The US Biosimilar Pathway: Unclear Just How Abbreviated, But Could Provide Useful Biosimilar 'Stamp'?

From what's known so far, pre-guidelines, about the FDA's as-yet-untested 351(k) biosimilars pathway, it isn't apparently so convincing as to be the obvious choice for all biosimilar applicants. Some sponsors at least feel that the traditional novel biologics approval pathway is just as viable, given uncertainty over the clinical trial burden (which some say may be almost as high as for a BLA) and over how quickly and effectively FDA will respond to 351(k) applications. There has already been a kerfuffle over user fees and how FDA will fund the additional resources required. Also see "Biosimilar User Fee Agreement Reached, But Will Require Appropriations Boost" - Pink Sheet, 22 September, 2011.

As well as in theory allowing interchangeability, the 351(k) pathway would also in theory allow indication extrapolation (for instance if...