no evidence of hypersensitivity. Some of these patients had abnormal liver function tests (LFTs) prior to therapy with simvastatin and/or consumed substantial quantities of alcohol.
In 4S (see Section 5.1 Pharmacodynamic Properties, Clinical trials), the number of patients with more than one ALT elevation to > 3 x ULN, over the course of the study, was not significantly different between the simvastatin and placebo groups (14 (0.7%) vs 12 (0.6%)). The incidence of ALT elevations in simvastatin subjects was greater than the incidence of AST elevations, and the number of subjects with at least one elevation of ALT greater than 3 x ULN was 46 (2.2%) in the simvastatin group and 32 (1.4%) in the placebo group, the difference not being statistically significant. The frequency of single elevations of ALT to 3 x ULN was significantly higher in the simvastatin group in the first year of the study (20 vs. 8, p=0.023), but not thereafter. 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 1986 simvastatin treated patients in 4S with normal LFTs at baseline, only 8 (0.4%) developed consecutive LFT elevations to > 3 x ULN and/or were discontinued due to transaminase elevations during the 5.4 years (median follow-up) of the study. All of the patients in this study received a starting dose of 20 mg of simvastatin; 37% were titrated to 40 mg.
In two controlled clinical studies in 1,105 patients, the 6 month incidence of persistent hepatic transaminase elevations considered drug related was 0.7% and 1.8% at the 40 and 80 mg dose, respectively.
In HPS (see Section 5.1 Pharmacodynamic Properties, Clinical trials), in which 20,536 patients were randomised to receive simvastatin 40 mg/day or placebo, the incidences of elevated transaminases (> 3 x ULN confirmed by repeat test) were 0.21% (n=21) for patients treated with simvastatin and 0.09% (n=9) for patients treated with placebo.
Liver function tests should be performed before the initiation of treatment and thereafter when clinically indicated. Patients titrated to the 80 mg dose should receive an additional test at 3 months. Note that ALT may emanate from muscle, therefore ALT rising with CK may indicate myopathy (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).
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 hyperbilirubinaemia or jaundice occurs during treatment with simvastatin, promptly interrupt therapy. If an alternate aetiology is not found do not restart simvastatin.
Patients who develop increased transaminase levels should have the finding confirmed and be followed thereafter with frequent liver tests until the abnormality(ies) return to normal. Should an increase in AST or ALT of 3 x ULN persist, withdrawal of simvastatin therapy is recommended. Liver biopsy should be considered if elevations persist despite discontinuation of the drug. Unconfirmed reports of "drug-induced hepatitis" have been reported with simvastatin.
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.
As with other lipid-lowering agents, moderate (less than 3 x ULN) elevations of serum transaminases have been reported following therapy with simvastatin. These changes were not specific to simvastatin and were also observed with comparative lipid lowering agents. They generally appeared within the first 3 months after initiation of therapy with simvastatin, were often transient, were not accompanied by any symptoms, and interruption of treatment was not required.

Immune mediated necrotising myopathy.

There have been rare reports of an immune-mediated necrotising myopathy (IMNM) during or after treatment with some statins. IMNM is clinically characterised by persistent proximal muscle weakness and elevated serum creatinine kinase, which persists despite discontinuation of statin treatment.

Interstitial lung disease.

Cases of interstitial lung disease have been reported with some statins, including simvastatin especially with long-term therapy (see Section 4.8 Adverse Effects (Undesirable Effects)). Presenting features can include dyspnoea, non-productive cough and deterioration in general health (fatigue, weight loss and fever). If it is suspected a patient has developed interstitial lung disease, statin therapy should be discontinued.

Ophthalmic evaluations.

Current long-term data from clinical studies, e.g. 4S, do not indicate an adverse effect of simvastatin on the human lens. However, the very long-term effects are not yet established and therefore periodic ophthalmic examinations are recommended after five years of treatment, taking into consideration that in the absence of any drug therapy, an increase in the prevalence of lens opacities with time is expected as a result of aging.

Animal studies.

Cataracts have been detected in two-year studies in rats and dogs at dose levels greater than 25 and 10 mg/kg/day, respectively, although at a very low incidence. While there is no clear correlation between the magnitude of serum lipid lowering and the development of cataracts, a consistent relationship has been observed between high serum levels of drug and cataract development with simvastatin and related HMG-CoA reductase inhibitors.
Serum levels (expressed as total inhibitors) in rats at the no effect dose level were 3-11 times higher than those in humans receiving the maximum daily dose of 80 mg, whereas serum levels at the no effect level in dogs were approximately two-fold higher than those in humans receiving the maximum daily dose of 80 mg.

Thyroid function.

The concentration of serum thyroxine has been measured at baseline and at the end of simvastatin treatment in 785 patients enrolled in multicentre studies. The results of this analysis indicate that simvastatin has little, if any, effect upon thyroxine activity.
In one study involving 183 patients treated with simvastatin, four patients had TSH levels within the normal range before commencing simvastatin but had an elevated TSH after two years of simvastatin therapy.

Transient hypotension.

Three cases of symptomatic hypotension in the first few days following the start of simvastatin therapy have been reported. Two of the patients were on antihypertensive medication. The hypotension resolved with continued therapy with simvastatin.

Neurological effects.

The neurological adverse effects reported to date include cases of peripheral neuropathy and paraesthesia possibly due to simvastatin.

Use in the elderly.

