Viread 245 mg film-coated tablets

 

What is it and how is it used?

Viread is a treatment for Human Immunodeficiency Virus (HIV) infection in adults over 18 years of age.

Viread is also used to treat chronic hepatitis B, an infection with hepatitis B virus (HBV), in adults.

You do not have to have HIV to be treated with Viread for HBV.

Viread contains the active substance, tenofovir disoproxil. This active substance is an antiretroviral or antiviral medicine which is used to treat HIV or HBV or both. Tenofovir is a nucleotide reverse transcriptase inhibitor, generally known as an NRTI and works by interfering with the normal working of enzymes (in HIV reverse transcriptase; in hepatitis B DNA polymerase) that are essential for the viruses to reproduce themselves. In HIV Viread should always be used combined with other medicines to treat HIV infection.

This medicine is not a cure for HIV infection. While taking Viread you may still develop infections or other illnesses associated with HIV infection.

You can also pass on HIV or HBV to others, so it is important to take precautions to avoid infecting other people.

What do you have to consider before using it?

Do not take Viread

  • If you are allergic (hypersensitive) to tenofovir, tenofovir disoproxil fumarate or any of the other ingredients of Viread listed at the end of this leaflet.

If this applies to you, tell your doctor immediately and don’t take Viread.

Take special care with Viread

  • Tell your doctor if you have had kidney disease or if tests have shown problems with your kidneys. Viread may affect your kidneys. Before starting treatment, your doctor may order blood tests to check your kidney function and may advise you to take the tablets less often. Your doctor may also order blood tests during treatment to monitor your kidneys.

Viread is not usually taken with other medicines that can damage your kidneys (see Taking other medicines). If this is unavoidable, your doctor will monitor your kidney function once a week.

  • Talk to your doctor if you are over 65. Viread has not been studied in patients over 65 years of age. If you are older than this and are prescribed Viread, your doctor will monitor you carefully.
  • Do not give Viread to children and adolescents under 18 years of age.
  • Talk to your doctor if you have a history of liver disease, including hepatitis. Patients with liver disease including chronic hepatitis B or C, who are treated with antiretrovirals, have a higher risk of severe and potentially fatal liver complications. If you have hepatitis B infection, your doctor will carefully consider the best treatment for you. If you have a history of liver disease or chronic hepatitis B infection your doctor may conduct blood tests to monitor your liver function.

Look out for possible signs of lactic acidosis (excess of lactic acid in your blood) once you start taking Viread. Possible signs of lactic acidosis are:

  • Deep, rapid breathing
  • drowsiness
  • nausea, vomiting and stomach pain
  • This rare but serious side effect can cause enlargement of the liver and has occasionally been fatal. Lactic acidosis occurs more often in women, particularly if they are very overweight. If you have liver disease you may also be more at risk of getting this condition. While you are being treated with Viread, your doctor will monitor you closely for any signs that you may be developing lactic acidosis.
  • Take care not to infect other people. Viread does not reduce the risk of passing on HIV or HBV to others through sexual contact or blood contamination. You must continue to take precautions to avoid this.

Other precautions

In the treatment of HIV, combination antiretroviral therapies (including Viread) may raise blood sugar, increase blood fats (hyperlipaemia), cause changes to body fat, and resistance to insulin (see section 4, Possible side effects).

If you are diabetic, overweight or have high cholesterol, talk to your doctor.

Look out for infections. If you have advanced HIV infection (AIDS) and have an infection, you may develop symptoms of infection and inflammation or worsening of the symptoms of an existing infection once treatment with Viread is started. These symptoms may indicate that your body’s improved immune system is fighting infection. Look out for signs of inflammation or infection soon after you start taking Viread. If you notice signs of inflammation or infection, tell your doctor at once.

Bone problems. Some patients with HIV taking combination antiretroviral therapy may develop a bone disease called osteonecrosis (death of bone tissue caused by loss of blood supply to the bone). The length of combination antiretroviral therapy, corticosteroid use, alcohol consumption, severe immunosuppression, higher body mass index, among others, may be some of the many risk factors for developing this disease. Signs of osteonecrosis are joint stiffness, aches and pains (especially of the hip, knee and shoulder) and difficulty in movement. If you notice any of these symptoms tell your doctor.

Bone problems (sometimes resulting in fractures) may also occur due to damage to kidney tubule cells (see section 4, Possible side effects).

Taking other medicines

Tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription.

