title: ABCB1 genotypes predict cyclosporine-related adverse events and kidney allograft outcome.
abstract: Cyclosporine A (CsA) is a substrate of P-glycoprotein, an efflux transporter encoded by the ABCB1 gene. Compared with carriers of the wild-type gene, carriers of T allelic variants in exons 21 or 26 have reduced P-glycoprotein activity and, secondarily, increased intracellular concentration of CsA; therefore, carriers of T variants might be at increased risk for CsA-related adverse events. We evaluated the associations between ABCB1 genotypes (in exons 12, 21, and 26) and CsA-related outcomes in 147 renal transplant recipients who were receiving CsA-based immunosuppression and were included in the Mycophenolate Steroids Sparing study. During a median of 65.5 mo follow-up, carriers of T allelic variants in exons 21 or 26 had a three-fold risk for delayed graft function (DGF), a trend to slower recovery of renal function and lower GFR at study end, and significantly higher incidences of new-onset diabetes and cytomegalovirus reactivation compared with carriers of the wild-type genotype. T variants in both exons 21 and 26 were independently associated with 3.8- and 3.5-fold higher risk for DGF, respectively (P = 0.022 and P = 0.034). The incidence of acute rejection and the mean CsA dose and blood levels were comparable in genotype groups. In conclusion, renal transplant recipients with T allelic variants in ABCB1 exons 21 or 26 are at increased risk for CsA-related adverse events. Genetic evaluation may help to identify patients at risk and to modulate CsA therapy to optimize graft and patient outcomes.
authors.affiliation: Department of Medicine and Transplantation, Ospedali Riuniti-Mario Negri Institute for Pharmacological Research, Bergamo, Italy.
authors.forename: Dario
authors.initials: D
authors.lastname: Cattaneo
authors.forename: Piero
authors.initials: P
authors.lastname: Ruggenenti
authors.forename: Sara
authors.initials: S
authors.lastname: Baldelli
authors.forename: Nicola
authors.initials: N
authors.lastname: Motterlini
authors.forename: Eliana
authors.initials: E
authors.lastname: Gotti
authors.forename: Silvio
authors.initials: S
authors.lastname: Sandrini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Salvadori
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Segoloni
authors.forename: Paolo
authors.initials: P
authors.lastname: Rigotti
authors.forename: Donato
authors.initials: D
authors.lastname: Donati
authors.forename: Norberto
authors.initials: N
authors.lastname: Perico
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Remuzzi
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000328:Adult; D016572:Cyclosporine / Q000009:adverse effects*; D051799:Delayed Graft Function / Q000209:etiology*; D005260:Female; D005838:Genotype; D005919:Glomerular Filtration Rate; D006239:Haplotypes; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D007166:Immunosuppressive Agents; D016572:Cyclosporine