Triple-class virologic failure in HIV-infected patients undergoing antiretroviral therapy for up to 10 years

04 Mar, 2010

Authors: Lodwick R, Costagliola D, Reiss P, et al. Pursuing Later Treatment Options II (PLATO II) Project Team for the Collaboration of Observational HIV Epidemiological Research Europe (COHERE).

Published in: Archives of Internal Medicine. 2010; 170(5):410-419

Background: Life expectancy in people with HIV is now estimated to approach that in the general population in some successfully treated subgroups. However, to attain these life expectancies, viral suppression must be maintained for decades.

Methods: We studied the rate of triple class virologic failure (TCVF) in patients within the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) who started antiretroviral therapy (ART) with an NNRTI- or PI/r-containing regimen from 1998 onwards. We also focussed on TCVF in patients who started a PI/r-containing regimen after virologically failing a first-line NNRTI-containing regimen.

Results: Of 45937 patients followed for a median (IQR) 3.0 (1.5-5.0) years, 980 (2.1%) developed TCVF. By 5 and 9 years after starting ART, an estimated 3.4% (95% CI:3.1%-3.6%) and 8.6% (95% CI:7.5%-9.8%) of patients had developed TCVF. The incidence of TCVF rose during the first 3-4 years on ART, but plateaued thereafter. There was no significant difference in the risk of TCVF according to whether the initial regimen was NNRTI- or PI/r-based (p=0.11). By 5 years after starting a PI/r as second-line, 46% of patients had developed TCVF.

Conclusions: The rate of virologic failure of the three original drug classes is low, but not negligible, and does not appear to diminish over time from starting ART. If this trend continues, many patients are likely to need newer drugs to maintain viral suppression. The rate of TCVF from start of a PI/r after NNRTI failure provides a comparator for studies of response to secondline regimens in resource-limited settings.