Pharmacokinetics of a once-daily tacrolimus formulation in first nations and caucasian liver transplant recipients.

Patient ethnicity may influence the pharmacokinetics (PK) of tacrolimus. Because the Canadian First Nations (FN) constitute a large and increasing segment of the liver transplant population, we undertook to determine whether PK differences exist for a once-daily, extended release formulation of tacrolimus (Advagraf) in FN compared to Caucasian (CAUC) liver transplant recipients. Following achievement of a steady state with Advagraf, blood samples were drawn at 0, 1, 2, 4, 6, 8 and 24 hours for whole blood tacrolimus levels by commercial immunoassay and CYP3A4 and CYP3A5 allele analyses were performed by polymerase chain reactions. Nineteen subjects participated in the study (7 FN and 12 CAUC). The FN cohort had significantly higher AUC (214 ± 48 versus 168 ± 25, P < 0.05), Cmax (16.7 ± 4.4 ng/ml versus 11.3 ± 1.7 ng/ml, P < 0.05), Cmin (6.1 ± 1.0 ng/ml versus 4.7 ± 0.5 ng/ml, P < 0.05) and shorter Tmax (1.6 ± 0.2 hours versus 2.8 ± 0.3 hours, P < 0.05) values than CAUCs. CYP3A4 genotypes were C/C in both cohorts, while the CYP3A5 *1/*3 allele was present in 2/5 FN and 0/9 CAUC. The results of this study indicate that once-daily, extended release Advagraf results in higher blood tacrolimus levels and shorter times to Cmax in FN compared to CAUC liver transplant recipients.

Insulin secretion in liver transplant recipients following conversion to a prolonged release tacrolimus formulation.

Background: Post liver transplant diabetes mellitus (PLTDM) occurs in 10-40% of liver transplant recipients and is associated with increased morbidity and mortality. An important cause of PLTDM is tacrolimus induced, concentration-dependent, inhibition of insulin secretion. Objective: To determine if a newly licenced formulation of tacrolimus (Envarsus-PA), which achieves peak tacrolimus concentrations 20-30% lower than other tacrolimus formulations has less of an inhibitory effect on insulin secretion. Methods: Homeostatic model assessment (HOMA) for insulin secretion (HOMA-S) values and c-peptide levels were determined in 19 adult liver transplant recipients while being maintained on immediate- or slow-release tacrolimus formulations and repeated a minimum of 30 days following conversion to Envarsus-PA. Results: Insulin secretion was unchanged following conversion to Envarsus-PA (HOMA-S pre-conversion: 154 ± 133 vs. 129 ± 75, post-conversion [p = 0.32], and c-peptide levels; 1059 ± 602 and 934 ± 463 respectively, p = 0.42). Fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels were also unchanged (FBG 5.7 ± 0.8 pre-conversion vs. 5.6 ± 0.7 post-conversion; p = 0.36 and HbA1c 4.9±1.2 pre-conversion versus 5.5±0.2 post-conversion, p = 0.34). Conclusions: Envarsus-PA had no significant effect on insulin secretion or glucose homeostasis beyond that associated with other tacrolimus formulations in adult liver transplant recipients.

Post-transplant diabetes mellitus in Canadian liver and renal transplant recipients.

BACKGROUND: Post-transplant diabetes mellitus (PTDM) occurs in 10%-40% of liver and renal transplant recipients. Whether the risk factors for PTDM in liver and renal transplant recipients are similar and whether Indigenous Canadians, who have a high underlying prevalence of diabetes mellitus (DM), are at increased risk of developing PTDM have yet to be determined. OBJECTIVE: To describe and compare those variables associated with PTDM in adult Canadian liver and renal transplant recipients. METHODS: A retrospective chart review of adult liver and renal transplant recipients attending four transplant follow-up clinics in three Canadian provinces was undertaken. RESULTS: De novo PTDM was diagnosed in 184/905 (20.3%) liver and 179/390 (45.9%) renal transplant recipients. Older age, higher pre-transplant BMI, underlying immune-mediated liver disease, lower trough tacrolimus levels and longer duration of follow-up were independently associated with PTDM in liver transplant recipients and non-Caucasian race, higher pre-transplant BMI, and incidence of organ rejection in renal transplant recipients. Compared with Caucasians, Indigenous Canadians who had undergone renal transplantation had a significantly increased prevalence of PTDM (56.5% versus 40.0%, p = 0.035). The prevalence of PTDM in liver transplant recipients was similar in Indigenous Canadians and Caucasians (27.9% versus 20.1%, p = 0.215). CONCLUSIONS: The variables associated with PTDM differ in liver and renal transplant recipients. Compared with Caucasians, Indigenous Canadians undergoing renal transplantation are at increased risk of developing PTDM.

Low serum alkaline phosphatase levels in patients with chronic liver diseases: Possible contributions to disease pathogenesis.

OBJECTIVES: A low serum alkaline phosphatase (ALP) level is an uncommon finding in patients with chronic liver disease (CLD). The prevalence of this finding and whether low ALP expression influences CLD remain to be determined. The objectives of this study were: (1) to document the prevalence of low serum ALP levels in adult CLD patients and (2) compare features of CLD in patients with low versus normal or elevated serum ALP levels. METHODS: An adult, outpatient liver disease database was searched for patients with low serum ALP levels (<40 IU/L). Hepatic inflammation, function, fibrosis and disease severity were determined by serum aminotransferases, albumin, bilirubin and INR levels, Fib-4 calculations and MELD scores respectively. RESULTS: Of 19,037 patients entered into the database, 47 (0.25%) had consistently low serum ALP levels, 51 (0.27%) low levels on the majority and 469 (2.44%) on the minority of determinations. Patients with consistently low levels were matched (1:2) by age, gender and nature of the underlying liver disease to patients with normal or elevated serum ALP levels. Matched patients with consistently low ALP levels had significantly lower serum aminotransferase and bilirubin levels at their initial visit and throughout the follow-up period (p < 0.05 respectively) while Fib-4 levels and MELD scores were similar at the initial and last follow-up visit. CONCLUSIONS: These results establish the prevalence of low serum ALP levels in adult CLD patients and describe a hitherto unreported association between low serum ALP levels and less biochemical evidence of active disease.