Therapy of HIV is complicated by the fact that the HIV genome is incorporated into the host cell genome and can remain there in a dormant state for prolonged periods until it is reactivated. Effective therapy must be directed against both free virus and virus-infected cells. Although a number of substances with in vitro anti-HIV activity have been described, only a few drugs exhibit anti-HIV activity in vivo at tolerable toxicities. The main group of substances described are;
1. Nucleoside analogues reverse transcriptase inhibitors. AZT, DDC, DDI and lamuvidine.
2. Non-nucleoside analogue reverse transcriptase inhibitors e.g. Nevirapine
3. HIV Protease inhibitors e.g. Ritonavir, Indivavir. They are the most potent inhibitors of HIV replication to date.
Zidovudine (AZT) was the first anti-viral agent shown to have beneficial effect against HIV infection. However, after prolonged use, AZT-resistant strains rapidly appears which limits the effect of AZT. Recent clinical trials reported significant benefit in the use of combination therapy over the use of monotherapy. The rationale for this approach is that by combining drugs that are synergistic, non-cross-resistant and no overlapping toxicity, it may be possible to reduce toxicity, improve efficacy and prevent resistance from arising. In fact, significant success has now been reported for trials involving multiple agents including protease inhibitors. The aim of anti-HIV therapy has now shifted from simply delaying the progression of disease to finding a permanent cure. We have now entered the era of highly active anti-retroviral therapy (HAART).
The current consensus is that one should give a potent combination of agents HAART right from the start when treatment is indicated. The most popular combination is AZT and lamivudine plus a protease inhibitor. Lamivudine has greater anti-retroviral activity that AZT alone and is active against many AZT-resistant strains without significant increase in toxicity.. Among protease inhibitors, indinavir (IDV) is more potent than saquinavir and appears to have fewer drug interactions and short-term adverse effects than ritonavir. In currently recommended doses, AZT prophylaxis is well-tolerated with health workers; short-term toxicity associated with higher doses primarily includes GI symptoms, fatigue, and headache. In HIV-infected adults, 3TC can cause GI symptoms, and rarely pancreatitis. IDV toxicity includes GI symptoms and after prolonged use, mild hyperbilirubinaemia (10%), and kidney stones (4%).Below is a table of some of the drugs available.
| Diagnostic Tests | Prognostic Tests | Antiviral Susceptibility Tests | Treatment |
| 3 Types of Inhibitor | Monitoring anti-HIV therapy | Prevention |
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