- Poster presentation
- Open Access
Darunavir exhibits a potent activity as boosted PI in subjects on a salvage antiretroviral regimen
Journal of the International AIDS Society volume 11, Article number: P39 (2008)
Purpose of the study
This study aimed at testing the immuno-virological response in 20 consecutive HIV-1 infected patients treated with darunavir (DRV) within the early access program through 12 months of therapy. Evolution of drug resistance on HIV-RNA, on proviral DNA and proviral DNA quantification at different time points were carried out.
20 virologically multifailed subjects received a new HAART regimen composed by two NRTI and DRV as boosted PI; 16/20 were under T20 treatment. Immuno-virological response was determined through CD4+ cell counts and viral load (VL) detection. Genotypic analysis on HIV-RNA was performed from plasma samples at the baseline (BL) and on proviral DNA from PBMCs at different time points: BL, week 4, 12, 24, 36 and 48. HIV-RNA was extracted from patients with HIV-RNA >400 copies/mL and processed by RT-PCR. Nested-PCR for all samples was carried out in order to sequence pol and env gene, proviral DNA was quantified by real-time PCR.
Summary of results
Immune-virological status at BL showed a mean value of 248 CD4+ cells/μL and a viral load of 3.9 log10. After 12 months of therapy, we observed an increase in CD4+ count of 164 cells/μL and a decrease in HIV-RNA of 1.9 log10. We analyzed RNA mutations at BL in 13/20 patients and 11/13 showed the presence of at least one DRV mutation. The two most frequent DRV mutations were L33F (54%) and I84V (31%). BL proviral DNA showed changes in 7/20 patients. In 2/7, some mutations detected in RNA at BL mirrored in proviral DNA after one month of therapy. Mutational pattern at BL was more represented on HIV-RNA than on proviral DNA since the mean DRV mutational score was 4.4 for the former and 2.7 for the latter. During follow-up, 4/20 patients showed a progressive decrease of the DRV mutation number in the pro gene. After 12 months of treatment, all these subjects reverted to wild-type. On the contrary, restoration to a wild-type status did not occur in RT. No new mutation appeared on the env gene. Patients with high HIV-RNA at BL showed high levels in proviral DNA at the end of observation, whereas responders behaved in the opposite way.
We demonstrated that the immune-virological response during a DRV-including therapy was optimal in the majority of enrolled subjects. The decrease in the number of mutations during therapy is likely due to a reduced capacity in the DNA proviral integration under drug pressure and this might be confirmed by the proviral DNA quantification.
About this article
Cite this article
Vitiello, P., Ferramosca, S., Lo Cicero, M. et al. Darunavir exhibits a potent activity as boosted PI in subjects on a salvage antiretroviral regimen. JIAS 11, P39 (2008). https://doi.org/10.1186/1758-2652-11-S1-P39
- Viral Load
- Access Program
- Mutational Score
- Proviral Integration