Purpose

Analytical methods suitable for intact drug products are often necessary to evaluate the equivalence in physicochemical properties between two drug products (DP) containing the same drug substance (DS), e.g., an innovator biologic drug and its proposed biosimilar. Analytical Ultracentrifugation (AUC) is a biophysics technique applied to the analysis of size and shape of biomolecules. However, the application of AUC to formulated monoclonal antibody (mAb) DP at high concentration has not been reported.

Methods

A sedimentation velocity (SV) AUC procedure with a short-pathlength centerpiece was applied to two marketed rituximab DPs, Rituxan® (US) and Reditux® (India), without any buffer exchange or dilution. Detailed precision analysis was performed.

Results

Highly reproducible sedimentation coefficient values (S) and peak areas were obtained for the dominant (> 84%) monomeric rituximab peak. The minor mAb fragment peaks had large variation in both S values and peak areas (3–12%). The identification of oligomer peaks was only reproducible once the abundance was higher than 2%.

Conclusions

SV-AUC provides an orthogonal characterization tool for protein size distribution, composition and assay, which could be informative for biosimilar drug developers who mostly only have access to formulated mAb. However, AUC needs thorough validation on its accuracy, precision and sensitivity.

中文翻译：

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市售利妥昔单抗药物产品粒度分布的沉降速度分析超离心分析

目的

通常需要适用于完整药品的分析方法来评估包含相同原料药 (DS) 的两种药品 (DP) 之间理化性质的等效性，例如创新生物药物及其提议的生物仿制药。分析超速离心 (AUC) 是一种生物物理学技术，用于分析生物分子的大小和形状。然而，尚未报道将 AUC 应用于配制的高浓度单克隆抗体 (mAb) DP。

方法

对两种市售的利妥昔单抗 DP，Rituxan®（美国）和 Reditux®（印度）应用具有短路径长度中心件的沉降速度 (SV) AUC 程序，无需任何缓冲液交换或稀释。进行了详细的精度分析。

结果

获得了主要 (> 84%) 单体利妥昔单抗峰的高度可重现的沉降系数值 (S) 和峰面积。较小的 mAb 片段峰在 S 值和峰面积 (3–12%) 上都有很大的变化。低聚物峰的鉴定只有在丰度高于 2% 时才能重现。

结论

SV-AUC 为蛋白质大小分布、组成和分析提供了一种正交表征工具，这可为大多数只能获得配方 mAb 的生物类似药开发人员提供信息。但是，AUC 需要对其准确性、精确度和灵敏度进行彻底验证。