; that is triggered by a patient who fails to achieve outcomes or measures defined under the terms of such value-based purchasing arrangement during the period for which such agreement is effective. ; and (2) by adding at the end the following new subparagraph: (D) Special rule for certain value-based purchasing arrangements For purposes of subparagraph (A), in determining the average price paid to the manufacturer for a covered outpatient drug that is sold under a value-based purchasing arrangement (as defined in paragraph (12)) that provides that payment for such drug is made in installments over the course of such agreement, such price shall be determined as if the aggregate price per the terms of the agreement was paid in full in the first installment during the rebate period. . (d) Definition of value-Based purchasing arrangement Section 1927(k) of the Social Security Act ( 42 U.S.C. 1396r–8(k) ) shall be amended by adding at the end the following paragraph: (12) Value-Based Purchasing Arrangement The term value-based purchasing arrangement means an arrangement or agreement intended to align pricing or payments to an observed or expected therapeutic or clinical value in a select population and includes— (A) evidence-based measures, which substantially link the cost of a covered outpatient drug to existing evidence of effectiveness and potential value for specific uses of that product