Patients' Access to Treatments Act of 2015
Amends the Public Health Service Act to establish cost-sharing limits for health plans that cover prescription drugs and use a formulary or other tiered cost-sharing structure. Prohibits such a health plan from imposing higher cost-sharing requirements, including co-payment and co-insurance, for specialty drugs than for other prescription drugs in a non-preferred brand drug tier. Applies the non-preferred brand drug tier for which beneficiary cost-sharing is lowest, if a formulary used by the health plan contains more than one non-preferred brand drug tier.