CMS's new policy for reimbursement of biosimilars for Medicare Part D drugs won't be a de facto path to interchangeability. But it could make the debate over interchangeability irrelevant because it will allow payers and pharmacy benefit managers to use familiar tools like excluded drugs lists to kick the reference drug off formularies if it means getting a better deal on the biosimilar.
On March 31, CMS issued biosimilar reimbursement coverage memos to plan sponsors outlining its requirements for Medicare parts B and D drugs as well as for state Medicaid agencies. The guidance came three weeks after FDA approved the first biosimilar, Zarxio filgrastim-sndz from the Sandoz unit of Novartis AG.
Zarxio is a physician-administered drug, with the majority of prescriptions reimbursed via Medicare Part B. In cases where the biosimilar of human G-CSF is administered in a nursing home or intermediate care facility it would be reimbursed under Part D.
CMS's memo on Part B drugs affirmed what had already been outlined in the Affordable Care Act - physicians will be reimbursed the