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FDA Invites Open Commentary on Biosimilar Interchangeability

Mar 16, 2017 6:58 pm

(Editors note: Just as this article was published, the FDA pushed back the open commentary period to May 19th; this article has been editted to reflect this change -

In January 2017, the Food and Drug Administration (FDA) released its draft guidance on the issue of interchangeability between biosimilars and originator biologic drugs. (Citation source:

As biosimilars enter the marketplace, there will be safety and economic concerns that need to be negotiated.  With interchangeability, the questions is - under what circumstances is the interchangeabilty of a biosimilar and original reference product effective, safe and reasonable?  

What studies and data are needed to ensure the best outcomes?

Who is capable of making these substitutions? The pharmacist? The prescriber? And what is the role of patient preference in such changes?

The guidance for these changes spelled out by the FDA in this guidance document. But recognize this is a draft guidance document and the FDA has invited input from the public, prescribers and from the pharmaceutical industry on how these guidelines be developed and implemented.

The window for YOUR input is will close on May 19, 2017.  RheumNow encourages you to participate in this exercise and express your opinion.

Here is the FDA site for open commentary:

Your commentary will be publically viewable on  The FDA advises that you be concise in your writing and claims and that a constructive, information-rich comment that clearly communicates and supports its claims is more likely to have an impact.  If you disagree with their proposed guidance, you should suggest an alternative and why. Identifyyour credentials and experience that may distinguish your comments from others.

We would recommend you review the FDA guidance document first -

Next we would recommend you review the RheumNow article on this issue -

Key questions for you to consider in your comments and responses:

  • Once biosimilarity is proven, should validation studies on interchangeability be unilateral (originator to biosimilar) ; bilateral (originator to biosimilar or biosimilar back to originator)
  • Do interchangeabiltiy studies allow for transitioning the patient from existing therapy to its biosimilar or only allow the introduction of a biosimilar to someone naive to the biologic (e.g., "new biologic starts")
  • Should the requirements for drug safety be different for biosimilars that have only been studied in hundreds of patients and not the many thousands studied with the reference product. What should the post-marketing committment look like.
  • Should the safety data for biosimilars be compiled and reported according to the disease indication or combined?
  • Should biosimilars be allowed to provide data and studies that permit and alternative delivery option of the biosimilar; different from that employed with the reference product. For instance should Inflectra be allowed to develop an inhaled method of delivering its biosimilar version of infliximab?
  • What power or role will the pharmacist play in drug substitution and biosimilar interchangeability?
  • What role will frequent or annual insurance carrier and plan changes  have on biologic interchangeability?
The author has no conflicts of interest to disclose related to this subject
The author has received compensation as an advisor or consultant on this subject

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