Epidemiologic characteristics and natural history of HIV-1 natural viral suppressors.

OBJECTIVE: The objective of this study was to detail the epidemiologic characteristics and natural history of HIV-1 natural viral suppressors (NVSs), a cohort of HIV-1-infected individuals who are able to suppress viral replication to undetectable levels in the absence of therapy. DESIGN AND METHODS: HIV-1 patients who met the NVS criteria were enrolled into a prospective study. The incidence and prevalence of NVS were calculated by performing a chart review on all patients seen in 1 clinic in a 10-year period. Cumulative probability of progression-free survival was calculated by Kaplan-Meier product limit method.
RESULTS: Forty individuals enrolled in the study. The median year of diagnosis was 1994, and individuals demonstrated a median 6.7 years of HIV-1 viral suppression and CD4 count of 795 cells per microliter. NVS had an incidence of 1.1% [95% confidence interval (CI), 0.0 to 2.1] and prevalence of 1.5% (95% CI, 0.8 to 2.1). Only 1 patient (2.5%) has progressed. Within the first 10 years for follow-up having met the definition of NVS, 95.1% (95% CI 86.5% to 100%) of the NVS continued to control their viral loads to undetectable levels.
CONCLUSIONS: The NVS cohort has demonstrated remarkable stability and a low rate of progression over many years. Detailed evaluations of viral-host immune regulatory factors associated with persistent HIV-1 natural viral suppression, and loss of such suppression, has the potential to provide important new insight in HIV pathogenesis and future immune regulatory targeted preventive and therapeutic research.