Abacavir + Lamivudine + Zidovudine

Trizivir is indicated for the treatment of human-immunodeficiency-virus (HIV) infection in adults. This fixed combination replaces the three components (abacavir, lamivudine and zidovudine) used separately in similar dosages. It is recommended that treatment is started with abacavir, lamivudine,and zidovudine separately for the first six to eight weeks. The choice of this fixed combination should be based not only on potential adherence criteria, but mainly on expected efficacy and risk related to the three nucleoside analogues. The demonstration of the benefit of Trizivir is mainly based on results of studies performed in treatment naive patients or moderately antiretroviral experienced patients with non-advanced disease. In patients with high viral load (>100,000 copies/ml) choice of therapy needs special consideration. Overall, the virologic suppression with this triple nucleoside regimen could be inferior to that obtained with other multitherapies notably including boosted protease inhibitors or non-nucleoside reverse-transcriptase inhibitors, therefore the use of Trizivir should only be considered under special circumstances (e.g. co-infection with tuberculosis). Before initiating treatment with abacavir, screening for carriage of the HLA-B*5701 allele should be performed in any HIV-infected patient, irrespective of racial origin. Screening is also recommended prior to re-initiation of abacavir in patients of unknown HLA-B*5701 status who have previously tolerated abacavir (see 'management after an interruption of Trizivir therapy'). Abacavir should not be used in patients known to carry the HLA-B*5701 allele, unless no other therapeutic option is available in these patients, based on the treatment history and resistance testing.