Interchangeability is an obstacle to the use of biosimilars in the US Posted 27/04/2018

According to Professor Richard Frank from the Department of Health Care Policy, Harvard Medical School, Boston, USA, there are several factors that may account for the slow development of the market for biosimilars in the US [1]. In this article, the issue of interchangeability of biosimilars is discussed.

Designating interchangeability between a biosimilar and its reference drug allows a pharmacist to substitute the biosimilar product for the reference product without involving the prescribing physician. Interchangeability can therefore promote strong price competition, as can be seen by competition between brand-name and generic small-molecule drug products.

The US Food and Drug Administration (FDA) released draft guidance on the interchangeability of biosimilars with their reference biologicals in January 2017 [2]. The comment period on the guidance ended on 19 May 2017 [3]. However, according to Professor Frank, this guidance has ‘created confusion in the industry’.

A demonstration of biosimilarity requires demonstrating that there are no clinical differences in outcome. But to demonstrate interchangeability, FDA requires that the biosimilar ‘can be expected to produce the same clinical result as the reference product in any given patient’ and ‘the risk in terms of safety or diminished efficacy of alternating or switching between use of the biological product and the reference product is not greater than the risk of using the reference product without such alternation or switch’ [4].

The guidance does not go into details about whether this requirement involves meeting an additional standard or producing more data. Conducting additional studies in specific patient populations would be very expensive for biosimilars makers.

FDA is concerned about immune system responses to substitution of biosimilars for reference products. However, regulators in Europe have noted that such risks are very small and in fact Austria is therefore narrowing the distinction between biosimilarity and interchangeability [5].

To date, there are no interchangeable biosimilars on the market in the US. This, according to Professor Frank, is due to the slow development of clear US guidance on interchangeability, which in turn is limiting price competition.

Conflict of interest
Disclosure forms provided by the author [1] are available at NEJM.org.

Related articles
Secrecy is an obstacle to the use of biosimilars in the US

Insurance payment arrangements are an obstacle to biosimilars use in the US

Naming is an obstacle to the use of biosimilars in the US

Obstacles to the use of biosimilars in the US

References
1.  Frank RG. Friction in the path to use of biosimilar drugs. N Engl J Med. 2018;378(9):791-3.
2.  GaBI Online - Generics and Biosimilars Initiative. FDA issues draft guidance on biosimilar interchangeability [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2018 Apr 27]. Available from: www.gabionline.net/Guidelines/FDA-issues-draft-guidance-on-biosimilar-interchangeability
3.  GaBI Online - Generics and Biosimilars Initiative. FDA extends comment period for interchangeability guidance [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2018 Apr 27]. Available from: www.gabionline.net/Guidelines/FDA-extends-comment-period-for-interchangeability-guidance
4.  GaBI Online - Generics and Biosimilars Initiative. Establishing interchangeability for biosimilars in the US [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2018 Apr 27]. Available from: www.gabionline.net/Reports/Establishing-interchangeability-for-biosimilars-in-the-US
5.  Baumgärtel C. Austrian medicines authority positive towards biosimilar interchangeability. Generics and Biosimilars Initiative Journal (GaBI Journal). 2017;6(1):41. doi:10.5639/gabij.2017.0601.009

Permission granted to reproduce for personal and non-commercial use only. All other reproduction, copy or reprinting of all or part of any ‘Content’ found on this website is strictly prohibited without the prior consent of the publisher. Contact the publisher to obtain permission before redistributing.

Copyright – Unless otherwise stated all contents of this website are © 2018 Pro Pharma Communications International. All Rights Reserved.

Comments (0)