HIV Remission After Allogeneic Stem Cell Transplantation: Conclusions From 10 Successful Cases

Approximately 100 000 people in Germany are now living with human immunodeficiency virus (HIV), with 2300 new cases per year. A cure for HIV infection was long considered unattainable. The first patient to achieve sustained HIV remission after allogeneic hematopoietic stem cell transplantation (allo-HSCT) was treated in Berlin, providing proof of principle. In this review, we summarize the cases of sustained HIV remission after allo-HSCT published to date and classify them with regard to possible underlying mechanisms. We also discuss the prospects for future curative strategies.

This review is based on relevant publications retrieved by searches in PubMed and the international IciStem database, as well as the authors' longstanding scientific experience and international scientific exchange. Published cases of sustained HIV remission after allo-HSCT and discontinuation of ART were included in the review.

After the initial patient in Berlin, nine further cases of sustained HIV remission after allo-HSCT have been reported to date. Eight of the ten patients received donor cells with a homozygous 32-base-pair deletion in the gene for the C-C chemokine receptor type 5 (CCR5Δ32/Δ32), which leads to loss of the CCR5 receptor on the cell surface and thus resistance to CCR5-tropic HIV variants. In the other two patients, sustained remission was achieved without the homozygous mutation: The Geneva patient received wild-type CCR5 donor cells, and the second Berlin patient received cells from a heterozygous donor (CCR5WT/Δ32).

These cases demonstrate that allo-HSCT can lead to sustained remission. Along with the approach used in SHIV-infected monkeys, in which remission was achieved by inducing anti-CCR5 autoantibodies, they yield insights into strategies beyond allo-HSCT.