Effects of different routes of cyclosporin A administration on blood levels in patients undergoing bone marrow transplantation

Abstract

This follow-up study has been carried out on 15 bone marrow transplant recipients treated intravenously with cyclosporin A (CsA) as a bolus (1.25–2.5 mg/kg/12 h) or by continuous infusion (1–3 mg/kg/24 h) from −2 until the 21st day after transplantation. All patients were subsequently treated with CsA orally at a starting dose of 6.25 mg/kg/12 h; this starting dose was then adjusted on the basis of CsA blood levels until the 60th day after transplantation, followed by progressive reduction and withdrawal within 6–12 months. In whole blood, trough levels of polyclonal (P) and monoclonal (M) CsA were monitored by a FPIA method and the polyclonal/monoclonal ratio (P/M) was calculated. This ratio was lower during CsA administration as a bolus or by continuous infusion than during oral administration; the decrease was statistically significant. This difference was probably due to first-pass metabolism which occurs in the liver and gut after oral administration.