  • Don’t stop any anti-HIV medicines prescribed by your doctor when you start Viread if you have both HBV and HIV.
  • Do not take Viread if you are already taking other medicines containing tenofovir disoproxil fumarate. Do not take Viread and Hepsera (adefovir dipivoxil) at the same time.
  • It is very important to tell your doctor if you are taking other medicines that may damage your kidneys.

These include:

  • aminoglycosides, pentamidine or vancomycin (for bacterial infection)
  • amphotericin B (for fungal infection)
  • foscarnet, ganciclovir, or cidofovir (for viral infection)
  • interleukin-2 (to treat cancer)
  • adefovir dipivoxil (for HBV)
  • tacrolimus (for suppression of the immune system)
  • Other medicines containing didanosine (for HIV infection): Taking Viread with other antiviral medicines that contain didanosine can raise the levels of didanosine in your blood and may reduce CD4 cell counts. Rarely, inflammation of the pancreas and lactic acidosis (excess lactic acid in the blood), which sometimes caused death, have been reported when medicines containing tenofovir disoproxil fumarate and didanosine were taken together. Your doctor will carefully consider whether to treat you with combinations of tenofovir and didanosine.

Taking Viread with food and drink

  • Take Viread with food (for example, a meal or a snack).

Pregnancy and breast-feeding

Ask your doctor or pharmacist for advice before taking any medicine.

  • You must not take Viread during pregnancy unless specifically discussed with your doctor. There are no clinical data on the use of Viread in pregnant women and it is not usually used unless absolutely necessary.
  • Try to avoid getting pregnant during treatment with Viread. You must use an effective method of contraception to avoid becoming pregnant.
  • If you become pregnant, or plan to become pregnant, ask your doctor about the potential benefits and risks of your antiretroviral therapy to you and your child.
  • If you have taken Viread during your pregnancy, your doctor may request regular blood tests and other diagnostic tests to monitor the development of your child. In children whose mothers took medicines like Viread (NRTIs) during pregnancy, the benefit from the protection against the virus outweighed the risk of side effects.
  • Do not breast-feed during treatment with Viread. It is not yet known whether the active substance in this medicine passes into human breast milk.
  • If you are a woman with HIV or HBV do not breast-feed, to avoid passing the virus to the baby in breast milk.

Driving and using machines
Viread can cause dizziness. If you feel dizzy while taking Viread, do not drive and do not use any tools or machines.

Important information about some of the ingredients of Viread

Viread contains lactose. Tell your doctor before taking Viread if you cannot tolerate lactose or if you have an intolerance to any other sugars.

How is it used?

  • Always take Viread exactly as your doctor has told you. You should check with your doctor or pharmacist if you are not sure.

The usual dose:

  • Adults: one tablet each day with food (for example, a meal or a snack).
  • Not for children and adolescents (under 18 years of age).

If you have particular difficulty swallowing, you can use the tip of a spoon to crush the tablet. Then mix the powder with about 100 ml (half a glass) of water, orange juice or grape juice and drink immediately.

  • Always take the dose recommended by your doctor. This is to make sure that your medicine is fully effective, and to reduce the risk of developing resistance to the treatment. Do not change the dose unless your doctor tells you to.
  • If you have problems with your kidneys, your doctor may advise you to take Viread less frequently.
  • Don’t stop any anti-HIV medicines prescribed by your doctor when you start Viread if you have both HBV and HIV.
  • If you have HBV your doctor may offer you an HIV test to see if you have both HBV and HIV.

Please refer to the patient information leaflets of the other antiretrovirals for guidance on how to take those medicines.

If you take more Viread than you should

If you accidentally take too many Viread tablets, contact your doctor or nearest emergency department for advice. Keep the tablet bottle with you so that you can easily describe what you have taken.

If you forget to take Viread

It is important not to miss a dose of Viread.

If you miss a dose of Viread, take it as soon as you can, and then take your next dose at its regular time.

If it is almost time for your next dose anyway, forget about the missed dose. Wait and take the next dose at the regular time. Do not take a double dose to make up for a forgotten tablet.

If you throw up less than 1 hour after taking Viread, take another tablet. You do not need to take another tablet if you were sick more than 1 hour after taking Viread.

If you stop taking Viread

  • Don’t stop taking Viread without your doctor’s advice. Stopping treatment with Viread may reduce the effectiveness of the treatment recommended by your doctor. Talk to your doctor before you stop taking Viread for any reason, particularly if you are experiencing any side effects or you have another illness. Contact your doctor before you restart taking Viread tablets.
  • If you have hepatitis B or HIV and hepatitis B together (co-infection), it is very important not to stop your Viread treatment without talking to your doctor first. Some patients have had blood tests or symptoms indicating that their hepatitis has got worse after stopping Viread. You may require blood tests for several months after stopping treatment. In some patients with advanced liver disease or cirrhosis, stopping treatment is not recommended as this may lead to worsening of your hepatitis.

