Cell and tissue therapy regulation: worldwide status and harmonization.

Rapid developments in scientific and technological aspects in stem cell biology and tissue engineering have led to the increased use of human cells and tissues for the treatment of various diseases and injuries. The regulatory environment for CTT products is rapidly evolving and drug regulatory agencies are working towards establishment of a risk-based system with some common features. Various drug regulatory agencies in many countries/regions have implemented regulatory controls in the last few years.

Mechanism-based enterohepatic circulation model of mycophenolic acid and its glucuronide metabolite: assessment of impact of cyclosporine dose in Asian renal transplant patients.

Mycophenolic acid (MPA) is mainly metabolized to MPA-glucuronide (MPAG), which may be reconverted to MPA following enterohepatic circulation (EHC). A physiologically realistic EHC model was proposed to estimate and assess the impact of cyclosporine (CsA) dose on the extent of EHC of MPA and MPAG. After the first oral dose of mycophenolate mofetil (MMF), the MPA and MPAG plasma concentration-time data of 14 adult renal transplant patients (12 receiving concomitant CsA and prednisolone and 2 receiving only concomitant prednisolone without CsA) were analyzed by individual pharmacokinetic modeling using a proposed 5-compartment drug and metabolite EHC model with a time-varying gallbladder emptying process.

Is a standard fixed dose of mycophenolate mofetil ideal for all patients?

Background: A standard fixed dose of 2 g/day of mycophenolate mofetil (MMF), irrespective of total body weight (TBW), is recommended when used in combination with cyclosporine and corticosteroids in renal transplantation.

Methods: To determine the optimal MMF dose in a population with wide variation in TBW, steady-state pharmacokinetics of mycophenolic acid (MPA) was performed in 53 Asian (Chinese, Malay, Indian, Eurasian) renal transplant recipients (RTX) receiving MMF [250-1000 mg twice daily (BD)] for at least 3 months. Blood samples were collected at 0, 0.

Simple reversed-phase liquid chromatographic assay for simultaneous quantification of free mycophenolic acid and its glucuronide metabolite in human plasma.

A reversed-phase HPLC-UV method, involving simple instrumental setup and mobile phase without ion-pairing reagent, was developed and validated for direct simultaneous quantification of free mycophenolic acid (MPA) and its major metabolite MPA-glucuronide (MPAG) in human plasma. Both free MPA and MPAG were isolated from plasma samples using ultrafiltration prior to analysis. Each chromatographic run was completed within 13 min.

Randomized trial of Alemtuzumab for prevention of graft rejection and preservation of renal function after kidney transplantation.

Background: A randomized, multicenter, controlled trial was undertaken to evaluate the safety and efficacy of Alemtuzumab, a powerful lytic agent for both T and B lymphocytes, in the prophylaxis of rejection in renal transplantation (RTx).

Methods: Thirty patients were randomized to receive Alemtuzumab together with low-dose cyclosporine (CsA) monotherapy (CAMPATH, n = 20) or to full doses of CsA with azathioprine and corticosteroids (Standard, n = 10). CsA was administered at doses to achieve whole-blood trough CsA levels of 90 to 110 ng/mL and 180 to 225 ng/mL in CAMPATH and Standard groups, respectively.

Simple reversed-phase ion-pair liquid chromatography assay for the simultaneous determination of mycophenolic acid and its glucuronide metabolite in human plasma and urine.

A simple and reproducible reversed-phase ion-pair high-performance liquid chromatographic (HPLC) method using isocratic elution with UV absorbance detection is presented for the simultaneous quantitation of mycophenolic acid (MPA) and MPA-glucuronide (MPAG) in human plasma and urine. The sample preparation procedures involved simple protein precipitation for plasma and 10-fold dilution for urine. Each analytical run was completed within 15min, with MPAG and MPA being eluted at 3.

Limited tolerability of levofloxacin and pyrazinamide for multidrug-resistant tuberculosis prophylaxis in a solid organ transplant population.

Study Objective: To determine the long-term tolerability of prophylactic administration of pyrazinamide and levofloxacin in patients possibly exposed to multidrug-resistant tuberculosis (MDRTB) after undergoing solid organ transplantation.

Design: Retrospective analysis.

Setting: Community outpatient clinic.