In controlled clinical trials, the efficacy of simvastatin for patients over the age of 65 years, as assessed by reduction in total-C and LDL-C levels, was similar to that seen in the population as a whole. There was no apparent increase in the overall frequency of clinical or laboratory adverse findings.
However, in a clinical trial of patients treated with simvastatin 80 mg/day, patients ≥ 65 years of age had an increased risk of myopathy compared to patients < 65 years of age.

Paediatric use.

Safety and effectiveness of simvastatin in patients 10-17 years of age with heterozygous familial hypercholesterolaemia have been evaluated in a controlled clinical trial in adolescent boys and in girls who were at least one year post-menarche. Patients treated with simvastatin had an adverse experience profile generally similar to that of patients treated with placebo. Doses greater than 40 mg have not been studied in this population. In this limited controlled study, there was no detectable effect on growth or sexual maturation in the adolescent boys or girls, or any effect on menstrual cycle length in girls (see Section 4.8 Adverse Effects (Undesirable Effects)). Adolescent females should be counselled on appropriate contraceptive methods while on simvastatin therapy (see Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use; Section 4.6 Fertility, Pregnancy and Lactation, Use in pregnancy (Category D)). Simvastatin has not been studied in patients younger than 10 years of age, nor in pre-menarchal girls.
The safety and efficacy of doses above 40 mg daily have not been studied in children with heterozygous familial hypercholesterolaemia. The long-term efficacy of simvastatin therapy in childhood to reduce morbidity and mortality in adulthood has not been established.
The safety and efficacy of simvastatin in children and adolescents with non-familial hypercholesterolaemia, those aged less than 10 years or pre-menarchal girls have not been studied.

Effects on laboratory tests.

See Section 4.8 Adverse Effects (Undesirable Effects).

4.5 Interactions with Other Medicines and Other Forms of Interactions

Multiple mechanisms may contribute to potential interactions with HMG-CoA reductase inhibitors. Drugs or herbal products that inhibit certain enzymes (e.g. CYP3A4) and/or transporter (e.g. OATP1B) pathways may increase simvastatin and simvastatin acid plasma concentrations and may lead to an increased risk of myopathy/rhabdomyolysis.
Consult the prescribing information of all concomitantly used drugs to obtain further information about their potential interactions with simvastatin and/or the potential for enzyme or transporter alterations and possible adjustments to dose and regimens.

CYP3A4 interactions.

Simvastatin is metabolised by CYP3A4 but has no CYP3A4 inhibitory activity; therefore it is not expected to affect the plasma concentrations of other drugs metabolized by CYP3A4.

Contraindicated medicines.

Concomitant use of the following medicines is contraindicated.

Potent CYP3A4 inhibitors.

Potent inhibitors of CYP3A4 (below) increase the risk of myopathy by reducing the elimination of simvastatin. Concomitant use with medicines labelled as having a potent inhibitory effect on CYP3A4 (e.g. itraconazole, ketoconazole, posaconazole, voriconazole, erythromycin, clarithromycin, telithromycin, HIV protease inhibitors, boceprevir, telaprevir, nefazodone, drugs containing cobicistat) is contraindicated (see Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 5.2 Pharmacokinetic Properties).

Gemfibrozil, ciclosporin or danazol.

(See Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis.)

Fusidic acid.

The risk of myopathy including rhabdomyolysis may be increased by the concomitant administration of simvastatin with fusidic acid. Co-administration of this combination may cause increased plasma concentrations of both agents. The mechanism of this interaction (whether it is pharmacodynamics or pharmacokinetic, or both) is yet unknown. There have been reports of rhabdomyolysis (including some fatalities) in patients receiving fusidic acid and statins. Where the use of fusidic acid is considered essential, simvastatin should be discontinued throughout the duration of fusidic acid treatment (see Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Other drug interactions.

Amiodarone.

The risk of myopathy/rhabdomyolysis is increased by concomitant administration of amiodarone with simvastatin (see Section 4.2 Dose and Method of Administration; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Calcium channel blockers.

The risk of myopathy/rhabdomyolysis is increased by concomitant administration of verapamil, diltiazem, or amlodipine (see Section 4.2 Dose and Method of Administration; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Lomitapide.

The risk of myopathy/rhabdomyolysis may be increased by concomitant administration of lomitapide (see Section 4.2 Dose and Method of Administration; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Moderate inhibitors of CYP3A4.

Patients taking other medicines labeled as having a moderate inhibitory effect on CYP3A4 concomitantly with simvastatin, particularly higher simvastatin doses, may have an increased risk of myopathy (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Inhibitors of the transport protein OATP1B1.

Simvastatin acid is a substrate of the transport protein OATP1B1. Concomitant administration of medicinal products that are inhibitors of the transport protein OATP1B1 may lead to increased plasma concentrations of simvastatin acid and an increased risk of myopathy (see Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Inhibitors of breast cancer resistance protein (BCRP).

Simvastatin is a substrate of the efflux transporter BCRP. Concomitant administration of products that are inhibitors of BCRP (e.g. elbasvir and grazoprevir) may lead to increased plasma concentrations of simvastatin and an increased risk of myopathy. When coadministering simvastatin with an inhibitor of BCRP, a dose adjustment of simvastatin may be necessary (see Section 4.2 Dose and Method of Administration; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Niacin (nicotinic acid) (≥ 1 g/day).

Cases of myopathy/rhabdomyolysis have been observed with simvastatin co-administered with lipid modifying doses (≥ 1 g/day) of niacin (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Colchicine.

