Effect of Conversion From Intravenous to Oral Administration on Cyclosporine Exposure in Pediatric Allogeneic Hematopoietic Stem Cell Transplantation.

BACKGROUND

Cyclosporine is an immunosuppressant extensively used for the prevention and treatment of graft-vs-host disease (GvHD) in pediatric allogeneic hematopoietic stem cell transplantation (allo-HSCT). Converting the administration route of cyclosporine from intravenous to oral is common in the early period of allo-HSCT. Various factors may have an impact on the conversion ratio of cyclosporine.

OBJECTIVE

To evaluate the effect of converting administration route from intravenous to oral on cyclosporine exposure in pediatric allo-HSCT recipients.

METHODS

Children who underwent allo-HSCT and were administered with cyclosporine for the prevention of GvHD were included. The cyclosporine trough concentration (C0), the trough concentration-dose ratio (CDR), and the conversion ratio were evaluated. Meanwhile, factors related to the bioavailability of cyclosporine were also investigated.

RESULTS

A total of 67 children with 280 concentrations were involved. The conversion ratio used in the study was approximately 1:2, and a significant decrease in cyclosporine CDR (110.5 vs 41.4 mg/kg per μg/L, P < 0.001) was observed. The overall bioavailability of cyclosporine was approximately 35%. Age younger than 3 years old (β = -10.70, 95% CI = -18.45 to -2.96, P = 0.007) and moderately increased transaminases (β = -17.95, 95% CI = -25.42 to -10.48, P < 0.001) had a significant impact on cyclosporine bioavailability.

CONCLUSIONS AND RELEVANCE: A conversion ratio of 1:3 was found to be more appropriate for pediatric allo-HSCT recipients when switching cyclosporine from intravenous to oral administration. Children younger than 3 years old or with moderately increased transaminases had significant lower cyclosporine bioavailability. These results can assist in an individualized approach for patients undergoing cyclosporine formulation switching.