Tell your doctor immediately about new or unusual symptoms after you stop treatment, particularly symptoms you associate with hepatitis B infection.

If you have any further questions on the use of this product, ask your doctor or pharmacist.

What are possible side effects?

Like all medicines, Viread can cause side effects, although not everybody gets them.

Very common side effects
(These can affect at least 10 in every 100 patients)

  • diarrhoea, being sick (vomiting), feeling sick (nausea), dizziness, rash, feeling weak

Tests may also show:

  • decreases in phosphate in the blood

Common side effects
(These can affect up to 10 in every 100 patients)

  • headache, stomach pain, feeling tired, feeling bloated, flatulence

Tests may also show:

  • liver problems

Uncommon side effects
(These can affect up to 1 in every 100 patients)

  • pain in the tummy (abdomen) caused by inflammation of the pancreas
  • breakdown of muscle, muscle pain or weakness

Tests may also show:

  • decreases in potassium in the blood
  • increased creatinine in your blood
  • pancreas problems

The breakdown of muscle, softening of the bones (with bone pain and sometimes resulting in fractures), muscle pain, muscle weakness and decreases in potassium or phosphate in the blood may occur due to damage to kidney tubule cells.

Rare side effects
(These can affect up to 1 in every 1,000 patients)

  • excess lactic acid in the blood (lactic acidosis, a serious side effect that can be fatal). The following side effects may be signs of lactic acidosis:
  • deep rapid breathing
  • drowsiness
  • feeling sick (nausea), being sick (vomiting) and stomach pain

If you think you may have lactic acidosis, contact your doctor immediately.

  • pain in the tummy (abdomen) caused by inflammation of the liver
  • softening of the bones (with bone pain and sometimes resulting in fractures)
  • inflammation of the kidney, passing a lot of urine and feeling thirsty, damage to kidney tubule cells
  • changes to your urine and back pain caused by kidney problems, including kidney failure
  • swelling of the face, lips, tongue or throat
  • fatty liver

Other possible effects

In the treatment of HIV, combination antiretroviral therapy (including Viread) may change your body shape, by changing the way body fat is distributed. You may lose fat from your legs, arms and face; gain fat around the tummy (abdomen) and internal organs; get larger breasts or fatty lumps on the back of the neck (‘buffalo hump’). The cause and the long-term effects of these changes are not yet known.

In the treatment of HIV, combination antiretroviral therapy may also cause increased fats in the blood (hyperlipaemia) and resistance to insulin. Your doctor will test for these changes.

If any of the side effects get serious, or if you notice any side effects not listed in this leaflet, please tell your doctor.

How should it be stored?

Keep out of the reach and sight of children.

Do not use Viread after the expiry date which is stated on the bottle and carton after {EXP}. The expiry date refers to the last day of that month.

This medicine does not require any special storage conditions.

Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help to protect the environment.

What is it?

Viread is a medicine containing the active substance tenofovir disoproxil. It is available as light blue almond-shaped tablets (245 mg).

What is it used for?

Viread is used to treat adults aged over 18 years who are infected with the following viruses:

human immunodeficiency virus type 1 HIV 1, a virus that causes acquired immune deficiency syndrome AIDS. Viread is taken in combination with other antiviral medicines. For patients who have taken medicines to treat HIV infection before, doctors should only prescribe Viread once they have looked at the antiviral medicines the patient has taken before or the likelihood of the viruss response to antiviral medicines.

hepatitis B virus, a virus that can cause hepatitis B a disease of the liver. Viread is used in patients with chronic long-term infection whose liver is damaged. This includes patients whose liver has stopped working properly and those whose liver may still be working properly but show signs of liver damage in the blood and in liver tissue samples.

The medicine can only be obtained with a prescription.

How is it used?

Treatment with Viread should be initiated by a doctor who has experience in the treatment of HIV infection or chronic hepatitis B. The recommended dose of Viread is one tablet taken once a day with food. In exceptional cases, patients who have particular difficulty swallowing can crush the tablet in at least 100 ml of water, orange juice or grape juice, and drink the resulting suspension. In patients with kidney problems, Viread should only be used if the expected benefits of the medicine outweigh its risks. The frequency of dosing may need to be reduced in patients who have moderate or severe problems with their kidneys.

Patients who are infected with the hepatitis B virus, with or without HIV, should be monitored closely for flare-ups of hepatitis (liver inflammation) if they stop taking Viread.

