Phair Relief Act of 2019 This bill establishes and otherwise modifies requirements for pharmacy benefit managers (PBMs), particularly with respect to the disclosure of certain drug pricing information. Among other things, the bill (1) requires PBMs to pass on a minimum percentage of negotiated rebates, discounts, or price concessions to plan sponsors; (2) temporarily requires negotiated prices for covered drugs under the Medicare prescription drug benefit to be provided at the point-of-sale; and (3) requires the Centers for Medicare & Medicaid Services to establish certain quality measures for determining pharmacy incentive payments.