1 Indian Journal of Pharmaceutical Sciences January - February 2006 www.ijpsonline.com Review Review Review Review Review Article Article Article Article Article Antiretrovirals: Need for an Effective Drug Delivery Antiretrovirals: Need for an Effective Drug Delivery Antiretrovirals: Need for an Effective Drug Delivery Antiretrovirals: Need for an Effective Drug Delivery Antiretrovirals: Need for an Effective Drug Delivery KUSUM V. DEVI* AND ROOPA S. PAI Al–Ameen College of Pharmacy, Near Lal–Bagh Main Gate, Hosur Road, Bangalore-560 027, India. Human Immunodeficiency Virus (HIV) is a retrovirus that causes irreversible destruction of the immune system, leading to the occurrence of opportunistic infections and malignancies. During the last decade, even though attempts were being made to eradicate H IV, it was found that eradication of H IV is highly unlikely, and effective antiretroviral therapy is required on a long-term basis to maintain viral suppression and reduce disease progression. During this decade, effective therapies aimed at continued suppression of H IV replication and targeted at resting H IV reservoirs such as brain, lymphatic systems will be critical to prolong survival and renewing hopes for a cure. Currently available antiH IV drugs can be classified into three categories: nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors and protease inhibitors. Most of these drugs bear some significant drawbacks such as relatively short half-life, low bioavailability, poor permeability and undesirable side effects. Efforts have been made to design drug delivery systems for antiH IV agents to: a) reduce the dosing frequency, b) increase the bioavailability and decrease the degradation/ metabolism in the gastrointestinal tract, c) improve the CNS penetration and inhibit the CNS efflux, and d) deliver them to the target cells selectively with minimal side effects. T his article is an attempt to compile all major research work towards drug delivery for AIDS therapy and channel future attempts in the area of more effective controlled delivery of antiHIV agents. Human Immunodeficiency Virus (HIV) is a retrovirus that can be subdivided into HIV-1 and HIV-2. Both types of HIV infection depletes the helper T-lymphocytes (CD4 cell/mm 3 ), resulting in continued destruction of the immune system, leading to the occurrence of opportunistic infections and malignancies. A person infected with HIV is defined by Centers for Disease Control and Prevention (CDC) as having positive antibodies against HIV (positive HIV test), with 200 or more helper T-lymphocytes, and the absence of an Acquired Immunodeficiency Syndrome (AIDS) defining illness. By definition then, an HIV infected person with AIDS has fewer than 200 cells/mm 3 CD4 cells or the presence of AIDS defining illness. During the last decade, though attempts were being made to eradicate HIV, it was found that eradication of HIV is highly unlikely, and effective antiretroviral therapy is required on a long-term basis to maintain viral suppression and reduce disease progression. During this decade, effective therapies aimed at continued suppression of HIV replication and targeted at resting HIV reservoirs such as brain, lymphatic systems will be critical to prolong survival and renewing hopes for a cure. Thus goals of antiretroviral therapy include, reducing the symptoms of HIV infection and delay disease progression to AIDS, reducing viral load to undetectable levels or lowest level possible for sufficiently longer duration, maintenance of durability of viral suppression, eliminating resting reservoirs of HIV, reducing viral resistance and drug failure, designing effective therapeutic regimens that minimize the drug adherence problem, reducing total pill burden and minimizing interference with quality life. Diagnosis and commencement of treatment: Established HIV infection is diagnosed by finding antibodies to HIV in the plasma using various serological testing methods such as ELISA (Enzyme Linked Immuno Sorbent Assays), Orasure western blot, SUDS (Single Used Diagnostic System), Orasure HIV-1. Generally according to the United States Food and Drug Administration and World Health Organization guidelines, the antiretroviral therapy is commenced with these observations, such as when patients experience severe symptoms of HIV infection or have been diagnosed with AIDS or when the viral load in the blood sample is found to be 50,000 copies/ml or more or when the CD4 cell count is less than 200-350 cells/mm 3 . *For correspondence E-mail: kusumal62@yahoo.com