Alternating and intermittent regimens of zidovudine (3'-azido-3'-deoxythymidine) and dideoxycytidine (2',3'-dideoxycytidine) in the treatment of patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex
Article Abstract:
Research is continuing into medications that may counteract infection with the human immunodeficiency virus (HIV), which causes AIDS. It is known that HIV can be suppressed by agents that inhibit the viral enzyme known as reverse transcriptase, which is essential for the replication, or production, of HIV. One of the first reverse transcriptase inhibitors, zidovudine (AZT), was shown to suppress HIV infection and prolong the survival of patients with AIDS or AIDS-related complex (ARC). However, AZT causes myelosuppression (inhibition of bone marrow function) and its widespread use has also resulted in the development of AZT-resistant viral strains. A more recently developed antiviral agent, 2',3'-dideoxycytidine (ddC), was shown to be a powerful inhibitor of reverse transcriptase, but caused severe and painful peripheral neuropathy, disease of the peripheral nervous system. The combination of AZT and ddC in alternate dosing regimens may reduce the toxicities associated with each drug while retaining the antiviral activity of each agent. Alternate dosing regimens consist of therapy with one antiviral agent for a specific period of time followed by the administration of the other antiviral agent for a specific duration. Two hundred milligrams (mg) of AZT given orally every four hours for either a week or a month is alternated with oral doses of 0.01 or 0.03 mg ddC per kilogram (kg) body weight every four hours for weekly or monthly periods. A weekly intermittent regimen consisting of 200 mg AZT and 0.03 mg per kg ddC is also being tested. The rationale and methodology of these clinical trials are described. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: American Journal of Medicine
Subject: Health care industry
ISSN: 0002-9343
Year: 1990
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Salvage therapy for zidovudine-intolerant HIV-infected patients with alternating and intermittent regimens of zidovudine and dideoxycytidine
Article Abstract:
The drug zidovudine (AZT) suppresses the replication of the human immunodeficiency virus (HIV) in the body. In this way it can prolong the survival of patients with AIDS or AIDS-related complex (ARC). However, AZT causes the side effect of myelosuppression (inhibition of bone marrow function) and for this reason the dose must be limited in some patients. A more recently developed antiviral agent, 2',3'-dideoxycytidine (ddC), is effective against HIV but causes severe and painful peripheral neuropathy, or disease of the peripheral nervous system. The side effects of AZT and ddC both become worse with increasing drug dose, and subside after interruption or discontinuation of the drug. Intermittent or interrupted dose regimens provide rest periods for recovery from drug toxicity, thereby increasing the patient's tolerance to these agents. An intermittent regimen may serve as a salvage therapy for patients who cannot tolerate continuous doses of AZT. Another approach is to provide continuous anti-HIV therapy by alternating AZT with ddC, which have different side effects. The antiviral activity and safety of weekly intermittent, weekly alternating, and monthly alternating regimens of AZT and ddC are currently under investigation. (Consumer Summary produced by Reliance Medical Information, Inc.)
Publication Name: American Journal of Medicine
Subject: Health care industry
ISSN: 0002-9343
Year: 1990
User Contributions:
Comment about this article or add new information about this topic: