The European Commission granted approval of a new tablet formulation of Abbott's antiretroviral medication Norvir® (ritonavir) on Jan. 25, 2010. The new Norvir tablets can be stored at room temperature and do not require refrigeration, making it more convenient for some patients. European approval is a critical step in Abbott's efforts to expedite registration filings for the Norvir tablet in countries around the world, including in developing countries where the majority of people with HIV live. The Norvir tablets and the Norvir soft-gelatin capsules both contain 100 mg of ritonavir. While the rate of drug absorbed is different, there is no requirement for dosage change. The Norvir tablet is the direct result of years of effort by Abbott scientists who wanted to improve this critical component of HIV treatment by making it more convenient for patients. The tablet was developed using Abbott's Meltrex® technology, a proprietary melt-extrusion process that makes it more heat-stable. This is the same technology used to develop Abbott's Kaletra® tablet, which combines lopinavir and ritonavir. Norvir is used in combination with other antiretroviral medications to treat HIV
Use and Important Safety Information1
Norvir (ritonavir) is indicated in combination with other antiretroviral (anti-HIV) medicines for the treatment of HIV-1 infected adults and children 2 years of age and older.
Important Safety Information
Norvir should not be given to people who are allergic (hypersensitive) to ritonavir or any of the other ingredients in Norvir.
When Norvir is used as a pharmacokinetic enhancer of other protease inhibitors (PIs), the Summary of Product Characteristics (SPC) of the co-administered antiretroviral (anti-HIV) medicines should be consulted for full details on the Important Safety Information of each product
The below list of drug interactions is not complete. Before taking Norvir, people must tell their doctor about all the medicines they are taking or are planning to take. These include other prescription and non-prescription medicines and herbal supplements.
Norvir should not be taken with the following medicines due to the potential for serious and/or life-threatening reactions: alfuzosin, amiodarone, astemizole, bepridil, cisapride, clorazepate, clozapine, diazepam, dihydroergotamine, encainide, ergonovine, ergotamine, estazolam, flecanide, flurazepam, fusidic acid, lovastatin, methylergonovine, oral midazolam, pethidine, pimozide, piroxicam, propafenone, propoxyphene, quinidine, rifabutin, sildenafil when used for treating pulmonary arterial hypertension, simvastatin, St. John's Wort (hypericum perforatum), terfenadine, triazolam and vorconizole.
Particular caution should be exercised in people taking the following medicinal products with Norvir: PDE5 inhibitors (sildenafil, tadalafil, vardenafil) when used for the treatment of erectile dysfunction, atazanavir, digoxin, ethinyl estradiol, fosamprenavir, HMG-CoA reductase inhibitors (atorvastatin, rosuvastatin), glucocorticoids, tipranavir, trazadone, and rifampicin and saquinavir taken together with Norvir.
Women taking oral contraceptives ("the pill") or the contraceptive patch to prevent pregnancy, should use a different type of contraception since Norvir may reduce the effectiveness of oral or patch contraceptives.
Norvir oral solution contains alcohol. People should talk with their doctor if they are taking or planning to take disulfiram (a medicine used to treat alcoholism) or metronidazole (a medicine used for certain infections) as severe nausea and vomiting can occur.
Special warnings and precautions for use
Norvir is not a cure for HIV-1 infection or AIDS and does not prevent the risk of transmission of HIV to others. People taking Norvir may still develop infections or other illnesses associated with HIV infection or AIDS.
Norvir should not be given to people with severe liver disease. People with chronic hepatitis B or C that are being treated with a combination of antiretroviral medicines for HIV are at a greater risk for severe and potentially fatal reactions because of the effect on the liver. People should tell their healthcare provider if they have any of the following symptoms: loss of appetite, yellowing of skin or eyes (jaundice), dark colored urine, pale colored stools, itchy skin and/or stomach area (abdominal) pain.
Pancreas problems (pancreatitis) which may cause serious problems have been reported in some people taking Norvir. People should tell their doctor if they have nausea, vomiting or stomach pain as these may be signs of pancreatitis.
People should tell their healthcare provided if they have diarrheoa or vomiting that is not improving (persistent) as this may reduce how well medicines are working.
Diabetes and high blood sugar (hyperglycemia), change in body fat (lipodystrophy), and increased bleeding in people with hemophilia have occurred in some people taking protease inhibitors such as Norvir. The cause and long-term effects of body fat changes are not known at this time.
Some people with advance HIV infection (AIDS) who then start anti-HIV treatment may develop the symptoms of infections they have had in the past even if they did not know they had had them.
Joint stiffness, aches and pains may be a sign of a problem that can destroy bone (osteonecrosis). Some people taking a number of antiretroviral (anti-HIV) medicines may develop this disease.
There have been reports of serious muscle disorders, particularly when taking medicines to lower cholesterol in combination with antiretroviral therapy including protease inhibitors and nucleoside analogues. People should tell their healthcare provider if they have unexplained muscle pain, tenderness or weakness.
Changes in the electrocardiogram (EKG) can occur when taking Norvir. People should consult their physician if they experience dizziness, lightheadedness, fainting spells or abnormal heart beat. People with heart defects or conduction defects should avoid Norvir.
Very common side effects of Norvir are stomach ache, vomiting, diarrheoa, feeling sick, headache, a tingling sensation or numbness in the hands, feet or around the lips or mouth, feeling weak/tired, and a bad taste in the mouth.
References: 1. Norvir [Summary of Product Characteristics]. Queenborough, United Kingdom. Abbott Laboratories Limited, 2010