There have been reports of myopathy and rhabdomyolysis with the concomitant administration of colchicine and simvastatin in patients with renal insufficiency. Close clinical monitoring of patients taking this combination is advised.

Daptomycin.

The risk of myopathy and/or rhabdomyolysis may be increased by coadministration of HMG-CoA reductase inhibitors and daptomycin (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Other fibrates.

The risk of myopathy is increased by gemfibrozil (see Section 4.3 Contraindications) and other fibrates (except fenofibrate); these lipid lowering drugs can cause myopathy when given alone. When simvastatin and fenofibrate are given concomitantly, there is no evidence that the risk of myopathy exceeds the sum of the individual risks of each agent (see Section 4.3 Contraindications; Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Grapefruit juice.

Grapefruit juice contains one or more components that inhibit CYP3A4 and can increase the plasma levels of drugs metabolised by CYP3A4. The effect of typical consumption (one 250 mL glass daily) is minimal (13% increase in active plasma HMG-CoA reductase inhibitory activity as measured by the area under the concentration time curve) and of no clinical relevance. However, because large quantities significantly increase the plasma levels of HMG-CoA reductase inhibitory activity, during simvastatin therapy grapefruit juice should be avoided (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).

Coumarin derivatives.

In two clinical studies, one in normal volunteers and the other in hypercholesterolaemic patients, simvastatin 20-40 mg/day modestly potentiated the effect of warfarin. The prothrombin time, reported as international normalised ratio (INR), increased from a baseline of 1.7 to 1.8 and from 2.6 to 3.4 in the volunteer and patient studies, respectively. In patients taking coumarin anticoagulants, prothrombin time should be determined before starting simvastatin and frequently enough during early therapy to ensure that no significant alteration of prothrombin time occurs. Once a stable prothrombin time has been documented, prothrombin times can be monitored at the intervals usually recommended for patients on coumarin anticoagulants. If the dose of simvastatin is changed or discontinued, the same procedure should be repeated. Simvastatin therapy has not been associated with bleeding or with changes in prothrombin time in patients not taking anticoagulants.

Propranolol.

In normal volunteers, concomitant administration of single doses of simvastatin with propranolol produced no clinically significant pharmacokinetic or pharmacodynamic interaction.

Antipyrine.

Simvastatin had no effect on the pharmacokinetics of antipyrine. However, since simvastatin is metabolised by the CYP3A4, this does not preclude an interaction with other drugs metabolised by the same isoform.

Digoxin.

Concomitant administration of simvastatin and digoxin in normal volunteers resulted in a slight elevation (less than 0.3 nanogram/mL) in plasma drug concentrations (as measured by a digoxin radioimmunoassay) compared to concomitant administration of placebo and digoxin. Patients taking digoxin should be monitored appropriately when simvastatin is initiated.

Other concomitant therapy.

In clinical studies, simvastatin was used concomitantly with beta-blockers, diuretics and nonsteroidal anti-inflammatory drugs (NSAIDs) without evidence of clinically significant adverse interactions.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

Spermatogenesis and testosterone.

In several studies of over 800 men with hypercholesterolaemia treated with simvastatin 20 mg to 80 mg per day for 12 to 48 weeks, basal testosterone levels were mildly decreased during simvastatin therapy, but there were no consistent changes in LH and FSH. In 86 men treated with simvastatin 20 mg to 80 mg per day, there was no impairment of hCG-stimulated testosterone secretion.
Testicular degeneration has been seen in two dog safety studies with simvastatin. Special studies designed to further define the nature of these changes have not met with success since the effects are poorly reproducible and unrelated to dose, serum cholesterol levels, or duration of treatment. Simvastatin has been administered for up to two years to dogs at a dose of 50 mg/kg/day without any testicular effects. Fertility of male and female rats was unaffected at oral doses of up to 25 mg/kg/day.
(Category D)
HMG-CoA reductase inhibitors, including simvastatin, are contraindicated in pregnancy. The risk of foetal injury outweighs the benefits of HMG-CoA reductase inhibitor therapy during pregnancy.
In two series of 178 and 134 cases where pregnant women took a HMG-CoA reductase inhibitor (statin) during the first trimester of pregnancy serious foetal abnormalities occurred in several cases. These included limb and neurological defects, spontaneous abortions and foetal deaths. The exact risk of injury to the foetus occurring after a pregnant woman is exposed to a HMG-CoA reductase inhibitor has not been determined. The current data do not indicate that the risk of foetal injury in women exposed to HMG-CoA reductase inhibitors is high. If a pregnant woman is exposed to a HMG-CoA reductase inhibitor she should be informed of the possibility of foetal injury and discuss the implications with her pregnancy specialist.
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 hypercholesterolaemia. Moreover, cholesterol and other products of the cholesterol biosynthesis pathway are essential components for foetal development, including synthesis of steroids and cell membranes.
Simvastatin is contraindicated during pregnancy because of the ability of inhibitors of HMG-CoA reductase such as simvastatin to decrease the synthesis of cholesterol and possibly other products of the cholesterol biosynthesis pathway. 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 and the patient informed of the potential hazard to the foetus. Animal studies showed increased incidences of foetal resorption at dosages of 50 mg/kg/day in rats and 15 mg/kg/day in rabbits. In another study, an increased incidence of skeletal malformations was observed in foetuses of rats dosed with the active metabolite of simvastatin, L-654,969, at a dose level of 60 mg/kg/day. The no effect dose level of this teratogenic activity has not been established. Other inhibitors of HMG-CoA reductase have also been shown to induce skeletal malformations in rats, and the teratogenic effects may be due to the enzyme inhibitory activity of such drugs.
The relevance of these findings to humans is not known.
 Animal studies have shown that weight gain during lactation is reduced in offspring of rats dosed with simvastatin at dosages of 12.5 to 25 mg/kg/day. There is no information from animal studies on whether simvastatin or its metabolites are excreted in breast milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions, women taking simvastatin should not breastfeed their infants (see Section 4.3 Contraindications).

