The US Food and Drug Administration has released a proposal for naming biosimilars – lower-cost biotech drugs – almost simultaneously with the market launch of the first such product to be approved by the health watchdog.

The agency will take comments from the public for 60 days before beginning to finalize the proposal.

Given the FDA green light in March of this year, Sandoz’ Zarxio/Zarzio (filgrastim-sndz) is to be launched in the US on Sept. 1 as a cheaper alternative to Amgen's Neupogen (filgrastim), a blockbuster drug used to boost blood cells in certain cancer patients.

Under the FDA’s proposal, all biosimilars would be labeled with a four-letter code to help doctors distinguish the generic product from the original. In the past, ethical drugmakers have stressed that there are safety risks in a switch to an alternate version, which they note may not be a perfect match.

Designed mainly to help doctors and pharmacists avoid accidentally switching patients between drugs, the codes – for example, “drug-cznm" for the original and "drug-hixf” for the biosimilar version – would not have any meaning.

Biosimilars have been available in Europe since 2006, with some 20 products having been approved. In the US by contrast, regulation has been slow in coming. Despite a 2010 provision in the Affordable Care Act (Obamacare) the FDA has needed additional time to develop an implementation system.

Biological generics still represent only a small part of the global drug market. Pharmaceutical consulting firm IMS Health estimates they will account for only 4-10% of the global $250 billion market for biologics by 2020.