; or (2) a dosage form, strength, or route of administration that differs from that of the reference product. . (c) Application The amendments made by subsection (a)(4) to section 351(k)(6) of the Public Health Service Act ( 42 U.S.C. 262(k)(6) ) shall apply only with respect to applications approved under section 351(k) of such Act on or after the date of enactment of this Act. Any period of exclusivity granted under section 351(k)(6) of such Act with respect to an application approved under such section 351(k) before the date of enactment of this Act shall apply in accordance with such section 351(k)(6), as in effect on the day before the date of enactment of this Act.