4.7 Effects on Ability to Drive and Use Machines

Simvastatin has no or negligible influence on the ability to drive and use machines. However, when driving vehicles or operating machines, it should be taken into account that dizziness has been reported rarely in post-marketing experiences.

4.8 Adverse Effects (Undesirable Effects)

Simvastatin is generally well tolerated; for the most part adverse effects have been mild and transient in nature. In controlled clinical studies less than 2% of patients were discontinued due to adverse effects attributable to simvastatin.
The clinical adverse events occurring at an incidence of greater than 0.5% in controlled clinical trials and are considered to be definitely, probably or possibly due to simvastatin may be grouped as shown in Table 2.
Myopathy has been reported rarely.
In HPS (see Section 5.1 Pharmacodynamic Properties, Clinical trials) involving 20,536 patients treated with 40 mg/day of simvastatin (n = 10,269) or placebo (n = 10,267), the safety profiles were comparable between patients treated with simvastatin and patients treated with placebo over the mean 5.3 years of the study. In this trial, only serious adverse effects and discontinuations due to any adverse effects were recorded. Discontinuation rates due to side effects were comparable (4.2% in patients treated with simvastatin compared with 4.3% in patients treated with placebo). The incidence of myopathy was 0.07% in patients treated with simvastatin compared with 0.03% in patients treated with placebo. This includes rhabdomyolysis for which incidences were 0.04% in patients treated with simvastatin compared with 0.01% in patients treated with placebo. Some of these patients were taking simvastatin concomitantly with medications which are known to increase the risk of myopathy (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis). Elevated transaminases (> 3 x ULN confirmed by repeat test) occurred in 0.21% of patients treated with simvastatin compared with 0.09% of patients treated with placebo.
In 4S (see Section 5.1 Pharmacodynamic Properties, Clinical trials) involving 4,444 patients treated with 20-40 mg/day of simvastatin (n = 2,221) or placebo (n = 2,223), the safety and tolerability profiles were comparable between treatment groups over the median 5.4 years of the study.
The following rare (≥ 1/10,000, ˂ 1/1000) or very rare (˂ 1/10,000) adverse experiences were reported in patients taking simvastatin:

Eye disorders.

Rare: vision blurred, visual impairment.

Skin and subcutaneous tissue disorders.

Very rare: lichenoid drug eruptions.

Musculoskeletal and connective tissue disorders.

Very rare: muscle rupture.

Reproductive system and breast disorders.

Very rare: gynaecomastia.
The following additional adverse effects were reported either in uncontrolled clinical trials or in marketed use: pruritus, alopecia, dizziness, muscle cramps, myalgia, depression, pancreatitis, paraesthesia, peripheral neuropathy, insomnia, vomiting, anaemia, erectile dysfunction, and interstitial lung disease.
There have been very 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 (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).
Rhabdomyolysis and hepatitis/jaundice occurred rarely and fatal and non-fatal hepatic failure occurred very rarely. An apparent hypersensitivity syndrome that included some of the following features has been reported rarely: anaphylaxis, angioedema, lupus-like syndrome, polymyalgia rheumatica, dermatomyositis, vasculitis, thrombocytopenia, eosinophilia, ESR increased, arthritis, arthralgia, urticaria, photosensitivity, fever, flushing, dyspnoea and malaise.
There have been rare postmarketing reports of cognitive impairment (e.g. memory loss, forgetfulness, amnesia, memory impairment, confusion) associated with statin use. These cognitive issues have been reported for all statins. The reports are generally nonserious, and reversible upon statin discontinuation, with variable times to symptom onset (1 day to years) and symptom resolution (median of 3 weeks).

Laboratory test findings.

Marked and persistent increases of serum transaminases have been reported infrequently. Elevated alkaline phosphatase and γ-glutamyl transpeptidase have been reported. Liver function test abnormalities have generally been mild and transient. Increases in serum CK levels, derived from skeletal muscle have been reported (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).
Increases in HBA1c and fasting serum glucose levels have been reported with statins, including simvastatin.

Paediatric patients (aged 10-17 years).

In a study involving paediatric patients 10-17 years of age with heterozygous familial hypercholesterolaemia (n=175), the safety and tolerability profile of the group treated with simvastatin was generally similar to that of the group treated with placebo (see Section 4.4 Special Warnings and Precautions for Use, Paediatric use).

Adverse effects - causal relationship unknown.

The following adverse effects have been reported, however, a causal relationship to therapy with simvastatin has not been established: erythema multiforme including Stevens-Johnson syndrome, leucopenia, impotence, proteinuria, and purpura.

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at http://www.tga.gov.au/reporting-problems and contact Apotex Medical Information enquiries/Adverse Drug Reaction Reporting on 1800 195 055.

4.9 Overdose

A few cases of overdosage have been reported; all patients recovered without sequelae. The maximum dose taken was 3.6 g. General measures should be adopted, and liver function should be monitored.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Mechanism of action.

