US FDA calls industry to help address biosimilar interchangeability

The US FDA has reached out to industry for comments on the use of interchangeability data in the submission of biosimilars through the 351(k) pathway.

The document invites drugmakers to comment on the interchangeability data required when submitting biosimilar applications to the US Food and Drug Administration (FDA) and comes a month after Sandoz’s version of Amgen’s Neupogen (filgastrim) was recommended by the Oncologic Drugs Advisory Committee (ODAC).

According to the notice, a submission should include data to show interchangeability between a biosimilar and its reference biologic, allowing such products to “be substituted for the reference product without the intervention of the prescribing health care provide.”

The drugmaker, therefore, needs to demonstrate that its biosimilar “can be expected to produce the same clinical result as the reference product in any given patient,” the guidance says. Furthermore, the safety and diminished efficacy risks when alternating or switching between the biosimilar and the reference product must not be “greater than the risk of using the reference product without such alternation or switch.”

This differs from the need to demonstrate biosimilarity, which is defined in the biosimilar-specific 351(k) pathway as showing that “the biological product is highly similar to the reference product notwithstanding minor differences in clinically inactive components” with no meaningful differences between the two in terms of the safety, purity, and potency of the product.

The FDA suggests interchangeability data should be included either in the application to show biosimilarity or in a supplement to such an application.

Therapeutic equivalence data?

While Sandoz seemed to have its product recommended with relative ease, Cecil Nick - Vice President at contract research organisation (CRO) Parexel – suggested other biosimilars coming up against ODAC may not have such an easy ride.

“Sandoz had a wealth of clinical data and therefore wasn’t necessarily in the position of a typical biosimialr that is currently being developed, and so from that perspective perhaps we will learn more from future ODAC meetings,” he told Biopharma-Reporter.com.

Nick said in Europe some versions of filgastrim have been approved without therapeutic equivalence data but on quality, pk/pd and immunogenicity data alone.

“Sandoz generated therapeutic equivalence trial specifically for the FDA and it was submitted. If it had not been generated, would it still have got approval? That is an unanswered question that we will have to watch this space to see how it will developed.”