To discuss factors related to virologic failure and review data from recent clinical trials evaluating re-suppression of viremia in extensively-treated HIV-infected patients with resistance.
Factors associated with virologic failure can be related to the virus (e.g. resistance), the patient (e.g. adherence) or HIV therapy (e.g. availability) and must be analyzed to minimize the likelihood of a new failure. Recent clinical trials have shown that it is now possible to achieve virologic suppression in a large proportion of treatment-experienced patients with extensive drug resistance, with several newer agents demonstrating favorable potency, tolerability and long-term efficacy.
The benefits of highly active antiretroviral treatment are well recognized, and adding at least two (preferably three) new active drugs to an optimized background regimen can provide effective suppression of viremia even in multidrug-experienced patients. Changing drugs or regimen simplification should be considered when treatment is inadequate, poorly tolerated or associated with poor adherence, and is made easier by the newer agents and formulations now available. Newer antiretrovirals may contribute to a better quality of life and life expectancy in patients with few or no therapy options, although adherence is paramount in ensuring their continued effectiveness.
aInfectious Diseases Service, Centro Hospitalar do Porto, ECS – University of Minho
bClinical Immunology Unit, Centro Hospitalar do Porto, ICBAS
cInfectious Diseases Department (IDD) Hospital Garcia de Orta
dIDD Hospital de S. João
eIDD Hospitais da Universidade de Coimbra, and University of Coimbra, Portugal
Correspondence to Rui Sarmento-Castro, Infectious Diseases Service, Centro Hospitalar do Porto (Unidade Joaquim Urbano), Rua de Câmara Pestana 348, 4369-004, Porto, Portugal Tel: +351 225899550; fax: +351 225106160; e-mail: firstname.lastname@example.org