Heptavir

Heptavir is an antiviral drug with a direct type of therapeutic activity. It belongs to the group of nucleoside-type drugs that slow down the action of reverse transcriptase.

Once inside the cell, lamivudine undergoes phosphorylation to form the active 5-3-phosphate metabolic element, lamivudine-3-phosphate, which is a substrate for hepatitis B polymerase; this component slows down the activity of HIV reverse transcriptase. Lamivudine-3-phosphate does not affect normal cellular DNA metabolism processes. [ 1 ]

Indications Heptavir

It is used in combination therapy with other antiretroviral agents in people with HIV infection.

Release form

The drug is released in tablet form - 10 pieces inside blister packs; a box contains 10 such packs.

Pharmacokinetics

Lamivudine is well absorbed in the digestive system; after oral administration, bioavailability values in adults are 80-85%. Protein synthesis rate is 36%. Serum Cmax is observed after 60 minutes. In the case of administration of therapeutic doses, it is approximately 1.1-1.5 μg/ml; minimum values are 0.015-0.02 μg/ml.

Distribution volume level – 1.3±0.4 l/kg.

Taking lamivudine with food prolongs the period required to achieve Cmax and its values (up to 47%), but does not change the total value of the absorbed element, which allows the drug to be taken with food.

The average values of total clearance of lamivudine are 0.3 l/hour/kg. The half-life is in the range of 5-7 hours. The substance is excreted in urine mostly unchanged – through active excretion and CF. Intrarenal clearance rates are about 70% of excreted lamivudine.

Dosing and administration

Adults should take 0.15 g of the drug orally twice a day. Treatment is carried out in combination with other antiretroviral agents.

In the case of Heptavir therapy in people infected with two viruses at once – HBV and HIV – the dose recommended for HIV treatment should be used as part of the selected regimen of complex therapy.

• Application for children

For a child weighing less than 40 kg, other forms of this medication should be used.

Contraindications

It is contraindicated to prescribe the medication to people with diagnosed clinical intolerance to the components of the drug.

Women infected with HIV are prohibited from breastfeeding because it can lead to infection of the baby.

Side effects Heptavir

Side effects include:

• problems with digestive function: diarrhea, discomfort and pain in the epigastric region, vomiting, loss or weakening of appetite, nausea, and also pancreatitis and an increase in plasma amylase levels or intrahepatic transaminase activity;
• disorders of hematopoiesis: thrombocyto- or neutropenia, as well as anemia;
• disorders associated with the central nervous system: headaches, polyneuropathy, fatigue and paresthesia;
• Others: fever, alopecia and respiratory tract infections.

Overdose

A sign of drug poisoning is the potentiation of side effects.

Gastric lavage, forced diuresis and administration of activated carbon are performed. In addition, symptomatic actions are performed.

Interactions with other drugs

Combined use of the drug with interferon leads to a slight decrease in the AUC of lamivudine (by 10%); the pharmacokinetics of interferon remain unchanged. No interactions between the indicated drugs are registered.

Combining Heptavir with sulfonamides, didanosine or zalcitabine increases the risk of pancreatitis.

Administration with myelosuppressive (sulfonamides, amphotericin with ganciclovir, flucytocin trimetrexate, and pyrimethamine with dapsone) or cytotoxic agents may provoke the development of hematotoxicity.

Combination with drugs that have nephrotoxic activity (aminoglycosides, pentamidine with amphotericin and foscarnet with cidofovir) increases the values of lamivudine.

Use with didanosine, zalcitabine, and also with isoniazid, dapsone and stavudine increases the likelihood of developing polyneuropathy.

Storage conditions

Heptavir should be stored in a place inaccessible to small children. Temperature level – in the range of 15-30°C.

Shelf life

Heptavir can be used within a 2-year period from the date of manufacture of the therapeutic product.

Analogues

Analogues of the drug are Sebivo, Baraclude and Stag with Zeffix, and in addition Retrovir, Viread with Tenofovir-tl, Azidothymin and Ziagen with Emtricitabine.