The involvement of low density lipoprotein cholesterol (LDL-C) in atherogenesis has been well documented in clinical and pathological studies, as well as in many animal experiments. Epidemiological studies have established that high LDL-C and low high density lipoprotein cholesterol (HDL-C) are both risk factors for coronary heart disease (CHD).
After oral ingestion, simvastatin, which is an inactive lactone, is hydrolysed to the corresponding β-hydroxyacid form. This is a principal metabolite and an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an enzyme which catalyses an early and rate limiting step in the biosynthesis of cholesterol. As a result, in clinical studies simvastatin reduced total plasma cholesterol (total-C), LDL-C and very low density lipoprotein cholesterol (VLDL-C) concentrations. In addition, simvastatin increases HDL-C and reduces plasma triglycerides (TG).
Simvastatin has been shown to reduce both normal and elevated LDL-C concentrations. LDL is formed from VLDL and is catabolised predominantly by the high affinity LDL receptor. The mechanism of the LDL lowering effect of simvastatin may involve both reduction of VLDL-C concentration and induction of the LDL receptor, leading to reduced production and increased catabolism of LDL-C. Apolipoprotein B (Apo B) also falls substantially during treatment with simvastatin. Since each LDL particle contains one molecule of Apo B, and since little Apo B is found in other lipoproteins, this strongly suggests that simvastatin does not merely cause cholesterol to be lost from LDL, but also reduces the concentration of circulating LDL particles. As a result of these changes the ratios of total-C to HDL-C and LDL-C to HDL-C are reduced.
Even though simvastatin is a specific inhibitor of HMG-CoA reductase, the enzyme which catalyses the conversion of HMG-CoA to mevalonate is not completely blocked at therapeutic doses, therefore it allows the necessary amounts of mevalonate to be available for biological functions. Because the conversion of HMG-CoA to mevalonate is an early step in the biosynthetic pathway of cholesterol, therapy with simvastatin would not be expected to cause an accumulation of potentially toxic sterols. In addition, HMG-CoA is metabolised readily back to acetyl-CoA, which participates in many biosynthetic processes in the body.

Clinical trials.

