Global campaigns towards local manufacture of anti-HIV/AIDS drugs in continuous flow systems

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INTRODUCTION
Approximately 41 years ago, in Los Angeles California, between the period of October 1980 and May 1981, five young previously healthy gay men were treated for pneumocystis carinii and were reported to all have had laboratory-confirmed previous and current cytomegalovirus infection and candida mucosal infections at the time. According to the symptoms that the patients presented, health experts suggested a possibility of a cellular-immune dysfunction related to a common exposure that predisposes individuals to opportunistic infections such as these (1). This cellular-immune dysfunction later came to be known as Acquired Immunodeficiency Syndrome (AIDS) caused by the Human Immunodeficiency Virus (HIV) of the family Lentiviridae. By 1985, clinical trials were underway for azidothymidine (AZT) (2) and in 1987, the US Food and Drug Administration approved AZT, a nucleoside reverse transcriptase inhibitor (NRTI), for anti-retroviral treatment of HIV/AIDS (3, 4). Unfortunately, it was found that a combination of drugs was needed for treatment of HIV/AIDS (5). This gave rise to a two-NRTI drug therapy comprising of AZT and zalcitabine or dideoxycytidine (ddC), which was later followed by a triple drug therapy (AZT, ddC and Saquinavir) in 1996. This is also known as highly active antiretroviral treatment (HAART). The latter enabled durable suppression of HIV replication to minimal levels and additionally created a high genetic barrier against development of drug resistance (6). Massive strides have been made with regard to the treatment of HIV/AIDS over the years. Currently, the anti-retroviral classes of drugs used in HIV/AIDS treatment include reverse transcriptase inhibitors, protease inhibitors, integrase-strand transfer inhibitors, fusion inhibitors, CCR5 antagonists, pharmacokinetic enhancers, attachment inhibitors and post-attachment inhibitors (7). It is also notable that triple combination therapy has been reported to be effective thus far (8, 9).