FDA releases interchangeability guidance

In long-anticipated draft guidance on interchangeability of biosimilars, FDA said it will require most biosimilars' sponsors to conduct studies showing that switching between a biosimilar and its reference product poses no greater risk than continuing to use the reference product. The guidance recommended designs for switching studies, as well as integrated trials to show that a compound is both biosimilar to and interchangeable with its reference biologic.

The agency said it will "generally" require switching studies to show interchangeability between any biological products that are dosed more than once. Switching studies should evaluate pharmacokinetic and pharmacodynamic measures as primary endpoints, while also assessing immunogenicity and safety. The agency specified that the studies should include at least three switches between a reference product and proposed biosimilar; the last switch should be a transition to the proposed biosimilar from its reference product...