On August 28, 2015 the federal Food and Drug Administration (“FDA”) issued two important policies regarding naming biological products, including biosimilars. First, FDA released a notice announcing the availability of draft guidance entitled “Nonproprietary Naming of Biological Products.” The draft guidance highlights FDA’s current thinking on the need for biological products licensed under the Public Health Service Act (“PHS Act”) to bear a nonproprietary name that includes an FDA-designated suffix. The new naming convention will be applicable to biological products previously licensed and newly licensed under the PHS Act. Specifically, the draft guidance proposes that reference biologics and biosimilars will have nonproprietary names that share a core substance name but are distinguished from each other with a unique four-lowercase letter suffix that FDA will assign at random, with no meaning attached. For example, the nonproprietary name of a reference product could be bioproduct-dkmy and a biosimilar of that product could be bioproduct-fzbs. According to FDA, the guidance is meant to clearly identify biological products to improve pharmacovigilance, and for the purpose of safe use, to clearly differentiate among biological products that have not been determined to be interchangeable. With respect to interchangeable biological products, FDA is soliciting comments on whether the nonproprietary name for such a product should include a distinct suffix, or should share the same suffix as its reference product. Comments to the draft guidance are due to FDA on or before October 27, 2015 and can be submitted here. Alongside the draft guidance, FDA issued a proposed rule designating official names for six specific biological products. The names of these products would include distinguishing suffixes composed of four lowercase letters in accordance with the draft guidance. However, FDA indicates that the Agency is also considering, and seeks feedback on, an alternative nonproprietary naming format for biological products in which the suffix attached to the core name would be derived from the name of the license holder listed on the license. Comments to the proposed rule are due to FDA on or before November 12, 2015 and can be submitted here.