It is well recognized that the cost of Protein A resins is substantial. If a product makes it to marketing approval and manufacturing the high cost is amortized over a large number of purification cycles then the contribution to cost of goods is acceptable. However, a high percentage of clinical projects will fail and the Protein A resin will only be used for a small number of cycles. One way to address this issue is to use a less expensive Protein A resin during early phase clinical trials and subsequently switch to a resin designed for manufacturing if the product makes it through Phase I and II. To avoid an increasing regulatory burden offsetting the potential savings it is important that the resins perform in a very similar way with respect to purification performance.