Sustained HIV remission after allogeneic hematopoietic stem cell transplantation with wild-type CCR5 donor cells

Abstract

HIV cure has been reported for five individuals who received allogeneic hematopoietic stem cell transplant (allo-HSCT) from CCR5Δ32 homozygous donors. In contrast, viral rebound has occurred in other people living with HIV who interrupted antiretroviral treatment after receiving allo-HSCT, mostly from wild-type CCR5 donors. Here, we report the case of a male who has achieved durable HIV remission following allo-HSCT from an unrelated HLA-matched (9/10 matching for HLA-A, -B, -C, -DRB1 and -DQB1 alleles) wild-type CCR5 donor to treat an extramedullary myeloid tumor. To date, plasma viral load has remained undetectable for 32 months after the interruption of antiretroviral treatment. Treatment with ruxolitinib has been maintained during this period to treat chronic graft versus host disease. Low levels of proviral DNA were detected sporadically post-allo-HSCT, including defective but not intact HIV DNA. No virus could be amplified in cultures of CD4 + T cells obtained post antiretroviral treatment interruption, while CD4 + T cells remained susceptible to HIV-1 infection in vitro. Decline of HIV antibodies and undetectable HIV-specific T cell responses further corroborate the absence of viral rebound after antiretroviral treatment interruption. These results suggest that HIV remission could be achieved in the context of allo-HSCT with wild-type CCR5.