The CCR5 Delta 32 allele slows disease progression of human immunodeficiency virus-1-infected children receiving antiretroviral treatment

The role of the CCR5 Delta 32 allele in human immunodeficiency virus (HIV)- 1-related disease progression was analyzed for 457 antiretroviral-naive chi ldren who had participated in the Pediatric AIDS Clinical Trials Group 152 study, which demonstrated that didanosine (ddI) or zidovudine + ddI treatme nts were superior to zidovudine alone. The CCR5 Delta 32 allele was detecte d at an overall frequency of 6.1% (28/457). At study entry, heterozygote ch ildren (wild type [wt]/Delta 32) had higher baseline median CD4(+) counts/m m(3) than wt/wt children had (1035 vs. 835 cells/mm(3); P = .043), higher m ean weight-for-age Z scores (-0.15 vs. -0.84; P = .01), and a trend toward less cortical atrophy (P = .059). During antiretroviral treatment and study follow-up, there was a trend toward less disease progression and death amo ng heterozygote children than among,wt/wt children (P = .056; relative haza rd, 0.28; 95% confidence interval, 0.07-1.13) independent of the antiretrov iral treatment to which they were randomized.