Changes in viral load in people with virological failure who remain on the same HAART regimen.
OBJECTIVE
To assess the rate of change in viral load and CD4 count over time in HIV-infected patients experiencing virological failure on a HAART regimen.


METHODS
Study population included patients from EuroSIDA, a large, multicentre, observational study enrolling HIV-infected patients across Europe.


METHODS
Median change in viral load and CD4 count per month were estimated using the viral load and CD4 measurements obtained over a 12-month period after confirmed virological failure between 3 and 4 log10 copies/ml in a population of 488 HIV-infected patients who were left on a failing HAART regimen.


RESULTS
The estimated median viral load change in our study population was 0.024 log10 copies/ml per month, statistically different from 0 (P=0.0001). In 20.9% of the patients studied viral load showed a tendency to decrease, in 47.8% showed a tendency to increase by a positive rate no higher than 0.04 log10 copies/ml per month and in the remaining 31.3% showed a tendency to increase by a rate greater than 0.04 log10 copies/ml per month. On average, CD4 counts were estimated to remain stable (decrease at a slow rate of about -0.53 cells/microl per month).


CONCLUSIONS
In patients that remained on a stable, but virologically failing HAART regimen (with viral load ranging 1000-10000 copies/ml), the viral load over the ensuing 12-month period increased at a relatively slow rate. In contrast, the CD4 count remained stable, possibly because of partial but sustained viral suppression below the viral load natural set-point. The time-course of selecting more replication-competent virus in patients with virological failure remains to be fully clarified.
Cozzi-Lepri
Alessandro
A
Royal Free Centre for HIV Medicine & Department of Primary Care and Population Sciences, Royal Free and University College Medical School, Royal Free Campus, London, UK.
Phillips
Andrew N
AN
Miller
Veronica
V
Katlama
Christine
C
Ledergerber
Bruno
B
Vella
Stefano
S
Weber
Jonathan
J
Bruun
Johan N
JN
Kirk
Ole
O
Clotet
Bonaventura
B
Lundgrens
Jens D
JD
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D016208:Databases, Factual; D004359:Drug Therapy, Combination; D005060:Europe; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D006801:Humans; D008297:Male; D015337:Multicenter Studies as Topic; D012189:Retrospective Studies; D012985:Software Design; D013997:Time Factors; D017211:Treatment Failure; D019562:Viral Load
D019380:Anti-HIV Agents