To amend part D of title XVIII of the Social Security Act to require the Secretary of Health and Human Services to determine, on behalf of Medicare beneficiaries, covered part D drug prices for certain covered part D drugs, and for other purposes.

Medicare Fair Drug Pricing Act of 2018 This bill requires the Centers for Medicare & Medicaid Services (CMS) to negotiate with drug manufacturers in determining the price that may be charged for prescription drugs under the Medicare prescription drug benefit. Under current law, the CMS may not interfere with negotiations between drug manufacturers and prescription drug plan (PDP) sponsors. The bill creates an exception to this prohibition with respect to specified drugs that: (1) are single-source or biological, (2) are not both manufactured by more than two drug manufacturers and manufactured by at least one manufacturer as a generic drug, and (3) meet other specified requirements. The CMS must promulgate regulations regarding the identification of such drugs. With respect to these drugs, the CMS shall negotiate the price that may be charged to PDP sponsors and Medicare Advantage (MA) organizations for Medicare and MA enrollees. The bill establishes processes for negotiation and price determination in the initial plan year and subsequent plan years. A manufacturer must participate in the negotiation process as a condition of coverage under the Medicare prescription drug benefit.