Calibration of the human immunoglobulin BRPs for ACA and molecular size (batch 1) and for Fc function and molecular size (batches 1 & 2)

The current European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation batch 3 (BRP3) for Human Immunoglobulin was established in 2005. Stocks of this BRP are dwindling and a replacement batch is needed to serve as working standard in the tests for distribution of molecular size by HPLC, anticomplementary activity (ACA) and Fc function, in accordance with the requirements of the Ph. Eur. monographs Human normal immunoglobulin (0338) and Human normal immunoglobulin for intravenous administration (0918). The European Directorate for the Quality of Medicines & HealthCare (EDQM) carried out a project (BSP099) to establish replacement batches for this BRP. The project was run in 2 phases, a prequalification phase (Phase 1) and an international collaborative study (Phase 2) involving 19 laboratories. Three batches of candidate materials of various sizes, Samples A, B and C, were procured from 2 different manufacturers on the European market. Based on the results of the study, Sample A was shown to be suitable as a reference standard for the ACA test and for molecular size determination by HPLC, whereas Samples B and C were demonstrated to be suitable for the Fc function test and for the molecular size determination by HPLC. All 3 BRPs are to be used in conjunction with the monographs Human normal immunoglobulin (0338) and Human normal immunoglobulin for intravenous administration (0918). The BRPs were adopted by the Ph. Eur. Commission at its 141st session in November 2011 as official Ph. Eur. Human Immunoglobulin BRPs for ACA and molecular size Batch 1 (Sample A) and Fc function and molecular size Batch 1 and Batch 2 (Samples B and C respectively).