Raman spectroscopic characterization of drying-induced structural changes in a therapeutic antibody: correlating structural changes with long-term stability.
We characterized the secondary structure of a therapeutic recombinant humanized monoclonal antibody (rhuMAb), formulated with different concentrations of sucrose, trehalose, and histidine and in solution, lyophilized, and spray-dried states. Quantitative secondary structure estimates were obtained using amide I band Raman spectroscopy and a previously developed spectral deconvolution procedure. On lyophilization or spray drying in the absence of sugar, the antibody underwent significant structural perturbation. The beta-sheet content decreased with corresponding gain in the turn and unordered content. With increasing amount of sucrose or trehalose, the extent of structural perturbation decreased. Eventually, at sugar-to-protein molar ratios of > or =360, almost complete structural preservation was observed. Histidine also protected the antibody against lyophilization-induced structural changes. The extent of structural perturbation immediately after lyophilization or spray drying exhibited good correlation with the rate of aggregation for the antibody during long-term storage under accelerated conditions. The results demonstrate that amide I band Raman spectroscopy could be a quick and reliable way to screen excipients and their concentrations during lyophilized or spray dried formulation development.
Pharmaceutical Research and Development, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA. sanes@gene.com
Samir U
SU
Sane
Rita
R
Wong
Chung C
CC
Hsu
D000911:Antibodies, Monoclonal / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D002850:Chromatography, Gel; D004355:Drug Stability; D005612:Freeze Drying; D006639:Histidine / Q000737:chemistry; D006801:Humans; D019999:Pharmaceutical Solutions; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D013059:Spectrum Analysis, Raman; D013395:Sucrose; D014199:Trehalose / Q000737:chemistry
D000911:Antibodies, Monoclonal; D019999:Pharmaceutical Solutions; D006639:Histidine; D013395:Sucrose; D014199:Trehalose