Prophylaxis regimens for GVHD: systematic review and meta-analysis

Opinions are divided regarding the best prophylactic regimen for GVHD. The aim of this study was to evaluate potential survival benefit of different prophylactic regimens for acute GVHD (aGVHD). We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) including patients undergoing Allo-SCT. We included trials that assessed the addition of MTX, compared CsA and tacrolimus and evaluated the addition of steroids. Outcomes assessed were all-cause mortality (ACM) at the longest follow-up, aGVHD, chronic GVHD, TRM, relapse rate and regimen-specific adverse events. Relative risks (RRs) with 95% confidence intervals (CIs) were estimated and pooled. The regimen of MTX-CsA vs CsA alone (four trials) yielded no statistically significant difference in ACM (RR=0.84 (0.61-1.14)), but a significant decrease in aGVHD (RR=0.52 (0.39-0.7)). There was no difference in ACM for the comparison of MTX-CsA and MTX-tacrolimus (three trials); however, MTX-tacrolimus was superior to MTX-CsA in the reduction of aGVHD (RR=0.62 (0.52-0.75)) and severe aGVHD (RR=0.67 (0.47-0.95)). The addition of steroids did not affect the outcomes (four trials). We conclude that MTX-CsA and MTX-tacrolimus are both acceptable alternatives for GVHD prophylaxis, although MTX-tacrolimus may be superior in terms of aGVHD reduction.