How are combination products assigned for review?
Combination products are assigned to a FDA center that will have primary jurisdiction for its premarket review and regulation. Consistent with section 503(g)(1) of the Act, assignment to a center with primary jurisdiction for premarket review and post-market regulation, or a lead center, is based on a determination of the “primary mode of action” (PMOA) of the combination product. For example, if the PMOA of a device-biological combination product is attributable to the biological product, the Agency component responsible for premarket review of that biological product would have primary jurisdiction for the combination product.
Section 503(g) defines primary mode of action as “the single mode of action of a combination product that provides the most important therapeutic action of the combination product” (see also definitions at 21 CFR 3.2. In some cases, the most important therapeutic action cannot be determined. For example, a combination product may have two independent modes of action, neither of which is subordinate to the other. To resolve these types of questions, FDA’s regulations at 21 CFR Part 3 include an algorithm for determining center assignment. The algorithm directs center assignment based on which center regulates combination products raising similar types of safety and effectiveness questions, or, if there is no such center, based on which center has the most expertise to evaluate the most significant safety and effectiveness questions raised by the combination product.
