Biosimilar Guidances Issued

The Food and Drug Administration issued guidances in February that outlines its recommendations for developing and approving biosimilar therapies. The announcement came the same day that FDA officials discussed new user fees for biosimilars and generic drugs at a Congressional hearing. Three separate draft guidances map out the scientific considerations, quality analytical factors, and other regulatory issues for bringing to market new therapeutic proteins that are similar, "but not the same" as a reference product.

The documents describe a step-wise approval pathway, starting with extensive analytical, physico-chemical, and biological characterization data that can demonstrate a high degree of similarity. FDA will evaluate the data and then provide advice to the sponsor on the extent and scope of animal and human testing needed to show biosimilarity. FDA will consider multiple factors in making study determinations, including product complexity, formulation, stability, structure-function relationships, manufacturing process, and clinical experience with the reference product.

Unlike European regulators, FDA decided not to issue guidances for developing biosimilars in different drug product classes. To avoid redundant and unnecessary animal and clinical testing, sponsors will be permitted to use a non-US licensed comparator in certain studies, with appropriate bridging data. Most applications, though, will require some additional clinical trials.

Once FDA determines that a product is biosimilar, the sponsor can opt to demonstrate interchangeability—requiring additional switching studies to show that changing to the new product does not affect safety and efficacy.

FDA expects to be inundated with comments on these proposals and plans a public meeting. Meanwhile, staffers are holding dozens of pre-IND meetings with sponsors and encouraging all prospective biosimilar makers to seek early advice.

More information is available at http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm291232.htm. —Jill Wechsler