Interruption of antiretroviral treatment in HIV-infected patients with preserved immune function is associated with a low rate of clinical progression: a prospective study by AIDS Clinical Trials Group 5170.
BACKGROUND
We sought to determine the safety of treatment interruption (TI) and to identify parameters that would define patients with human immunodeficiency virus (HIV) for whom TI is safer.


METHODS
AIDS Clinical Trials Group 5170 was a multicenter, 96-week-long, prospective study of HIV-infected patients receiving antiretroviral therapy (ART) who had CD4(+) cell counts >350 cells/mm(3) and who underwent TI.


RESULTS
A total of 167 patients were enrolled. The median nadir in CD4(+) cell count was 436 cells/mm(3). The initial decrease (i.e., during the first 8 weeks) in CD4(+) cell count after ART interruption was 20 cells/mm(3)/week; the subsequent decrease was 2.0 cells/mm(3)/week until week 96. Both the CD4(+) cell count before enrollment and the increase in CD4(+) cell count during ART predicted early decrease; later decrease was predicted by the level of interleukin-7 at enrollment. A Centers for Disease Control and Prevention (CDC) diagnosis of a category B or C event was made for 2 and 2 patients, respectively (all had CD4(+) cell counts >350 cells/mm(3)). At week 96, 17 patients had CD4(+) cell counts < or =250 cells/mm(3), and 46 patients had resumed ART; 5 patients died (unrelated to HIV or acquired immunodeficiency syndrome). In a multivariate analysis, a higher nadir in CD4(+) cell count (>400 cells/mm(3)), a lower HIV load (<50 copies/mL) at the time of TI, and an HIV load < or =22,000 copies/mL before ART predicted a longer time to the primary end point (CDC category B or C event, death, CD4(+) cell count < or =250 cells/mm(3), or resumption of ART).


CONCLUSIONS
Disease progression after TI was low in this cohort. A higher nadir in CD4(+) cell count, a lower HIV load before ART, and an HIV load < or =50 copies/mL at the time of TI predicted a longer time to the primary end point.
Skiest
Daniel J
DJ
Baystate Medical Center, Springfield, MA 01106, USA. daniel.skiest@bhs.org
Su
Zhaohui
Z
Havlir
Diane V
DV
Robertson
Kevin R
KR
Coombs
Robert W
RW
Cain
Pat
P
Peterson
Tianna
T
Krambrink
Amy
A
Jahed
Nasreen
N
McMahon
Deborah
D
Margolis
David M
DM
D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000276:immunology* / Q000401:mortality; D000328:Adult; D019380:Anti-HIV Agents / Q000009:adverse effects / Q000627:therapeutic use*; D044966:Anti-Retroviral Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D018579:Patient Selection; D011446:Prospective Studies; D016019:Survival Analysis; D019562:Viral Load
D019380:Anti-HIV Agents; D044966:Anti-Retroviral Agents