Efficacy and safety of induction therapy with alemtuzumab in kidney transplantation: a meta-analysis.

Background: Alemtuzumab, a humanized CD52 monoclonal antibody, with its profound lymphocyte depletion property, was expected to be a promising induction therapy agent for kidney transplantation (KTx). However, currently no consensus is available about its efficacy and safety. The aim of this meta-analysis was to make a profound review and an objective appraisal of this issue.

Methods: Relevant papers were searched, essentially in the PubMed database and the Cochrane library. After a thorough review, randomized controlled trials (RCTs) comparing the outcome of KTx using alemtuzumab induction therapy (test group) with a control group were collected according to the inclusion criteria. Data of general characteristic of studies and major outcomes of Ktx were extracted and meta-analyses were performed with RevMan 4.2 software. The odds ratio (OR) with a 95% confidence intervals (CI) was the principle measurement of effect.

Results: Five RCTs were included. The chi square test showed no significant between-study heterogeneity, thus fixed effect model was employed. Sub-group analysis with studies including alemtuzumab induction followed by a tacrolimus-based immunosuppressive regimen showed that the acute rejection rate (ARR) was lower relative to the control (OR = 0.59, 95% CI 0.34 - 1.01, P = 0.05). However, meta-analysis with all included studies revealed that neither ARR nor patient/graft survival rates differ significantly between the test and the control group, but the cytomegalovirus (CMV) infection rate was higher in the test group (OR 2.50, 95% CI 1.22 - 5.12, P = 0.01). A great number of the test group recipients safely remained on a regimen that was steroid-free and with a reduced dose of conventional immunosuppressive drugs.

Conclusions: Alemtuzumab induction therapy for KTx was an effective and safe protocol in the tested follow-up period. Steroid avoidance and a dose reduction of conventional immunosuppressive drugs after alemtuzumab induction therapy may have clinical importance. However, high quality RCTs with larger population and longer follow-up are needed for a more accurate and objective appraisal of this novel protocol.