Affordable Prescriptions for Patients Through Promoting Competition Act of 2019 This bill prohibits, subject to certain exceptions, the practice of product hopping, which is presumed when a drug manufacturer obtains removal of a drug from the Food and Drug Administration's approved drug list, discontinues a drug, or markets a reformulation of an already approved drug during a certain period after which the manufacturer has been notified that a competing drug manufacturer has applied for generic drug approval.