Nonstructured Treatment Interruptions Are Associated With Higher Human Immunodeficiency Virus Reservoir Size Measured by Intact Proviral DNA Assay in People Who Inject Drugs.

The latent reservoir for human immunodeficiency virus type 1 (HIV-1) in CD4+ T cells is a major barrier to cure. HIV-1-infected persons who inject drugs (PWID) often struggle to maintain suppression of viremia and experience nonstructured treatment interruptions (NTIs). The effects of injecting drugs or NTIs on the reservoir are unclear. Using the intact proviral DNA assay, we found no apparent effect of heroin or cocaine use on reservoir size. However, we found significantly larger reservoirs in those with frequent NTIs or a shorter interval from last detectable HIV RNA measurement. These results have important implications for inclusion of PWID in HIV-1 cure studies.