Early Post-Transplantation Tacrolimus Levels Correlate with Acute Graft-Versus-Host Disease in Allogeneic Hematopoietic Stem Cell Transplantation from Related and Unrelated Donors

• Published in: Blood 2016-12, Vol.128 (22), p.3429-3429
• Main Authors: Hagen, Patrick A, Kobrinski, Daniel, Al-Mansour, Zeina, Tsai, Stephanie B., Parthasarathy, Mala, Kliethermes, Stephanie, Rodriguez, Tulio E., Smith, Scott E., Stiff, Patrick J.
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V128.22.3429.3429

Introduction: Acute graft-versus-host disease (aGVHD) is a leading cause of transplant related mortality following allogeneic hematopoietic stem cell transplantation (HCT). The most widely used aGVHD prophylaxis regimen is a combination of a calcineurin inhibitor and a short course of methotrexate. Results of studies on the optimal blood levels of the calcineurin inhibitor tacrolimus to prevent aGVHD are mixed, with some showing no correlation and others indicating that trough levels between 7-15 ng/mL required to adequately prevent aGVHD. Currently, the established target trough level for this agent is 10 to 20 ng/mL. We retrospectively evaluated the relationship between tacrolimus blood concentration and the incidence of grade II-IV aGVHD in a large cohort of adult patients following allogeneic HCT from either an HLA-matched related or matched unrelated donors. Methods: We evaluated all related/unrelated allografts between January 2004 and December 2012 at the Cardinal Bernardin Cancer Center at Loyola University. Inclusion criteria included age 18 years or older, first allogeneic HCT for a hematological malignancy, and use of tacrolimus and short term methotrexate for aGVHD prophylaxis. Donors included human leukocyte antigen (HLA) identical sibling (Allo-Sib) or unrelated donors (MUD) either fully matched or 1 antigen mismatched (10%). Both myeloablative and non-myeloablative conditioning regimens were included. Disease risk was defined by the ASBMT classification and Co-Morbidity Index by Sorror et al (HCT-CI). Infusional tacrolimus was initiated on day -2 of HCT at dose of 0.03 mg/kg/d and AM trough blood concentrations measured every other day during the entire hospital stay with the goal of maintaining a level of 10-15 ng/ml and then twice weekly after discharge. Dose adjustments or withholds were based primary on serum creatinine and trough levels per a set protocol that withholds for levels greater than 20 ng/ml or creatinine greater than 2.0 mg/dl. Acute GVHD was graded based on the International Bone Marrow Transplant Registry System. Univariate and multivariate analyses exploring all risk factors for aGVHD were performed. Results: A total of 428 patients met the inclusion criteria. Median age was 48.5 years with a male predominance (60.6%). HCT-CI was evenly distributed with 121 (28.2%) low risk, 151 (35.3%) intermediate risk, and 156 (36.4%) high risk. Per ASBMT disease risk classification, more patients had high disease risk (n=211, 49.3%);