Long-term benefit of genotypic-guided therapy and prevalence of multinucleoside resistance in an Italian group of antiretroviral multiexperienced patients.
Multiple nucleoside resistance involves specific genetic changes in the HIV-1 reverse transcriptase gene, such as Q151M mutation and an insertion of two serine aminoacids at RT codon 69. Among 432 patients failing antiretroviral therapy, five (1.15%) harboured viruses with Q151M mutation into the RT gene and no viruses were identified harbouring insertion at codon 69. Also we have studied the long-term benefit of HIV genotypic testing with the failure to reach a viral load below 50 copies/ml within 1 year of antiretroviral therapy using as the primary end-point. A group of 64 HIV-positive antiretroviral multiexperienced patients were examined, all of them failing the current ART. HIV-RNA changed -0.8 log at month 4 and +0.1 log and -0.5 log at months 8 and 12, respectively. The proportion of patients with viral load below 50 copies/ml was 19.3, 32.8, and 28.1% at months 4, 8, and 12, respectively. In multidrug-experienced patients, genotype-guided therapy is not in fact able to achieve complete viral suppression in more than 30% of patients after 1 year of ART. The development of more precise resistance tests and interpretations are needed for better control of HIV replication. Other metabolic/pharmacokinetics factors of poor drug adherence should also be assessed.
Quiros-Roldan
E
E
Institute of Infectious and Tropical Diseases, University of Brescia, Italy. Carosi@master.cci.unibs.it
Moretti
F
F
Airoldi
M
M
Fausti
C
C
Chiodera
A
A
Castelli
F
F
Carosi
G
G
D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy*; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D003062:Codon; D018432:Drug Resistance, Multiple / Q000235:genetics*; D005838:Genotype; D015497:HIV-1 / Q000235:genetics; D006801:Humans; D007558:Italy; D009154:Mutation; D012367:RNA, Viral / Q000032:analysis; D012194:RNA-Directed DNA Polymerase / Q000235:genetics*; D019562:Viral Load
D019380:Anti-HIV Agents; D003062:Codon; D012367:RNA, Viral; D012194:RNA-Directed DNA Polymerase