CONSIDERATIONS OF POOL SIZE IN THE MANUFACTURE OF PLASMA DERIVATIVES

Background: The pooling of human plasma from many donors for the purpo se of manufacturing therapeutic proteins increases the risk of exposin g recipients of these proteins to pathogens that may contaminate 1 or a few units included in the pool. Study Design and Methods: This risk is estimated for a range of manufacturing scales that would derive mat erial from a varied number of donors and for a number of hypothetical infectious agents that may exist in the donor population over a wide r ange of prevalence. Risk is also calculated both for recipients of sin gle doses of a plasma protein and for those who depend on long-term tr eatment with plasma derivatives. Results: Risk of exposure increases w ith pool size and the prevalence of the agent in question and accumula tes with repeated treatments with material manufactured from different pools. Conclusion: Reducing pool size would at best decrease this ris k in proportion to the reduction in manufacturing scale. However, for individuals requiring repeated or continuous treatments, the risk of e xposure to all but the rarest infectious agents would be only minimall y affected, even by large reductions in manufacturing scale.