Active Substance: saquinavir
Common Name: saquinavir
ATC Code: J05AE01
Marketing Authorisation Holder: Roche Registration Limited
Active Substance: saquinavir
Authorisation Date: 1996-10-04
Therapeutic Area: HIV Infections
Pharmacotherapeutic Group: Antivirals for systemic use
Invirase is indicated for the treatment of HIV-1-infected adult patients. Invirase should only be given in combination with ritonavir and other antiretroviral medicinal products.
What is Invirase?
Invirase is a medicine containing the active substance saquinavir. It is available as capsules (200 mg) and tablets (500 mg).
What is Invirase used for?
Invirase is used to treat adults infected with the human immunodeficiency virus type 1 (HIV‑1), a virus that causes acquired immune deficiency syndrome (AIDS). Invirase should only be used in combination with ritonavir (another antiviral medicine) and other antiviral medicines.
The medicine can only be obtained with a prescription.
How is Invirase used?
Treatment with Invirase should be started by a doctor who has experience in the treatment of HIV infection.
For patients who were previously taking antiviral agents the recommended dose of Invirase is 1,000 mg with 100 mg ritonavir twice a day. For patients who were not previously taking antiviral agents, Invirase should be started at 500 mg two times daily with ritonavir 100 mg two times daily for the first 7 days of treatment. After 7 days, the recommended dose of Invirase is 1,000 mg two times daily with ritonavir 100 mg two times daily in combination with other antiretroviral agents.
How does Invirase work?
The active substance in Invirase, saquinavir, is a ‘protease inhibitor’. It blocks an enzyme called protease, which is involved in the reproduction of HIV. When the enzyme is blocked, the virus does not reproduce normally, slowing down the spread of infection. Ritonavir is another protease inhibitor that is used as a ‘booster’. It slows down the rate at which saquinavir is broken down, increasing the levels of saquinavir in the blood. This allows a lower dose of saquinavir to be used for the same antiviral effect. Invirase, taken in combination with other antiviral medicines, reduces the amount of HIV in the blood and keeps it at a low level. Invirase 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.
How has Invirase been studied?
Invirase was assessed in six main studies involving a total of 1,576 patients. The first four studies assessed the medicine’s effects without ritonavir. The combination of Invirase with ritonavir was assessed in 656 patients in two studies that compared Invirase with indinavir and with lopinavir (other antiviral medicines), both in combination with ritonavir and other antiviral medicines. These studies measured the viral load (the level of HIV in the patient’s blood) after 48 weeks.
What benefit has Invirase shown during the studies?
Invirase, taken in combination with other antiviral medicines, resulted in a reduction of the viral loads and improvements in the immune system. In the studies of Invirase in combination with ritonavir, Invirase was as effective as indinavir, but more effective than lopinavir in reducing the viral load to less than 50 copies/ml. This was mainly caused by more patients stopping Invirase treatment rather than by any differences in the effectiveness of the medicines.
What is the risk associated with Invirase?
The most common side effects when taking Invirase in combination with ritonavir (seen in more than 1 patient in 10) are diarrhoea, nausea (feeling sick), increased levels of liver enzymes, cholesterol and triglycerides (a type of fat) in the blood, and decreased levels of platelets in the blood (components that help blood to clot). For the full list of all side effects reported with Invirase, see the package leaflet.
Invirase must not be used in patients who have severe problems with their liver, QT prolongation (an alteration of the electrical activity of the heart), altered levels of electrolytes in the blood (especially low potassium levels), bradycardia (slow heart rate) or heart failure (when the heart does not work as well as it should). It must not be used in patients who have had arrhythmia (unstable heartbeat) in the past. It must also not be used in patients who are taking any of the following medicines, which could cause harmful side effects if taken with Invirase:
- medicines that could cause QT prolongation or PR prolongation (another type of heart activity alteration);
- midazolam taken by mouth, triazolam (used to relieve anxiety or difficulty sleeping);
- simvastatin, lovastatin (used to lower cholesterol);
- ergot alkaloids, such as ergotamine, dihydroergotamine, ergonovine and methylergonovine (used to treat migraine headache);
- rifampicin (used to treat tuberculosis);
- quetiapine (used to treat depression).
Caution is needed when Invirase is taken at the same time as some other medicines. See the package leaflet for full details.
Why has Invirase been approved?
The CHMP decided that Invirase’s benefits are greater than its risks and recommended that it be given marketing authorisation.
What measures are being taken to ensure the safe and effective use of Invirase?
A risk management plan has been developed to ensure that Invirase is used as safely as possible. Based on this plan, safety information has been included in the summary of product characteristics and the package leaflet for Invirase, including the appropriate precautions to be followed by healthcare professionals and patients.
Other information about Invirase
The European Commission granted a marketing authorisation valid throughout the European Union for Invirase on 4 October 1996.
For more information about treatment with Invirase, read the package leaflet (also part of the EPAR) or contact your doctor or pharmacist.