How does it work?

The active substance in Viread, tenofovir disoproxil, is a ‘prodrug’ that is converted into tenofovir in the body.

Tenofovir is a nucleotide reverse transcriptase inhibitor (NRTI). In HIV infection, it blocks the activity of reverse transcriptase, an enzyme produced by HIV that allows it to infect cells and make more viruses. Viread, taken in combination with other antiviral medicines, reduces the amount of HIV in the blood and keeps it at a low level. Viread does not cure HIV infection or AIDS, but it may delay the damage to the immune system and the development of infections and diseases associated with AIDS.

Tenofovir also interferes with the action of an enzyme produced by the hepatitis B virus called ‘DNA polymerase’, which is involved in the formation of viral DNA. Viread stops the virus making DNA and prevents it from multiplying and spreading.

How has it been studied?

For the treatment of HIV, Viread has been studied in three main studies involving 1,343 HIV-infected adults. The first two studies compared the effects of adding Viread with those of adding placebo (a dummy treatment) to existing treatment in 741 patients who had been taking HIV treatments for at least four years, but were not responding to them. Viread was also assessed in a study of 602 treatment-naïve patients (who had not taken HIV treatment before), comparing Viread with stavudine (another antiviral medicine), taken in combination with lamivudine and efavirenz (other antiviral medicines). A fourth study in 90 adolescents (12 to 18 years of age) compared the effects of adding Viread with those of adding placebo to existing treatment. All studies looked at the levels of HIV in the blood as the main measure of effectiveness.

For the treatment of hepatitis B, the effectiveness of Viread was compared with that of adefovir dipivoxil (another antiviral medicine) in two studies. The first study involved 382 ‘HBeAg-negative’ patients (infected with a virus that has mutated [changed], leading to a form of hepatitis B that is more difficult to treat), and the second involved 272 ‘HBeAg-positive’ patients (infected with the common type of the hepatitis B virus). Both studies looked at the number of patients who had responded completely to treatment after 48 weeks, as determined by level of virus in the blood being below 400 copies/ml and a reduction in liver damage as seen using a biopsy (when a sample of liver tissue is taken and viewed under the microscope). A third study involved 112 hepatitis B patients whose liver had stopped working properly. The patients were given Viread alone, entecavir (another hepatitis medicine) or Viread with emtricitabine (another antiviral medicine). Although this study looked mainly at the safety of the medicine, it also looked at measures of effectiveness such as the number of patients with a blood virus level below 400 copies/ml after 48 weeks. Viread

What benefits has it shown during the studies?

In HIV-infected adults, Viread, taken in combination with other antiviral medicines, caused a reduction in viral load (the amount of virus found in the blood). In the two studies of treatment-experienced patients, adding Viread resulted in a fall in viral load of around 75% after four and after 24 weeks, compared with a small rise or fall in viral load of around 5% in the patients taking placebo. In treatment-naïve patients, Viread was as effective as stavudine, with similar numbers of patients in the Viread and stavudine groups having viral loads below 400 copies/ml after 48 weeks. In the study in adolescents, after 48 weeks, there was no benefit of adding Viread to existing treatment compared with adding placebo.

In patients with hepatitis B, Viread was more effective than adefovir dipivoxil. After 48 weeks, 71% of the HBeAg-negative and 67% of the HBeAg-positive patients taking Viread had a complete response, compared with 49% and 12%, respectively, of the patients taking adefovir dipivoxil. In the third study, around 70% of patients taking Viread or entecavir had a viral level below 400 copies/ml. The figure for the combination treatment with Viread with emtricitabine was 88%.

What is the risk associated?

The most common side effects with Viread (seen in more than 1 patient in 10) are nausea (feeling sick), vomiting, diarrhoea, dizziness, hypophosphataemia (low levels of phosphate in the blood), rash and asthenia (weakness). For the full list of side effects reported with Viread, see the package leaflet.

Viread should not be used in people who may be hypersensitive (allergic) to tenofovir, to tenofovir disoproxil fumarate, or to any of the other ingredients.

Why has it been approved?

The CHMP decided that Viread’s benefits are greater than its risks and recommended that it be given marketing authorisation.

Further information

The European Commission granted a marketing authorisation valid throughout the European Union for Viread to Gilead Sciences International Limited on 5 February 2002. After five years, the marketing authorisation was renewed for a further five years. europa.eu/Find medicine/Human medicines/European Public Assessment Reports. For more information about treatment with Viread, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.

This summary was last updated in 03-2011. Viread