Substitution of calcineurin inhibitors with corticosteroids after allogeneic hematopoietic cell transplantation.

Combination of calcineurin inhibitors (CIs) with short-term methotrexate is a standard prophylactic regimen for graft-versus-host disease (GVHD). However, it is sometimes difficult to continue CIs due to adverse effects, such as renal impairment and fluid overload. In such cases, we replace CIs with corticosteroids, considering that full dose of CIs is equivalent to prednisolone (PSL) at 1 mg/kg. We retrospectively evaluated the clinical significance of replacement of CIs with corticosteroids after allogeneic hematopoietic cell transplantation (HCT). We evaluated 42 patients switched from CIs to corticosteroids within 90 days among the 479 patients who underwent allogeneic HCT at our center between 2007 and 2019. Renal impairment (n = 33), fluid overload (n = 13), and thrombotic microangiopathy (n = 3) were the main reasons for switching. Although creatinine and body weight returned to baseline at 4 weeks after switching, 100-day non-relapse mortality was high (57.1%). Grade II-IV acute GVHD was seen in 10 (24.4%) patients who did not have it before switching treatment (n = 41). In conclusion, CIs were switched to corticosteroids in patients with severe clinical conditions. The incidence of acute GVHD was acceptable. Although the short-term mortality rate was high, improvement of renal function or fluid overload was observed in a certain proportion of the patients.