Effect of intermediate- and high-purity factor VIII concentrates on immune function in HIV-seropositive haemophiliacs as assessed by quantitative CD 4 counts.

Intermediate-purity factor VIII (FVIII) concentrates are believed to adversely influence cellular immune function and accelerate HIV progression in haemophiliac patients. There are reports that cellular immunity, as measured by serial CD4 lymphocyte counts, is better preserved in HIV-infected haemophiliacs who receive high-purity concentrates compared with those receiving intermediate- or low-purity products. We retrospectively evaluated the rate of CD4 cell count decrease in 44 asymptomatic HIV-seropositive severe haemophilia A patients whose purity of prescribed FVIII concentrate was primarily determined by State of residence. Prior to January 1989 all study subjects received treatment with intermediate- or low-purity products. In January 1989 the patients from Mississippi (n = 15) began to exclusively receive a high-purity, monoclonal antibody purified, plasma-derived product from their State Department of Health. The Mississippi cohort was subsequently converted to a high-purity, recombinant FVIII product in May 1993. Patients from Tennessee and Arkansas (n = 29) received intermediate-purity factor during the entire analysis period. Patients were monitored for an average of 68 months with an average of 11 CD4 cell count measurements. The rate of CD4 cell count decrease was derived from the calculated slope of a simple regression in order to account for large individual CD4 count fluctuations during the study period. There was no statistically significant difference in starting CD4 cell count between the 2 study groups. The rate of CD4 cell count decrease was 21.8 ± 52.9 cells μL(-1) year(-1) and 17.0 ± 32.6 cells μL(-1) year(-1) in the high-purity FVIII group and inter-mediate-purity FVIII group, respectively (P = 0.83). The difference in rate of CD4:CD8 ratio decrease between the two groups was also not statistically significant (P = 0.41). These data suggest that the use of the more costly, high-purity monoclonal antibody purified and recombinant FVIII concentrates does not influence the rate of decrease in CD4 cell count in HIV-seropositive haemophiliacs compared with concentrates of lower specific activity obtained using standard chromatographic techniques.