Bovine serum--regulatory issues.

For many years users of bovine serum in the manufacture of human and veterinary biological medicinal products have relied upon USDA 9CFR to ensure the viral safety of their serum. Recently, EU regulators have formalised their position by issuing guidelines on the use of bovine serum during manufacture. Additionally, the European Pharmacopoeia has drafted a monograph on bovine serum. There is good harmonisation among the recommendations and requirements although the EU CHMP guideline calls for greater attention to be paid to the potential presence of infectious bovine polyoma virus. The EU guidelines also call for various tests to assess the effect of BVDV antibodies in the detection of BVDV. However, in response to criticisms from serum suppliers and users, the stringency of these recommendations is being relaxed. The overall viral safety of bovine serum should be subject to a risk analysis as infectious virus will invariably be present in some batches of serum but remain undetected. Other factors such as the geographical source of the serum, the efficacy of viral inactivation/removal steps and the ability of specific viruses to grow in the production cells being used, should be taken into consideration.