Antibodies to E. coli-produced HIV-1 nef, rev, tat, vpu, and vpr proteins were measured by enzyme immunoassay in serial sets of sera from 72 men seroconverting for antibodies to HIV-1 structural proteins, and from 190 initially symptom-free men who were seropositive for these antibodies at entry into the study. In the men seroconverting for antibodies to structural proteins the levels of nef-, rev-, and tat-specific antibodies, but not of vpu-, and vpr-specific antibodies, within 3 months of seroconversion, appeared to be lower in the five men progressing to AIDS, compared with the men remaining symptom-free during follow-up. Analysis of the prevalence of previously described antibody profiles to these accessory gene products was carried out. In all HIV-1 antibody seroconverters and in those HIV-1 antibody seropositive men with 15 or more months of follow-up who progressed to AIDS, there was a shift from predominantly nef- and vpu-specific antibody negative profiles in the men developing AIDS in the early years of the study to predominantly nef- and vpu-specific antibody positive profiles in men who developed AIDS later. Rev- and tat-specific antibody negative profiles were dominant in men progressing to AIDS throughout follow-up. No vpr-specific antibody profile occurred preferentially in the men progressing to AIDS throughout follow-up. Low antibody reactivity to accessory gene products nef, rev, and tat appears, like low anti-core antibody reactivity, to be associated with progression to AIDS relatively rapidly after infection with HIV-1.