Randomized Controlled Trial Assessing the Impact of Tacrolimus Versus Cyclosporine on the Incidence of Posttransplant Diabetes Mellitus

INTRODUCTION

Despite the high incidence of posttransplant diabetes mellitus (PTDM) among high-risk recipients, no studies have investigated its prevention by immunosuppression optimization.

METHODS

We conducted an open-label, multicenter, randomized trial testing whether a tacrolimus-based immunosuppression and rapid steroid withdrawal (SW) within 1 week (Tac-SW) or cyclosporine A (CsA) with steroid minimization (SM) (CsA-SM), decreased the incidence of PTDM compared with tacrolimus with SM (Tac-SM). All arms received basiliximab and mycophenolate mofetil. High risk was defined by age >60 or >45 years plus metabolic criteria based on body mass index, triglycerides, and high-density lipoprotein-cholesterol levels. The primary endpoint was the incidence of PTDM after 12 months.

RESULTS

The study comprised 128 de novo renal transplant recipients without pretransplant diabetes (Tac-SW: 44, Tac-SM: 42, CsA-SM: 42). The 1-year incidence of PTDM in each arm was 37.8% for Tac-SW, 25.7% for Tac-SM, and 9.7% for CsA-SM (relative risk [RR] Tac-SW vs. CsA-SM 3.9 [1.2-12.4; P = 0.01]; RR Tac-SM vs. CsA-SM 2.7 [0.8-8.9; P = 0.1]). Antidiabetic therapy was required less commonly in the CsA-SM arm (P = 0.06); however, acute rejection rate was higher in CsA-SM arm (Tac-SW 11.4%, Tac-SM 4.8%, and CsA-SM 21.4% of patients; cumulative incidence P = 0.04). Graft and patient survival, and graft function were similar among arms.

CONCLUSION

In high-risk patients, tacrolimus-based immunosuppression with SM provides the best balance between PTDM and acute rejection incidence.

Synthesis and structure of the cluster ion pair [Ru3(CO)9[mu-P(NPri2)2]3][Ru6(CO)15(mu 6-C)[mu-P(NPri2)2]]. A theoretical overview of M3(mu-PR2)3 frameworks

The compound [Ru3(CO)9[mu-P(NPri2)2]3][Ru6(CO)15(mu 6-C)[mu-P(NPri2)2]] (1), obtained via the addition of PCl(NPri2)2 to K2[Ru4(CO)13], crystallizes in the monoclinic space group P2l/c with a = 15.537(8) A, b = 36.151(16) A, c = 19.407(5) A, beta = 91.14(2) degrees, Z = 4, and R = 0.069 for 8006 observed reflections. The unit cell is unusual in that it contains both a typical octahedral Ru6 cluster anion (1a), featuring an encapsulated carbide, and a symmetrical phosphido bridge, in addition to a 50-electron trinuclear cluster cation [Ru3(CO)9[mu-P(NPri2)2]3]+ (1c). The latter, with approximate D3h symmetry, exhibits long Ru-Ru distances (> or = 3.15 A). Among the family of clusters with M3(mu-PR2)3 cores and different numbers of both electrons (TEC) and terminal ligands (LxLyLz), 1c is unique in that it is a 333 stereotype with 50 valence electrons. MO calculations permit us to predict the existence of redox congeners of 1c clusters and related 48e Re3 clusters. This work also presents a summary of the relationships between the electronic and the geometric structures for all known M3LxLyLz(mu-PR2)3 species. The basic stereochemical features are influenced by the total-electron count and, hence, by the degree of M-M bonding, as well as the remarkable flexibility of the phosphido bridging ligands. The mu-PR2 ligands need not necessarily lie in the M3 plane, and a wide range of M-P-M angles (as small as 72 degrees or as large as 133 degrees) have been observed.