title: Significant prolongation of renal allograft survival by delayed combination therapy of FK778 with tacrolimus in nonhuman primates.
abstract: BACKGROUND
  Malononitrilamide 715 (FK778) is a new class of low-molecular-weight immunosuppressant that is a derivative of the active metabolite of leflunomide, A77 1726. In this study, the authors evaluated the combined effect of FK778 with tacrolimus in prevention of renal allograft rejection in Vervet monkeys.
  
  
  METHODS
  Male Vervet monkeys were obtained from Caribbean Primates Ltd. Donor and recipient monkeys were from different breeding colonies. Eleven groups (n>or=4 per group) were involved in this study. FK778 and tacrolimus were administered orally for 60 days according to protocol.
  
  
  RESULTS
  Naive controls rejected renal grafts, with a median survival time (MST) of 8.0 days in group 1. When recipient monkeys were treated with tacrolimus 1.0 mg/kg/day in group 2 or FK778 2.5 mg/kg/day in group 3, the MST was 16.0 days (P=0.001) and 11.0 days (P=0.266), respectively. Combination therapy of these two agents at the same doses immediately after transplantation resulted in an MST of 25.0 days (P=0.016) in group 4. When tacrolimus was initiated immediately after transplantation and FK778 treatment was delayed until day 7 after surgery in group 5, recipient survivals were significantly prolonged to 38.0 days (P=0.02). These results were repeatable when FK778 5.0 mg/kg/day (9.0 days, P=0.544 in group 6) was combined with tacrolimus 1.0 mg/kg/day immediately after transplantation (8.0 days, P=0.339) in group 7, or when FK778 was delayed 7 days (60.0 days, P=0.002) in group 8. Furthermore, it was also repeatable when FK778 10 mg/kg/day was combined with tacrolimus 1.0 mg/kg/day with a 7-day delay.
  
  
  CONCLUSIONS
  A significant prolongation of renal allograft survival was produced when FK778 administration was delayed by 7 days combined with tacrolimus in Vervet monkeys.
authors.affiliation: Laboratory of Experimental Surgery, Research Center of CHUM, Notre-Dame Hospital, University of Montreal, Montreal, Quebec, Canada.
authors.forename: Shijie
authors.initials: S
authors.lastname: Qi
authors.forename: Shengyun
authors.initials: S
authors.lastname: Zhu
authors.forename: Dasheng
authors.initials: D
authors.lastname: Xu
authors.forename: Xiang
authors.initials: X
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Ouyang
authors.forename: Wenlei
authors.initials: W
authors.lastname: Jiang
authors.forename: Minh Diem
authors.initials: MD
authors.lastname: Vu
authors.forename: Kupa
authors.initials: K
authors.lastname: Bilolo
authors.forename: Anlun
authors.initials: A
authors.lastname: Ma
authors.forename: Stephane
authors.initials: S
authors.lastname: Johnson
authors.forename: Pierre
authors.initials: P
authors.lastname: Daloze
authors.forename: Ihor
authors.initials: I
authors.lastname: Bekersky
authors.forename: William E
authors.initials: WE
authors.lastname: Fitzsimmons
authors.forename: Huifang
authors.initials: H
authors.lastname: Chen
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000480:Alkynes; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001835:Body Weight; D002522:Chlorocebus aethiops; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D006085:Graft Survival / Q000187:drug effects*; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D007555:Isoxazoles / Q000008:administration & dosage*; D007668:Kidney / Q000503:physiopathology; D016030:Kidney Transplantation; D008099:Liver / Q000503:physiopathology; D008297:Male; D009570:Nitriles; D016559:Tacrolimus / Q000008:administration & dosage*; D013997:Time Factors
chemical_list: D000480:Alkynes; D007166:Immunosuppressive Agents; D007555:Isoxazoles; D009570:Nitriles; C115284:2-cyano-3-hydroxy-N-(4-(trifluoromethyl)phenyl)-2-hepten-6-ynamide; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D016559:Tacrolimus