HIVID
HIVID - General Information
A dideoxynucleoside compound in which the 3&
Pharmacology of HIVID
HIVID inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA.
HIVID for patients
Although Zalcitabine is an Anti-HIV Agent, it doesn't cure HIV infection. Patients can still transmit HIV to others through sexual contact or blood contamination.
Patients should not change the dose or stop Zalcitabine without discussing with their doctors. Zalcitabine may cause peripheral neuopathy, pancreatitis, hepatic toxicity and other toxicities. If patients experience any unusual symptoms or signs, they should contact their doctors immediately.
HIVID Interactions
Zidovudine: There is no significant pharmacokinetic interaction between ZDV and zalcitabine which has been confirmed clinically. Zalcitabine also has no significant effect on the intracellular phosphorylation of ZDV, as shown in vitro in peripheral blood mononuclear cells or in two other cell lines (U937 and Molt-4). In the same study it was shown that didanosine and stavudine had no significant effect on the intracellular phosphorylation of zalcitabine in peripheral blood mononuclear cells.
Lamivudine: In vitro studies in peripheral blood mononuclear cells, U937 and Molt-4 cells revealed that lamivudine significantly inhibited zalcitabine phosphorylation in a dose dependent manner. Effects were already seen with doses corresponding to relevant plasma levels in humans, and the intracellular phosphorylation of zalcitabine to its three metabolites (including the active zalcitabine triphosphate metabolite) was significantly inhibited. Zalcitabine inhibited lamivudine phosphorylation at high concentration ratios (10 and 100); however, it is considered to be unlikely that this decrease of phosphorylated lamivudine concentration is of clinical significance, as lamivudine is a more efficient substrate for deoxycytidine kinase than zalcitabine. These in vitro studies suggest that concomitant administration of zalcitabine and lamivudine in humans may result in sub-therapeutic concentrations of active phosphorylated zalcitabine, which may lead to a decreased antiretroviral effect of zalcitabine. It is unknown how the effect seen in these in vitro studies translates into clinical consequences. Concomitant use of zalcitabine and lamivudine is not recommended.
Saquinavir: The combination of HIVID, saquinavir, and ZDV has been studied (as triple combination) in adults. Pharmacokinetic data suggest that absorption, metabolism, and elimination of each of these drugs are unchanged when they are used together.
Drugs Associated With Peripheral Neuropathy: The concomitant use of HIVID with drugs that have the potential to cause peripheral neuropathy should be avoided where possible. Drugs that have been associated with peripheral neuropathy include antiretroviral nucleoside analogues, chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, and vincristine. Concomitant use of HIVID with didanosine is not recommended.
Intravenous Pentamidine: Treatment with HIVID should be interrupted when the use of a drug that has the potential to cause pancreatitis is required. Death due to fulminant pancreatitis possibly related to intravenous pentamidine and HIVID has been reported. If intravenous pentamidine is required to treat Pneumocystis carinii pneumonia, treatment with HIVID should be interrupted.
Amphotericin, Foscarnet, and Aminoglycosides: Drugs such as amphotericin, foscarnet, and aminoglycosides may increase the risk of developing peripheral neuropathy or other HIVID-associated adverse events by interfering with the renal clearance of zalcitabine (thereby raising systemic exposure). Patients who require the use of one of these drugs with HIVID should have frequent clinical and laboratory monitoring with dosage adjustment for any significant change in renal function.
Probenecid or Cimetidine: Concomitant administration of probenecid or cimetidine decreases the elimination of zalcitabine, most likely by inhibition of renal tubular secretion of zalcitabine. Patients receiving these drugs in combination with zalcitabine should be monitored for signs of toxicity and the dose of zalcitabine reduced if warranted.
Magnesium/Aluminum-containing Antacid Products: Absorption of zalcitabine is moderately reduced (approximately 25%) when coadministered with magnesium/aluminum-containing antacid products. The clinical significance of this reduction is not known, hence zalcitabine is not recommended to be ingested simultaneously with magnesium/aluminum-containing antacids.
Metoclopramide: Bioavailability is mildly reduced (approximately 10%) when zalcitabine and metoclopramide are coadministered.
Doxorubicin: Doxorubicin caused a decrease in zalcitabine phosphorylation (>50% inhibition of total phosphate formation) in U937/Molt 4 cells. Although there may be decreased zalcitabine activity because of lessened active metabolite formation, the clinical relevance of these in vitro results are not known.
HIVID Contraindications
HIVID is contraindicated in patients with clinically significant hypersensitivity to zalcitabine or to any of the excipients contained in the tablets.
Additional information about HIVID
HIVID Indication: For the treatment of Human immunovirus (HIV) infections.
Mechanism Of Action: HIVID is a nucleoside reverse transcriptase inhibitor (NRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). HIVID is phosphorylated to active metabolites that compete for incorporation into viral DNA. They inhibit the HIV reverse transcriptase enzyme competitively and act as a chain terminator of DNA synthesis. The lack of a 3'-OH group in the incorporated nucleoside analogue prevents the formation of the 5' to 3' phosphodiester linkage essential for DNA chain elongation, and therefore, the viral DNA growth is terminated.
Drug Interactions: Not Available
Food Interactions: Take on empty stomach: 1 hour before or 2 hours after meals.
Do not take calcium, aluminium, magnesium or iron supplements within 2 hours of taking this medication.
Generic Name: Zalcitabine
Synonyms: Dideoxycytidine; DDC; DDCYD
Drug Category: Anti-HIV Agents; Antimetabolites; Nucleoside and Nucleotide Reverse Transcriptase Inhibitors
Drug Type: Small Molecule; Approved
Other Brand Names containing Zalcitabine: HIVID;
Absorption: Bioavailability is over 80% following oral administration.
Toxicity (Overdose): Acute overdose: Inadvertent pediatric overdoses have occurred with doses up to 1.5 mg/kg zalcitabine. Chronic overdose: in an initial dose-finding study in which zalcitabine was administered at doses 25 times (0.25 mg/kg every 8 hours) the currently recommended dose, one patient discontinued zalcitabine after 1½ weeks of treatment subsequent to the development of a rash and fever.
Protein Binding: Less than 4%
Biotransformation: Hepatic
Half Life: 2 hours
Dosage Forms of HIVID: Tablet, film coated Oral
Chemical IUPAC Name: 4-amino-1-[(2R,5S)-5-(hydroxymethyl)oxolan-2-yl]pyrimidin-2-one
Chemical Formula: C9H13N3O3
Zalcitabine on Wikipedia: https://en.wikipedia.org/wiki/Zalcitabine
Organisms Affected: Human Immunodeficiency Virus