Lack of regulatory clarity dominates US biosimilar debate post Zarxio

The debate about biosimilars in the US has evolved since the launch Zarxio​ (filgrastim-sndz) earlier this month, which demonstrated​ that innovative biologics firms could not stop copycats being sold.

Since then the focus of the discussion has become the outstanding regulatory questions that are likely to shape the nascent US biosimilars market.

CDER Janet Woodcock would have been all too aware of this at a US Senate committee hearing last week when she was grilled about the lack of guidelines on interchangeability and labelling​.

Woodcock’s response was that the US Food and Drug Administration (FDA) is still working on the science and does not expect to release guidelines this year.

Guidance calls​

Industry demand for guidelines is strong with Sandoz, Pfenex and Hospira​ being just three examples of firms waiting for agency clarification.

For example, when asked how it would go about providing a biosimilar candidate is interchangeable, Hospira told us “it's premature to comment since the FDA has not yet released final guidance on the regulatory data requirements for interchangeability​.”

Similarly, Pfenex told us "It is anticipated that companies may have to perform switching studies with the biosimilar and the reference product, but FDA has not provided guidance on the regulatory expectations for the approach. It is expected that interchangeability guidance should be released by end of the year."​

Pricing​

Interchangeability was also identified as a key factor for the US biosimilars market by Francis Megerlin, who is a policy expert from the University’ of California’s Berkeley Center for Health Technology that spoke to us last week.

He said: “Patients treated with interchangeable products are not captive of a given brand. As a consequence, and according to states law that govern substitution, there could be a long-lasting competition for chronic treatments.​”

Megerlin also said “Insurers have an interest to enter and negotiate prices in the most competitive corridor, which would be defined according to the number of products competing, and by state laws that govern substitution​.”

This latter point was echoed by Sandoz’s response to questions about future US biosimilar pricing.  

“Biosimilar pricing will be influenced by a number of factors, such as the therapeutic area and competition in the market​” the firm said, adding “interchangeability could be another factor to consider but without guidance from the FDA on that process it would be premature for Sandoz to speculate on its overall impact​.”