; (2) by redesignating subparagraphs (A) and (B) as clauses (i) and (ii) and moving such clauses 2 ems to the right; (3) by striking unavailable .—In the case and inserting “ unavailable .— (A) In general Subject to subparagraph (B), in the case ; and (4) by adding at the end the following new subparagraph: (B) Limitation on payment amount for biosimilar biological products during initial period In the case of a biosimilar biological product furnished on or after July 1, 2020, in lieu of applying subparagraph (A) during the initial period described in such subparagraph with respect to the biosimilar biological product, the amount payable under this section for the biosimilar biological product is the lesser of the following: (i) The amount determined under clause (ii) of such subparagraph for the biosimilar biological product. (ii) The amount determined under subsection (b)(1)(B) for the reference biological product. . 502. GAO study and report on average sales price (a) Study (1) In general The Comptroller General of the United States (in this section referred to as the Comptroller General ) shall conduct a study on spending for applicable drugs under part B of title XVIII of the Social Security Act. (2) Applicable drugs defined In this section, the term applicable drugs means drugs and biologicals— (A) for which reimbursement under such part B is based on the average sales price of the drug or biological; and (B) that account for the largest percentage of total spending on drugs and biologicals under such part B (as determined by the Comptroller General, but in no case less than 25 drugs or biologicals). (3) Requirements The study under paragraph (1) shall include an analysis of the following: (A) The extent to which each applicable drug is paid for— (i) under such part B for Medicare beneficiaries