Plasma HIV-1 RNA as a predictor of the efficacy of adding zalcitabine to a previous regimen with zidovudine.
The objective of this study was to determine whether or not plasma HIV-1 RNA levels, the syncytium-inducing phenotype assay or mutations at codon 215 of the gene encoding HIV-1 reverse transcriptase could have prognostic value in patients already undergoing therapy with zidovudine who were started on combination therapy with zidovudine and zalcitabine. A prospective study was performed in 37 HIV-1-infected individuals who had received at least 6 months (mean: 9 months; range: 6-24 months) of zidovudine to which zalcitabine was added. The mean initial CD4 cell count was 330 cells/mm3 (range: 20-520 cells/mm3). At baseline and at the end of the study (12 months), we analysed CD4 and CD8 cell counts, plasma HIV-1 RNA levels, the syncytium-inducing phenotype of virus isolated from peripheral blood mononuclear cells and mutations at codon 215 of the gene encoding reverse transcriptase. These variables were studied by Fisher's exact and U Mann-Whitney tests. There were statistically significant differences between progressor and non-progressor groups at baseline and after a 12-month period in the following parameters: CD4 and CD8 cell counts and HIV-1 RNA level (P < 0.05). Clinical progression occurred significantly more often in patients with CD4 cell counts < or = 300 cells/mm3 and HIV-1 RNA > 30000 copies/ml at baseline (P = 0.003). Moreover, we found that progression to AIDS only occurred in those patients whose viral load increased during the follow-up period and who had a CD4 cell count < 300 cells/mm3. Our results show the usefulness of HIV-1 RNA level as a surrogate marker for clinical outcome.
Ruiz
L
L
Retrovirology Laboratory Irsi-Caixa, Hospital Universitari Germans Trias i Pujol, Badalona, Universitat Autònoma de Barcelona, Spain.
Romeu
J
J
Ibáñez
A
A
Cabrera
C
C
Puig
T
T
Morales
M A
MA
Sirera
G
G
Clotet
B
B
D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D018791:CD4 Lymphocyte Count; D004359:Drug Therapy, Combination; D005260:Female; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood*; D016047:Zalcitabine / Q000008:administration & dosage*; D015215:Zidovudine / Q000008:administration & dosage*
D019380:Anti-HIV Agents; D012367:RNA, Viral; D015215:Zidovudine; D016047:Zalcitabine