Foundational Analysis of the Impact of Mechanical Stress on Molecular Size Distribution in Immune Globulin Intravenous, Human-stwk, 10%

Introduction It is imperative to minimize protein aggregates in commercial intravenous immunoglobulin (IVIG) therapy as they have been implicated in adverse events and can enhance immunogenicity for patients receiving IVIG therapy. Shear stress, agitation, mixing speed, and filtration can impact aggregate formation during the manufacturing process, while shipping conditions and temperature excursions may contribute after manufacturing. A study was conducted to assess the impact of agitation on the molecular size distribution of Alyglo (immune globulin intravenous, human-stwk, 10% [IVIG-stwk 10%]). Methods 10 mL of IVIG-stwk 10% was dispensed into sterile washed vials, which were stoppered and sealed. Vials were then placed on a Green SSeriker shaker (Vision Science), and agitation started at 50 rpm in an upright position at a temperature of between 20 and 25°C to induce mechanical stress. On days 0, 1, 3, and 11, samples were withdrawn and diluted 1:16 with saline for analysis. The molecular size distribution of monomers, dimers, high-molecular weight aggregates, and fragments was quantified using size-exclusion high-performance liquid chromatography (SE-HPLC). For SE-HPLC, chromatographic separations were performed using a size exclusion column (TSKgel G3000SW) using a sample size of 50 mcL and a flow rate of 0.5 mL/min at a detection wavelength of 280 nm. Results The monomer + dimer percentage for IVIG-stwk 10% on day 0 was 99.576%; day 1 99.582%; day 3 99.591%; day 11 99.526%. The percentage of polymers and fragments remained below their respective validated limits of quantitation (0.3% and 0.5%) for each time point. Conclusion Mechanical agitation for up to 11 days shows minimal impact on IVIG-stwk 10% molecular size distribution. A very high percentage of monomers and dimers remained throughout the duration of the study, compared to polymers and fragments below quantifiable limits. Further assessments, more analogous to real-world conditions, along with additional measurements of opacity and particle size across multiple lots to assess variability, are warranted. Tabular data are included as downloadable supplement files.