Viral safety evaluation of plasma-derived therapeutic products

The viral safety of plasma-derived products, in the U.S., is ensured by a complementary approach consisting of donor screening for high-risk activities or history, donor testing for relevant blood-borne viruses, and the inclusion of viral clearance steps in the manufacturing process. Thus, any manufacturing process for the production of plasma-derived products should be validated for its capacity to clear viruses. This validation is performed by using small-scale laboratory models that mimic the actual manufacturing process with regard to its critical operating parameters and performance characteristics. In addition, there are a number of validation components that are deemed essential for obtaining reliable viral validation data. These include: (i) validation of the small-scale model to establish its relevance to the actual process; (ii) choice of viruses in performing spiking experiments; (iii) reliability and validity of the assays used to determine viral titer in the test articles and (iv) calculation of total log reductions in the validated steps.