(A) In general In the case of a public health emergency under section 319 of the Public Health Service Act, an in vitro clinical test is exempt from the requirements of this subchapter and may be lawfully marketed in accordance with subparagraph (B). (B) Criteria An in vitro clinical test may be lawfully marketed in accordance with the exemption described in subparagraph (A) if such test— (i) is authorized for an emergency use under section 564(b)