Abstract:
The majority of anti-HIV drug susceptibility tests have been performed on subtype B HIV-1 strains, since these are the most prevalent in countries
designing, testing, and manufacturing the current anti-HIV agents. The increasing global spread of HIV subtype highlights the need to determine
the activity of anti-HIV drugs against subtypes of HIV other than subtype B. Furthermore an increasing number of individuals infected with many of
the non subtype B virus strains now receive antiretroviral therapy because of rollout programs in developing countries as well as increasing
migration to the developed world. The phenotypic susceptibility of two laboratory strains HIV-1JFRL and HIV-1IIIB (representing subtype B) and
two clinical isolates HIV-104RTA and HIV-1025RTA (representing subtypes A and D respectively) was determined. The in vitro drug susceptibility testing
of the isolates was carried out in C8166 cell line and in peripheral blood mononuclear cells (PBMCs). The study revealed that the drugs used in the
Kenyan national ART program inhibited HIV-1 replication in-vitro as their inhibitory concentrations (IC50) compared well with the standard
Inhibitory concentration values. The results also suggest a biochemical similarity of the reverse transcriptase (RT) and protease enzymes from
these subtypes despite the divergence at the genetic level. The findings suggest that similar clinical benefits of antiviral therapy obtain in persons
infected with other subtypes of HIV-1other than subtype B and that the generic drugs used in the national ART program in Kenya are as
efficacious as branded drugs in inhibiting HIV replication in vitro despite the limited number of the viruses studied.
