(HealthDay News) – Early in the course of primary HIV-1 infection, a 48-week session of antiretroviral therapy (ART) delays disease progression vs. no ART; and initiation of ART >4 months after the estimated start date of HIV infection reduces the likelihood of CD4+ T-cell count recovery, according to two studies published in the Jan. 17 issue of the New England Journal of Medicine.
Sarah Fidler, MB, BS, PhD, from Imperial College London, and colleagues examined disease progression among 366 HIV-1 infected adults (60% men) who were randomized to 48 weeks, 12 weeks, or no ART (standard care). During an average follow-up of 4.2 years, the researchers found that the primary end point (having a CD4+ count of <350 cells per mm³ or initiation of long-term ART) was achieved by 50% of the 48-week ART group vs. 61% in each of the other groups (average hazard ratio, 0.63 for 48-week ART vs. standard care).
Tuan Le, MD, DrPh, of the South Texas Veterans Health Care System in San Antonio, and colleagues examined the correlation between the timing of ART initiation and CD4+ T-cell count recovery. The researchers found that, among a cohort of 384 participants who were not receiving ART, CD4+ T-cell counts increased spontaneously within about four months of the estimated start date of the infection and then decreased. For 213 participants who received ART, the likelihood of recovery of CD4+ counts was significantly lower (odds ratio, 0.35) and the rate of recovery slower (rate ratio, 0.44) with later initiation (>four months after the estimated start date of infection).
“The initiation of ART within this early restorative time window, when the host immune system is poised for recovery, greatly accelerates the pace and augments the extent of CD4+ T-cell recovery,” Le and colleagues write.
Several authors from both studies disclosed financial ties to the pharmaceutical industry.