Systematic investigation of the effect of lyophilizate collapse on pharmaceutically relevant proteins III: Collapse during storage at elevated temperatures

Characterization of the Physical Stability of a Lyophilized IgG1 mAb after Accelerated Shipping-Like Stress

“…Solution turbidity and subvisible particle concentration increased with increasing storage ( T = 0 < T = 1 month < T = 3 months), especially for the samples stored at 40°C and 55°C. Similar to Schersch et al, we also noticed a color change during storage of the lyophilized protein at higher temperatures in this formulation, which Schersch et al reasonably attributed to the well‐known non‐enzymatic browning (Malliard‐type) reaction between reducing end sugars (potentially due to degraded sucrose) and lysine residues in the protein. The turbidity levels and subvisible particle concentrations are highest for the 24 h shaken samples compared with the intact and 2.5 min shaken samples (Intact ∼ 2.5 min shaking < 24 h shaking).…”

“…In this case, the stability of the proteins in the collapsed lyophilized cakes (collapse due to freeze‐drying) was better than the stability of protein in the storage‐collapsed samples. Overall, the authors concluded that the collapse (freeze‐dried) samples appeared to be more stable than the collapsed (storage) samples …”

“…However, a bell‐shaped relationship between moisture content and physical stability (aggregation) has also been observed, for example, lyophilized recombinant human albumin displayed maximum aggregation at ∼50% moisture content . In terms of the effect of the physical integrity of a freeze‐dried cake on protein stability, it has been shown that when a lyophilized cake of an IgG1 mAb is physically collapsed to different extents by using different amounts of stabilizers and bulking agents during the freeze‐drying process, the mAb can still remain stable in the different preparations . The method of cake collapse, however, either during the freeze‐drying cycle or during storage at elevated temperatures, has been shown to potentially be an important factor in determining protein stability during subsequent storage …”

“…18 A freeze-dried cake's physical structure and moisture level are typically optimized as part of protein lyophilization development because either can potentially affect the extent to which a protein may aggregate in the solid state. 6,[19][20][21] These parameters can be interrelated because changes in residual moisture content may affect not only protein structure, but also the physical integrity of the lyophilized cake itself (i.e., a change from a viscous to a rubbery state where molecular mobility increases 7 ). Some lyophilized protein preparations with high moisture content have shown increased chemical degradation due to increased mobility and the ability of water to participate in chemical reactions.…”

“…24 In terms of the effect of the physical integrity of a freeze-dried cake on protein stability, it has been shown that when a lyophilized cake of an IgG1 mAb is physically collapsed to different extents by using different amounts of stabilizers and bulking agents during the freezedrying process, the mAb can still remain stable in the different preparations. [19][20][21] The method of cake collapse, however, either during the freeze-drying cycle or during storage at elevated temperatures, has been shown to potentially be an important factor in determining protein stability during subsequent storage. 21 The effect of mechanical stress on the stability of lyophilized proteins has not been as widely examined.…”