1. Short title This Act may be cited as the Prescription Drug Rebate Reform Act of 2023 . 2. Cost-sharing with respect to prescription drugs (a) In general Subpart II of part A of title XXVII of the Public Health Service Act ( 42 U.S.C. 300gg–11 et seq. ) is amended by adding at the end the following: 2729A. Cost-sharing with respect to prescription drugs (a) In general A group health plan or health insurance issuer offering group or individual health insurance coverage shall set any coinsurance obligation an enrollee has with respect to a prescription drug covered by the plan or coverage based on the net price of the drug, such that no payment by the enrollee with respect to the drug is based on a percentage of the list price of a drug. (b) Applicability Subsection (a)— (1) shall apply with respect to a prescription drug benefit when the enrollee is required to pay a deductible with respect to such benefits and— (A) has not yet satisfied the deductible under the plan or coverage; or (B) has another coinsurance obligation with respect to such benefits under the plan or coverage; and (2) shall not apply if, with respect to the dispensed quantity of a prescription drug, the net price and list price are the same, or are different by not more than 1 cent. (c) Copayments Nothing in this section prevents a group health plan or health insurance issuer from requiring a copayment for any prescription drug if such copayment is not tied to a percent of the specified cost of the drug. (d) Definitions In this section— (1) the term coinsurance means, with respect to prescription drug coverage under a group health plan or group or individual health insurance coverage, a payment obligation of an enrollee in such health plan or health insurance coverage that is based on a portion or percentage of the specified cost of a prescription drug, which may be up to 100 percent of that cost