Simvastatin has been studied in the treatment of primary hypercholesterolaemia where diet alone has been insufficient. Simvastatin was highly effective in reducing total-C and LDL-C in heterozygous familial (Fredrickson type IIa) and non-familial forms of hypercholesterolaemia, and in mixed hyperlipidaemia (Fredrickson type IIb) when elevated cholesterol was a cause of concern. A marked response was seen within 2 weeks and the maximum therapeutic response occurred within 4-6 weeks. The response has been maintained during continuation of therapy. In six controlled clinical studies involving approximately 1700 patients with normal or slightly raised TG (mean 1.9 mmol/L), plasma TG, VLDL-C and Apo B decreased in all studies in a dose dependent manner. In two of these studies in patients with hypercholesterolaemia receiving simvastatin 20 or 40 mg/day for 12 weeks, the following results were observed. See Table 3.
In a separate study involving 180 patients with combined hyperlipidaemia, simvastatin 10 mg/day for 17 weeks was also shown to be effective in lowering total-C, LDL-C, VLDL-C, TGs and Apo B (see Table 4).
The data from these studies demonstrate that in patients with hypercholesterolaemia and normal or slightly raised TG, simvastatin consistently reduces total-C, LDL-C, TG, VLDL-C and Apo B in a dose dependent manner.
The results of 4 separate studies depicting the dose response to simvastatin in patients with primary hypercholesterolaemia are presented in Table 5.
In the upper dose comparative study, one-third of patients obtained a reduction in LDL-C of 53% or more at the 80 mg dose. The percent reduction in LDL-C was essentially independent of the baseline level. In contrast, the percent reduction in TG was related to the baseline level of TG. Of the 664 patients randomised to 80 mg, 475 patients with plasma TG ≤ 2.25 mmol/L had a median reduction in TG of 21%, while in 189 patients with hypertriglyceridaemia (> 2.25 mmol/L), the median reduction in TG was 36%. In these studies, patients with TG > 4.0 mmol/L were excluded.
In a controlled clinical study, 12 patients 15-39 years of age with homozygous familial hypercholesterolaemia received simvastatin 40 mg/day in a single dose or in 3 divided doses, or 80 mg/day in 3 divided doses of 20 mg, 20 mg, and an evening dose of 40 mg. The mean LDL-C reductions for the 40 mg and 80 mg doses were 14% and 25%, respectively. One of the twelve patients in this study had complete absence of LDL receptor function (receptor 'deficient'). In this patient, LDL-C reduction of 41% occurred with the 80 mg dose. The magnitude of response to therapy with simvastatin was not predictable by the LDL-receptor gene defects as patients with some LDL-receptor mutations responded differently to the same dose of simvastatin therapy. Five of the twelve patients were also receiving probucol.
The value of drug and/or diet induced reduction in plasma cholesterol is no longer controversial. The benefits of reducing LDL-C on morbidity and mortality due to CHD have been established. The Lipid Research Clinics Coronary Primary Prevention Trial (LRC-CPPT) demonstrated in a seven year, double blind, placebo controlled study that lowering LDL-C with diet and cholestyramine decreased the combined incidence of CHD death plus non-fatal myocardial infarction (MI).
In a randomised, double blind, 3 period crossover study, 130 patients with combined hyperlipidaemia (LDL-C > 3.4 mmol/L and TG 3.4-7.9 mmol/L) were treated with placebo, simvastatin 40 and 80 mg/day for 6 weeks. In a dose dependent manner simvastatin 40 and 80 mg/day, respectively, decreased mean LDL-C by 29 and 36% (placebo 2%) and median TG levels by 28 and 33% (placebo 4%), and increased mean HDL-C by 13 and 16% (placebo 3%) and apolipoprotein A-1 by 8 and 11% (placebo 4%).
In the Scandinavian Simvastatin Survival Study (4S), simvastatin reduced the risk of death, coronary death, non-fatal MI and undergoing myocardial revascularisation procedures (coronary artery bypass grafting and percutaneous transluminal coronary angioplasty) in patients with CHD and hypercholesterolaemia.
In 4S the effect of therapy with simvastatin on total mortality was assessed in 4,444 patients with CHD and baseline total C 5.5-8.0 mmol/L. In this multicentre, randomised, double blind, placebo controlled study, patients with angina or a previous MI were treated with diet and standard care and either with simvastatin 20-40 mg daily (n = 2,221) or placebo (n = 2,223) for a median duration of 5.4 years. Eighty two percent (82%) of the subjects were male. Over the course of the study, treatment with simvastatin led to mean reductions in total-C, LDL-C and TG of 25%, 35%, and 10% respectively, and a mean increase in HDL-C of 8%. Simvastatin reduced the risk of death by 30%, 95% confidence interval 15-42%, p=0.0003 (182 deaths in the simvastatin group vs 256 deaths in the placebo group). The risk of CHD death was reduced by 42%, 95% CI 27-54%, p=0.00001 (111 vs 189). Simvastatin also decreased the risk of having major coronary events (CHD death plus hospital verified and silent non-fatal MI) by 34%, 95% CI 25-41%, p < 0.00001 (431 patients vs 622 patients with one or more events). The risk of having a hospital verified non-fatal MI was reduced by 37%. Simvastatin reduced the risk for undergoing myocardial revascularisation procedures (coronary artery bypass grafting or percutaneous transluminal coronary angioplasty) by 37%, 95% CI 26-46%, p < 0.00001 (252 patients vs. 383 patients).
Furthermore, simvastatin significantly reduced the risk of fatal plus non-fatal cerebrovascular events (stroke and transient ischaemic attacks) by 28%, 95% CI 3-46% (p=0.033, 75 patients vs 102 patients). There was no statistically significant difference between groups in noncardiovascular mortality. Simvastatin reduced the risk of major coronary events to a similar extent across the range of baseline total-C and LDL-C levels.
The risk of death in patients ≥ 60 years of age was decreased by 27% and in patients < 60 years of age by 37%, 95% CI 12-55% (p < 0.01 in both age groups). The effect of simvastatin on mortality in women could not be adequately assessed, because there were only 53 female deaths. However, simvastatin lessened the risk of having major coronary events by 34%, 95% CI 9-52% (p=0.012, 60 women vs 91 women with one or more event). In a post hoc analysis in patients with diabetes mellitus and CHD, the risk of major coronary events was reduced by 55%, 95% CI 24-73% (p=0.002, 24 patients vs 44 patients). Since there were only 39 deaths among diabetic patients (15 among simvastatin treated patients and 24 among placebo treated patients), the effect of simvastatin on mortality in diabetic patients could not be adequately assessed. It should be noted that 4S excluded patients with triglycerides > 2.5 mmol/L or with severe cardiac or renal disease.
In the Multicenter Anti-Atheroma Study (MAAS), the effect of therapy with simvastatin on coronary atherosclerosis was assessed by quantitative coronary angiography in hypercholesterolaemic men and women with coronary heart disease. In this randomised, double blind, controlled clinical trial, 404 patients with total-C values of 5.5 to 8.0 mmol/L and a mean baseline LDL-C value of 4.4 mmol/L were treated with conventional measures and with simvastatin 20 mg/day or placebo. Eighty nine percent (89%) of the subjects were male. Angiograms were evaluated at baseline, two and four years. A total of 347 patients had a baseline angiogram and at least one follow-up angiogram. In the patients who received placebo, coronary atherosclerotic lesions worsened in a near linear manner.
In contrast, simvastatin significantly slowed the progression of lesions as measured in the final angiogram by the mean change per patient in minimum (p=0.005) and mean (p=0.026) lumen diameters (co-primary endpoints, indicating focal and diffuse disease, respectively), as well as in percent diameter stenosis (p=0.003). Simvastatin also significantly decreased the proportion of patients with new lesions (13% simvastatin vs 24% placebo, p=0.009) and with new total occlusions (5% vs 11%, p=0.04). In interpreting these results, it is important to be aware of the limitations of angiography, which may underestimate the extent and severity of atherosclerosis. In addition, angiography cannot be used to predict the site of future coronary occlusion. Acute ischaemic events tend to occur not at the site of severe stenoses but at lesser stenoses which are lipid rich, soft and more prone to rupture.
In MAAS, simvastatin slowed the progression of coronary atherosclerosis and reduced the development of both new lesions and new total occlusions, whereas coronary atherosclerotic lesions steadily worsened over four years in patients receiving standard care.

High risk of coronary heart disease (CHD) or existing coronary heart disease.

