Biopharmaceuticals, including products approved as biosimilars, must be clearly defined, identified, and named to ensure accuracy in writing and filling prescriptions (1,2,3,4). The US biosimilars law enacted last year enables the Food and Drug Administration (FDA) to approve abbreviated biosimilar biologics license applications (bBLAs) or 351(k) filings based largely on their sponsors proving structural, composition, and clinical similarities with an approved biologic (reference product), much like generic drug approvals (5). The agency has yet to disclose how it will implement…