Your browser version may not work well with NCBI's Web applications. More information here...
1: Transplantation. 2004 Jul 15;78(1):21-5. Links

MDR-1 C3435T polymorphism influences cyclosporine a dose requirement in liver-transplant recipients.

Service Pharmacie-Pharmacologie, Hôpital Paul Brousse, Villejuif, France. laurence.bonhomme-faivre@pbr.ap-hop-paris.fr

BACKGROUND: Cyclosporine A (CsA) is characterized by high interindividual variations in oral bioavailability and a narrow therapeutic index. CsA is a substrate for P-glycoprotein, a member of the ABC transporter family encoded by the multiple drug-resistant gene MDR1. METHODS: Because MDR1 gene exon 26 C3435T polymorphism influences intestinal P-glycoprotein expression, we investigated whether this polymorphism was correlated with variation in CsA dose requirement and concentration/dose ratio in 44 liver-transplant recipients during 1 month after transplantation. CsA concentration was measured 2 hours after administration (C2), according to international recommendations. RESULTS: The MDR-1 wild-type genotype (3435CC) was observed in 15 patients (34%), whereas 21 (48%) patients were heterozygous (3435CT), and 8 (18%) patients were homozygous for the mutation (3435TT). There was no significant difference between the three groups regarding corticosteroids treatment or renal function during this period. One to 3 days after liver transplantation, when every patient received a similar CsA weight-adjusted dose, the concentration/dose ratio was correlated with exon 26 single nucleotide polymorphism and was significantly higher in subjects homozygous for the mutation (P=0.012). This was confirmed 1 month after transplantation (P=0.049), when the dose was adjusted to maintain the C2 target level of 1,000 microg/L and we observed that TT patients required approximately 50% lower weight-adjusted CsA dose than wild-type patients (P=0,033). CONCLUSIONS: These findings demonstrate that the MDR1 exon 26 C3435T polymorphism is a major determinant of CsA concentration/dose ratio in liver-transplant recipients and is predictive of the dose of CsA to be administered to achieve the target C(2) concentration.

PMID: 15257034 [PubMed - indexed for MEDLINE]

Patient Drug Information

  • Cyclosporine (Neoral® , Sandimmune® , Gengraf® )

    Cyclosporine and cyclosporine (modified) are used with other medications to prevent transplant rejection (attack of the transplanted organ by the immune system of the person who received the organ) in people who have rec...