Baseline natural killer and T cell populations correlation with virologic outcome after regimen simplification to atazanavir/ritonavir alone (ACTG 5201).

TitleBaseline natural killer and T cell populations correlation with virologic outcome after regimen simplification to atazanavir/ritonavir alone (ACTG 5201).
Publication TypeJournal Article
Year of Publication2014
AuthorsMcKinnon JE, Mailliard RB, Swindells S, Wilkin TJ, Borowski L, Roper JM, Bastow B, Kearney M, Wiegand A, Mellors JW, Rinaldo CR
Corporate AuthorsA5201 study team
JournalPLoS One
Volume9
Issue5
Paginatione95524
Date Published2014
ISSN1932-6203
KeywordsAtazanavir Sulfate, CD4-CD8 Ratio, HIV Infections, HIV Protease Inhibitors, HIV-1, Humans, Killer Cells, Natural, Oligopeptides, Pyridines, Ritonavir, RNA, Viral
Abstract

OBJECTIVES: Simplified maintenance therapy with ritonavir-boosted atazanavir (ATV/r) provides an alternative treatment option for HIV-1 infection that spares nucleoside analogs (NRTI) for future use and decreased toxicity. We hypothesized that the level of immune activation (IA) and recovery of lymphocyte populations could influence virologic outcomes after regimen simplification.

METHODS: Thirty-four participants with virologic suppression ≥ 48 weeks on antiretroviral therapy (2 NRTI plus protease inhibitor) were switched to ATV/r alone in the context of the ACTG 5201 clinical trial. Flow cytometric analyses were performed on PBMC isolated from 25 patients with available samples, of which 24 had lymphocyte recovery sufficient for this study. Assessments included enumeration of T-cells (CD4/CD8), natural killer (NK) (CD3+CD56+CD16+) cells and cell-associated markers (HLA-DR, CD's 38/69/94/95/158/279).

RESULTS: Eight of the 24 patients had at least one plasma HIV-1 RNA level (VL) >50 copies/mL during the study. NK cell levels below the group median of 7.1% at study entry were associated with development of VL >50 copies/mL following simplification by regression and survival analyses (p = 0.043 and 0.023), with an odds ratio of 10.3 (95% CI: 1.92-55.3). Simplification was associated with transient increases in naïve and CD25+ CD4+ T-cells, and had no impact on IA levels.

CONCLUSIONS: Lower NK cell levels prior to regimen simplification were predictive of virologic rebound after discontinuation of nucleoside analogs. Regimen simplification did not have a sustained impact on markers of IA or T lymphocyte populations in 48 weeks of clinical monitoring.

TRIAL REGISTRATION: ClinicalTrials.gov NCT00084019.

DOI10.1371/journal.pone.0095524
Alternate JournalPLoS ONE
PubMed ID24802242
PubMed Central IDPMC4011688
Grant List1KL2- RR024154-03 / RR / NCRR NIH HHS / United States
1R21-AI084423-02 / AI / NIAID NIH HHS / United States
AI069450 / AI / NIAID NIH HHS / United States
R37-AI41870 / AI / NIAID NIH HHS / United States
U01 AI035041 / AI / NIAID NIH HHS / United States
U01 AI069423 / AI / NIAID NIH HHS / United States
U01-AI068636 / AI / NIAID NIH HHS / United States
U01-AI35041 / AI / NIAID NIH HHS / United States
UL1 RR024153 / RR / NCRR NIH HHS / United States
UM1 AI068636 / AI / NIAID NIH HHS / United States
UM1 AI069419 / AI / NIAID NIH HHS / United States
UM1 AI069494 / AI / NIAID NIH HHS / United States
UM1 AI106701 / AI / NIAID NIH HHS / United States