Зальцитабин

Описание

Zalcitabine is an orally active dideoxynucleoside andog for combination use with zidovudine in advanced HIV infection and also as monotherapy for AIDS patients who cannot tolerate or have not responded to zidovudine. It has a similar mechanism of action (inhibition of reverse transcriptase) to didanosine. Like didanosine, its side effect profile includes peripheral neuropathy. Unlike zidovudine, zalcitabine does not cause bone marrow suppression.

Химические свойства

White to Off-White Cyrstalline Powder

Показания

Zalcitabine (ddC, Hivid) is a cytidine analogue active against HIV-1, HIV-2, and hepatitis B virus. It is used for the treatment of HIV infection in adults and asymptomatic children as part of a multidrug regimen. It may be less effective than the other nucleoside inhibitors and is used less frequently.

Определение

ChEBI: A pyrimidine 2',3'-dideoxyribonucleoside compound having cytosine as the nucleobase.

Общее описание

Zalcitabine, 2',3'-dideoxycytidine or ddCyd, is an analog ofcytosine that demonstrates activity against HIV-1 and HIV-2,including strains resistant to AZT. The potency (in peripheralblood mononuclear cells) is similar to that of AZT, but thedrug is more active in populations of monocytes andmacrophages as well as in resting cells.
The oral bioavailability of zalcitabine is over 80% in adultsand less in children.The major dose-limiting side effect isperipheral neuropathy, characterized by pain, paresthesias,and hypesthesia, beginning in the distal lower extremities.These side effects are typically evident after several months oftherapy with zalcitabine. A potentially fatal pancreatitis is anothertoxic effect of treatment with ddC. The drug has beenapproved for the treatment of HIV infection in adults with advanceddisease who are intolerant to AZT or who have diseaseprogression while receiving AZT. ddC is combined with AZTfor the treatment of advanced HIV infection.

Реакции воздуха и воды

Water soluble.

Профиль реактивности

Zalcitabine may be sensitive to prolonged exposure to light.

Пожароопасность

Flash point data for Zalcitabine are not available; however, Zalcitabine is probably combustible.

Фармаколо?гия

Peripheral neuropathy occurs in up to 50% of patients taking zalcitabine. Stomatitis, esophageal ulceration, hepatotoxicity, rash, and pancreatitis may occur. Zalcitabine should be used with caution in individuals with a history of pancreatitis, liver disease, or alcohol abuse. Dosage adjustment is necessary for individuals with renal impairment. Zalcitabine should not be used in combination with didanosine, lamivudine, or stavudine.

Фармакокине?тика

Zalcitabine (ddC) is a useful alternate drug to ZDV and is given in combination with ZDV when CD4 cell counts fall to less than 300 cells/mm3 . Monotherapy with ddC is more active than ZDV. Its oral bioavailability is 87%, and its plasma half-life is approximately 1 hour. In low doses (0.005 mg/kg every 4 hours), ddC produces sustained decrease in p24 antigen level and increase in CD4 cell counts. The CSF fluid/plasma ratio of ddC is 0.2. Following oral administration, bioavailability of ddC is less than 80%, which is further reduced when taken with food. The mean maximum plasma concentration of the drug also is reduced from 25.2 to 15.5 ng/mL when the drug was taken with food.

Побочные эффекты

It has side effects, such as stomatitis, rash, fever, malaise, arthritis, and arthralgia.

Метаболизм

Dideoxyuridine is the major metabolite in urine and feces. The drug penetrates the blood-brain barrier. The major toxicity of ddC is peripheral neuropathy, in which case it should be discontinued. In some cases, pancreatitis occurs when given alone or in combination with ZDV."