The Heart Protection Study (HPS) was a large, multicenter, randomised, placebo controlled, double blind study with a mean duration of 5.3 years conducted in 20,536 patients (10,269 on simvastatin 40 mg and 10,267 on placebo). Patients were 40-80 years of age and at high risk of developing a major coronary event based on 3 main categories of past medical history: coronary disease (definite or probable clinical diagnosis of MI, unstable angina, stable angina, PTCA or CABG); occlusive disease of non-coronary arteries (clinical, angiographic or ultrasound diagnosis of carotid artery stenosis (e.g. TIA or non-disabling stroke not thought to be haemorrhagic), carotid endarterectomy, leg artery stenosis (e.g. intermittent claudication) or surgery; or diabetes mellitus (clinical diagnosis of insulin dependent or maturity onset diabetes). LDL-C levels were assayed using a direct method and collected without regard for meals (results are about 5% lower than fasting sample). At baseline, 3,421 patients (17%) had LDL-C levels below 2.6 mmol/L; 7,068 patients (34%) had levels greater than 2.6 mmol/L and less than 3.4 mmol/L; and 10,047 patients (49%) had levels greater than or equal to 3.4 mmol/L. At baseline, 2,030 (19.8%) patients in the simvastatin group and 2,042 (19.9%) in the placebo group had total-C less than 5.0 mmol/L; 3,942 (38.4%) patients in the simvastatin group and 3,941 (38.4%) in the placebo group had levels greater than or equal to 5.0 mmol/L and less than 6.0 mmol/L; and 4,297 (41.8%) patients in the simvastatin group and 4,284 (41.7%) in the placebo group had levels greater than or equal to 6.0 mmol/L.
The major cardiovascular events prevented were non-fatal myocardial infarction, CHD death, stroke and revascularisation procedures. The HPS results showed that simvastatin 40 mg/day significantly reduced total and CHD mortality (with no evidence of any increase in non-CHD mortality); major coronary events (a composite endpoint comprised of non-fatal MI or CHD deaths); stroke; coronary revascularisation procedures; hospitalisation for angina; and major vascular events, a composite endpoint which was comprised of major coronary events, stroke, or revascularisation procedures (see Table 6). Risk reductions of approximately one-quarter were observed for major vascular events, major coronary events, and stroke. These risk reductions are underestimates due to the fact that 33% of the patients in the intention to treat analysis did not comply with the study protocol (i.e. patients allocated placebo took a statin, or patients allocated simvastatin did not take the study drug). Thus, by five years, simvastatin taken consistently would be expected to reduce the risk of these events by about one-third.
The effects of simvastatin on major vascular events and major coronary events were similar in all subgroups of patients (see Figure 1).
The risk reductions produced by simvastatin in both major coronary events and major vascular events were evident and consistent across all baseline characteristics shown in Figure 1. In addition, these risk reductions were evident and consistent regardless of prior treated hypertension, creatinine levels up to the entry limit of 2.3 mg/dL, apolipoprotein A-I and B levels, baseline concomitant cardiovascular medications (i.e. ASA, beta-blockers, ACE inhibitors, or calcium channel blockers), smoking status, alcohol intake, or obesity.

Hypertriglyceridaemia (Fredrickson type IV hyperlipidaemia).

The results of subgroup analyses from a study including a total of 116 patients with hypertriglyceridaemia (Fredrickson type IV hyperlipidaemia) are presented in Table 7. This study was a double blind, placebo controlled, parallel study comparing simvastatin 20, 40, and 80 mg/day with placebo. Each treatment group included approximately 30 patients. The respective baseline values for the type IV patients were: total C = 6.04 mmol/L; LDL-C = 2.59 mmol/L; HDL-C = 0.91 mmol/L; TG 5.01 mmol/L; VLDL-C = 2.44 mmol/L; non-HDL-C = 5.13 mmol/L. The study demonstrated that simvastatin at doses of 20 to 80 mg/day reduced TG 21 to 33% (placebo: 13%), LDL-C 23 to 35% (placebo +3%), non-HDL-C 26 to 41% (placebo: 1%), and raised HDL-C by 9 to 11% (placebo: 3%).

Dysbetalipoproteinaemia (Fredrickson type III hyperlipidaemia).

Table 8 presents the subgroup analysis results of 7 patients with Fredrickson type lll hyperlipidaemia (dysbetalipoproteinaemia; apo E2/2 and VLDL-C/TG > 0.25) from a 130-patient double-blind, placebo-controlled, 3-period crossover study. In this study the median baseline values were: total-C = 324 mg/dL (8.39 mmol/L), LDL-C (+IDL) = 121 (3.13), HDL-C = 31 (0.80), TG = 411 (4.67), VLDL-C (+IDL) = 170 (4.40), and non-HDL-C = 291 (7.54). At a dosage of 80 mg/day, simvastatin reduced LDL-C including intermediate-density lipoproteins (IDL) by 50% (placebo: 8%) and VLDL-C + IDL by 59% (placebo: 4%).

5.2 Pharmacokinetic Properties

The inhibition of HMG-CoA reductase is the basis for an assay in pharmacokinetic studies of the β-hydroxyacid metabolites (active inhibitors) and, following base hydrolysis, active plus latent inhibitors (total inhibitors). Both are measured in plasma following administration of simvastatin.

Absorption.

