Preliminary experience with alemtuzumab induction therapy combined with maintenance low-dose tacrolimus monotherapy in small-bowel transplantation in China

Abstract

Introduction: The goal of combining alemtuzumab induction therapy with low-dose tacrolimus monotherapy in small-bowel transplantation (SBTx) is to enable improved graft acceptance without immunologic unresponsiveness caused by stronger immunosuppression regimens. Herein, we report preliminary experience using this protocol in 5 patients who underwent SBTx in China.

Methods: Patients received methylprednisolone sodium succinate (Solu-Medrol), 1 g, followed by alemtuzumab infusion, 30 mg, during SBTx and another gram of prednisolone before reperfusion. Tacrolimus monotherapy without steroid was used for maintenance immunosuppression. Tacrolimus trough levels were 10 to 15 ng/dL during the first 3 months, and weaned to 5 to 10 ng/mL after 3 months.

Results: Three recipients have survived for longer than 1 year; 1 patient is currently alive at 9 months, and another at 5 months post-SBTx. Grafts in these 5 recipients achieved excellent function, and in all patients, total parenteral nutrition was discontinued at 2 to 3 weeks postoperatively and normal oral intake was resumed. One recipient died at 13 months post-SBTx of severe rejection; the condition of the other 4 recipients who were still alive was good. Pathologic analysis of ileoscopic biopsy specimens revealed 4 episodes of indeterminate to mild acute cellular rejection (ACR) at 1 to 3 months, 3 episodes of indeterminate to mild ACR at 4 to 6 months, 3 episodes of moderate ACR at 7 to 12 months, and 1 episode of severe ACR at 13 months. All episodes of indeterminate to moderate ACR were totally resolved; only treatment of severe ACR failed. One patient experienced an episode of invasive fungal infection and another episode of cytomegaloviral infection, with total recovery after treatment.

Conclusions: Our preliminary experience in these 5 cases showed that the protocol combining alemtuzumab induction therapy with low-dose tacrolimus monotherapy without maintenance steroid therapy past-SBTx can effectively control rejection with excellent graft function. Nevertheless, close surveillance of ACR should be still performed after 6 months.