Detection of lot-to-lot variations in the amorphous microstructure of lyophilized protein formulations

• Published in: International journal of pharmaceutics 2007-08, Vol.340 (1), p.34-41
• Main Authors: Hirakura, Yutaka, Yamaguchi, Hideto, Mizuno, Masayasu, Miyanishi, Hideo, Ueda, Satoshi, Kitamura, Satoshi
• Format: Article
• Language: English
• Subjects: Amorphous; Biological and medical sciences; Calorimetry, Differential Scanning; Chemistry, Pharmaceutical; Chromatography, Gas; Crystallization; Crystallography, X-Ray; Freeze Drying; General pharmacology; Heterogeneity; Humans; Interleukin-11 - chemistry; Lot-to-lot variation; Lyophilized formulation; Medical sciences; Nephelometry and Turbidimetry; Pharmaceutical Solutions - chemistry; Pharmaceutical Solutions - standards; Pharmaceutical technology. Pharmaceutical industry; Pharmacology. Drug treatments; Powder Diffraction; Protein Conformation; Quality Control; Recombinant Proteins - chemistry; Solubility; Technology, Pharmaceutical - methods; Time Factors; TSC; TSDC; Water - chemistry
• ISSN: 0378-5173; 1873-3476
• DOI: 10.1016/j.ijpharm.2007.03.016

Reconstitution of lyophilized protein formulations sometimes results in a cloudy solution, depending on the compositions and manufacturing conditions, which causes quality concerns. In this study, the lyophilized protein formulation of recombinant human Interleukin-11 (rhIL-11) was investigated using different lots with varying dissolution behaviors upon reconstitution due to differing processing conditions. In an attempt to distinguish the solid structures in the different lots, relatively new techniques such as inverse gas chromatography (IGC) and thermally stimulated depolarized current (TSDC) as well as powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) were adopted for analysis. PXRD, DSC, and IGC all failed to distinguish between the solid structures, but TSDC was able to discern the differences. Interestingly, TSDC suggested that the variations in dissolution behavior were attributable to the differences in molecular mobility and the micro heterogeneity of amorphous components in the solid structures. Since even the cloudiest reconstituted solutions became transparent in several minutes, it was likely that the differences in the solid structures of the different lots of lyophilized cakes were slight. This study demonstrates the usefulness of TSDC in the analysis of lot-to-lot variations in amorphous pharmaceuticals.