In a disposition study with 14C-labelled simvastatin, 100 mg (20 microCi) of drug was administered as capsules (5 x 20 mg) and blood, urine and faeces collected. Thirteen percent of the radioactivity was recovered in the urine and 60% in faeces. The latter represents absorbed drug equivalents excreted in bile as well as unabsorbed drug. Less than 0.5% of the dose was recovered in urine as HMG-CoA reductase inhibitors. In plasma, the inhibitors account for 14% and 28% (active and total inhibitors) of the AUC of total radioactivity, indicating that the majority of chemical species present were inactive or weak inhibitors.
Both simvastatin and β-hydroxyacid are bound to human plasma proteins (95%). The availability of β-hydroxyacid to the systemic circulation following an oral dose of simvastatin was estimated using an I.V. reference dose of β-hydroxyacid; the value was found to be less than 5 percent of the dose.
By analogy to a dog model, simvastatin is well absorbed and undergoes extensive first-pass extraction in the liver, the primary site of action, with subsequent excretion of drug equivalents in the bile. Consequently, availability of active drug to the general circulation is low.

Distribution.

No data available.

Metabolism.

The major metabolites of simvastatin present in human plasma are β-hydroxyacid and four additional active metabolites. Simvastatin and other HMG-CoA reductase inhibitors are metabolised by CYP3A4 (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis). In dose proportionality studies utilising doses of simvastatin of 5, 10, 20, 60, 90 and 120 mg there was no substantial deviation from linearity of AUC of inhibitors in the general circulation with an increase in dose. Relative to the fasting state, the plasma profile of inhibitors was not affected when simvastatin was administered immediately before a test meal.
The pharmacokinetics of single and multiple doses of simvastatin showed that no accumulation of drug occurred after multiple dosing. In all of the above pharmacokinetic studies, the maximum plasma concentration of inhibitors occurred 1.3 to 2.4 hours postdose.
Although the mechanism is not fully understood, ciclosporin has been shown to increase the AUC of HMG-CoA reductase inhibitors. The increase in AUC for simvastatin acid is presumably due, in part, to inhibition of CYP3A4 and/or OATP1B1.
The pharmacokinetic effects of calcium channel blockers on simvastatin and HMG-CoA reductase inhibitors are summarised in Table 9. The data show increases in simvastatin acid exposure (AUC) with calcium channel blockers (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis).
A single dose of 2 g niacin extended release coadministered with 20 mg simvastatin increased the AUC and Cmax of simvastatin acid by approximately 60% and 84%, respectively, compared to administration of 20 mg simvastatin alone. In this study, the effect of simvastatin on niacin pharmacokinetics was not measured.
The risk of myopathy is increased by high levels of HMG-CoA reductase inhibitory activity in plasma. Potent inhibitors of CYP3A4 can raise the plasma levels of HMG-CoA reductase inhibitory activity and increase the risk of myopathy (see Section 4.4 Special Warnings and Precautions for Use, Myopathy/rhabdomyolysis; Section 4.5 Interactions with Other Medicines and Other Forms of Interactions).

Excretion.

See Section 5.2 Pharmacokinetic Properties, Absorption.

5.3 Preclinical Safety Data

Genotoxicity.

Genetic toxicology studies of simvastatin showed no evidence of mutagenic activity in bacteria or in mammalian cells in vitro, or of clastogenic activity in vitro or in mice in vivo. In vitro and in vivo assays showed that simvastatin does not cause DNA damage in rat hepatocytes.

Carcinogenicity.

In animal studies.

Carcinogenicity studies have been conducted in mice at oral doses ranging from 1 to 400 mg/kg/day and in rats at doses of 1 to 100 mg/kg/day. Hepatocellular adenomas and carcinomas were observed in both sexes of both species at doses greater than 25 mg/kg/day. Plasma drug levels in rats at this no effect dose level, expressed as the AUC for enzyme inhibitory activity, were 3 to 11 times greater than in humans at the maximum recommended dose, whereas serum levels at the no effect level in mice were similar to those in humans. Additional findings in mice were increased incidences of pulmonary adenomas at doses greater than 25 mg/kg/day, and of Harderian gland adenomas at 400 mg/kg/day. In rats, the incidence of thyroid follicular adenoma was increased in females at dose greater than 5 mg/kg/day and in males at doses greater than 25 mg/kg/day. These thyroid tumours were associated with focal cystic follicular hyperplasia and may be a secondary effect reflective of a simvastatin mediated enhancement of thyroid hormone clearance by the liver.

6 Pharmaceutical Particulars

6.1 List of Excipients

Lactose monohydrate, microcrystalline cellulose, pregelatinised maize starch, ascorbic acid, citric acid monohydrate, butylated hydroxyanisole, magnesium stearate, Opadry 20A54692 Pink (10 mg only), Opadry 20A56767 Brown (20 mg only), Opadry 20A54535 Pink (40 mg and 80 mg only).

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Store below 25°C. Protect from moisture.

6.5 Nature and Contents of Container

10 mg tablets.

Blister packs (PVC/PVDC/Al) of 30 tablets (AUST R 211952).

20 mg tablets.

Blister packs (PVC/PVDC/Al) of 30 tablets (AUST R 211953).

40 mg tablets.

Blister packs (PVC/PVDC/Al) of 30 tablets (AUST R 211954).

80 mg tablets.

Blister packs (PVC/PVDC/Al) of 30 tablets (AUST R 211955).

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Chemical structure.

Structural Formula:
Chemical Name: [1S-[1α, 3α, 7β, 8β (2S*,4S*), 8αβ]]-1,2,3,7,8,8a-hexahydro-3,7-dimethyl-8-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl) ethyl]-1-naphthalenyl 2,2-dimethylbutanoate.
Molecular Formula: C25H38O5.
Molecular Weight: 418.57.

CAS number.

79902-63-9.

7 Medicine Schedule (Poisons Standard)

S4 - Prescription Only Medicine.

Summary Table of Changes