Development of a purity control strategy for pemetrexed disodium and validation of associated analytical methodology.

Stability-indicating reversed phase HPLC methods have been developed and validated for the determination of 13 potential process and degradation impurities in pemetrexed disodium drug substance (DS) and pemetrexed for injection drug product (DP). This paper describes the development of HPLC-UV impurity methods for drug substance and drug product. Relative response factors (RRF) have been determined using HPLC-UV in tandem with CAD or by NMR detection. Conditions for the generation of system suitability solutions are described and assure adequate chromatographic resolution and peak identification without the need for impurity reference standards. The methods were fully validated and demonstrated to have acceptable specificity, linearity, accuracy, repeatability, intermediate precision, detection/quantitation limit, and robustness.

UW is superior to Celsior and HTK in the protection of human liver endothelial cells against preservation injury.

Celsior solution (CS), a new preservation solution in thoracic organ transplantation, was evaluated for its efficacy in cold preservation of human liver endothelial cells (HLEC) and was compared to University of Wisconsin solution (UW) and histidine-tryptophan-ketoglutarate solution (HTK, Custodiol). HLEC cultures were preserved at 4 degrees C in CS, UW, and HTK, for 2, 6, 12, 24, and 48 hours, with 6 hours of reperfusion. Levels of lactate dehydrogenase (LDH), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and adenosine 5'-triphosphate (ATP) were measured after each interval of ischemia and the respective phase of reperfusion. Preservation injury of HLEC as measured by LDH release, intracellular ATP level, and MTT reduction were overall significantly (P > CS > HTK.

Comparison of Celsior and UW solution in experimental pancreas preservation.

BACKGROUND: The University of Wisconsin solution (UW) is the gold standard for pancreas preservation. Celsior (CEL) was formulated specifically for heart preservation. Recently, experimental and clinical experience has been reported on the application of CEL to abdominal organs. In this animal study, pancreas preservation with CEL was compared with that in UW solution. PATIENTS AND MATERIALS: Heterotopic, allogeneic pancreaticoduodenal transplantation was performed in female Göttingen Minipigs (n = 12 donors, n = 12 recipients). The grafts were flushed and stored for 6 h at 4 degrees C in UW or CEL. The recipients were randomized into two groups receiving either UW (n = 6)- or CEL (n = 6)-preserved grafts with a follow-up of 5 days. Blood flow (laser Doppler), partial oxygen tension, histological changes, endothelin-1 (plasma, immunohistochemistry), lipase, amylase, trypsinogen activation peptide, and C-reactive protein (CRP) were measured. RESULTS: Partial oxygen tension was lower in the CEL group (P < 0.05). However, blood flow did not differ between UW- and CEL-preserved organs. The histomorphologic analysis of the pancreatic grafts revealed significantly less edema in the UW-preserved organs. Serum levels of amylase, lipase, CRP, and TAP taken from the central venous blood were comparable in the two groups, except for higher amylase values 36 h after reperfusion in the CEL group compared to the UW group (P < 0.05). Likewise, TAP taken from the portal venous effluent of the graft was found to be higher in the CEL group than in UW (P < 0.05). Endothelin-1 serum levels rose significantly during reperfusion without differences between the two groups. ET-1 immunohistochemistry revealed increased local ET-1 during reperfusion in all grafts. However, the ET-1 immunostaining in the CEL group was more pronounced than that in the UW group (P < 0.05). CONCLUSIONS: Our results suggest that CEL solution is not as effective in preventing pancreatic ischemia/reperfusion damage as the standard UW solution in experimental pancreas transplantation. Increased ET-1 immunostaining and reduced p(ti)O(2) in the CEL group indicate increased microcirculatory damage in the CEL group.