rebate period CPI–U
(3) Rebate amount (A) In general For purposes of paragraph (1), the amount specified in this paragraph for a part B rebatable drug assigned to a billing and payment code for a calendar quarter is, subject to subparagraphs (B) and (G) and paragraph (4), the estimated amount equal to the product of— (i) the total number of units determined under subparagraph (B) for the billing and payment code of such drug; and (ii) the amount (if any) by which— (I) the amount equal to— (aa) in the case of a part B rebatable drug described in paragraph (1)(B) of subsection (b), 106 percent of the amount determined under paragraph (4) of such section for such drug during the calendar quarter; or (bb) in the case of a part B rebatable drug described in paragraph (1)(C) of such subsection, the payment amount under such paragraph for such drug during the calendar quarter; exceeds (II) the inflation-adjusted payment amount determined under subparagraph (C) for such part B rebatable drug during the calendar quarter. (B) Total number of units For purposes of subparagraph (A)(i), the total number of units for the billing and payment code with respect to a part B rebatable drug furnished during a calendar quarter described in subparagraph (A) is equal to— (i) the number of units for the billing and payment code of such drug furnished during such calendar quarter, minus (ii) the number of units for such billing and payment code of such drug furnished during such calendar quarter— (I) with respect to which the manufacturer provides a discount under the program under section 256b of this title or a rebate under section 1396r–8 of this title ; or (II) that are packaged into the payment amount for an item or service and are not separately payable. (C) Determination of inflation-adjusted payment amount The inflation-adjusted payment amount determined under this subparagraph for a part B rebatable drug for a calendar quarter is— (i) the payment amount for the billing and payment code for such drug in the payment amount benchmark quarter (as defined in subparagraph (D)); increased by (ii) the percentage by which the rebate period CPI–U (as defined in subparagraph (F)) for the calendar quarter exceeds the benchmark period CPI–U (as defined in subparagraph (E)). (D) Payment amount benchmark quarter The term “payment amount benchmark quarter” means the calendar quarter beginning July 1, 2021 . (E) Benchmark period CPI–U The term “benchmark period CPI–U” means the consumer price index for all urban consumers (United States city average) for January 2021. (F) Rebate period CPI–U The term “rebate period CPI–U” means, with respect to a calendar quarter described in subparagraph (C), the greater of the benchmark period CPI–U and the consumer price index for all urban consumers (United States city average) for the first month of the calendar quarter that is two calendar quarters prior to such described calendar quarter. (G) Reduction or waiver for shortages and severe supply chain disruptions The Secretary shall reduce or waive the amount under subparagraph (A) with respect to a part B rebatable drug and a calendar quarter— (i) in the case of a part B rebatable drug that is described as currently in shortage on the shortage list in effect under section 356e of title 21 at any point during the calendar quarter; or (ii) in the case of a biosimilar biological product, when the Secretary determines there is a severe supply chain disruption during the calendar quarter, such as that caused by a natural disaster or other unique or unexpected event.