Novel antibodies which have an impact on immune status after allogeneic hematopoietic cell transplantation

In the field of hematological malignancy, we often have the opportunity to use antibodies such as immune checkpoint inhibitors that can alter a patient's immune status before or after allo-HCT. The appropriate use of these novel agents is highly necessary to optimize disease control and reduce the risk of complications associated with adverse allo-immune reactions.

Clinical data on several monoclonal antibodies targeting programmed cell death 1 (PD-1) (nivolumab or pembrolizumab), C-C chemokine receptor 4 (CCR4) (mogamulizumab), CD30 (brentuximab vedotin), or cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) (ipilimumab) are reviewed, with a focus on the incidence and severity of graft-versus-host disease (GVHD).

While previous studies demonstrated a favorable prognosis in patients who received nivolumab prior to transplantation, the pretransplant use of nivolumab increases the incidence of GVHD, partly due to the expansion and activation of preexisting T cells. Mogamulizumab also has a significant impact on GVHD, caused by persistent depletion of regulatory T cells with CCR4 positivity. Regarding brentuximab vedotin, phase 1 trials have demonstrated considerable efficacy for steroid-refractory acute or chronic GVHD. In the future, sophisticated methods will be needed to determine the impact of each agent on immune status after allo-HCT.