Correlation between the Trofile test and virological response to a short-term maraviroc exposure in HIV-infected patients.
OBJECTIVE
The current validated assay to determine tropism of HIV variants is Trofile, which has some limitations. The aim of this work was to correlate the virological response to a short-term maraviroc exposure with Trofile.


METHODS
From 1 July 2008 to 1 March 2009, 34 consecutive HIV-infected patients with detectable viral load during the last 6 months began an 8 day exposure to maraviroc (MCT group); six HIV-infected patients without antiretroviral therapy received no treatment (control group). Plasma viral load was evaluated on days 0, 2, 5 and 8. Baseline Trofile was performed in MCT group patients. The maraviroc clinical test (MCT) was considered positive if viral load was undetectable (< 40 HIV-RNA copies/mL) or a reduction > or = 1 log(10) HIV-RNA copies/mL was achieved after 8 days of maraviroc exposure.


RESULTS
Global concordance between MCT and Trofile was 93.5%. In patients with R5 virus according to Trofile, MCT was positive in 19/20 (concordance 95%); in patients with dual/mixed virus, MCT was negative in 10/11 (concordance 90.9%). An additional phenotypic tropism assay was performed in patients with discordance between MCT and Trofile, being concordant with MCT in both cases. Three patients showed a non-reportable Trofile result, and all of them achieved undetectability after MCT.


CONCLUSIONS
A clinical approach like short-term maraviroc exposure could be an additional resource to genetic and phenotypic HIV tropism assays. This clinical approach shows high concordance with Trofile, and could allow patients with non-reportable results by Trofile to benefit from maraviroc therapy.
Genebat
Miguel
M
Laboratory of Immunovirology, Biomedicine Institute of Seville, Service of Infectious Diseases, Virgen del Rocío University Hospital, Seville, Spain.
Ruiz-Mateos
Ezequiel
E
León
Juan A
JA
González-Serna
Alejandro
A
Pulido
Ildefonso
I
Rivas
Inmaculada
I
Ferrando-Martínez
Sara
S
Sánchez
Berta
B
Muñoz-Fernández
Ma Angeles
MA
Leal
Manuel
M
D000293:Adolescent; D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D002648:Child; D003510:Cyclohexanes / Q000494:pharmacology*; D005260:Female; D006678:HIV / Q000187:drug effects* / Q000502:physiology*; D015658:HIV Infections / Q000821:virology*; D006801:Humans; D008297:Male; D000077592:Maraviroc; D008875:Middle Aged; D015728:Receptors, HIV / Q000032:analysis*; D014230:Triazoles / Q000494:pharmacology*; D019562:Viral Load; D055815:Young Adult
D019380:Anti-HIV Agents; D003510:Cyclohexanes; D015728:Receptors, HIV; D014230:Triazoles; D000077592:Maraviroc