With the authorization of an increasing number of biosimilars, and the prospect of multiple biosimilar switching, biosimilar naming and the importance of this for pharmacovigilance are coming into sharper focus. Authors from around the world considered various biosimilar issues/policies in different countries and regions [1].
Current naming policies for biosimilars are not universal. In Europe, there is a ‘prescription by brand’ policy to distinguish the actual product given to patients and enable pharmacovigilance. On the other hand, the US Food and Drug Administration (FDA) finalized a formal naming policy in which a ‘family name’, consisting in a four- letter suffix, identifies the biosimilar [2].
For biosimilar approval, clinical equivalence studies are required. These are to demonstrate that the biosimilar’s efficacy is within a pre-established range of the innovator. However, there is no uniformity with respect to the strategies to determine equivalence for antitumour necrosis factor (TNF) agents. For example, the infliximab biosimilar CT‑P13 was compared with innovator infliximab in patients with rheumatoid arthritis co-medicated with methotrexate. The European Medicines Agency (EMA) required the 95% confidence intervals for the percentage of patients achieving the American College of Rheumatology (ACR) 20 response to be within an equivalence range of ±15%. However, for the adalimumab biosimilar ABP501, FDA recommended a different strategy for the same patient population. That is, the 90% (not 95%) confidence intervals should be within an equivalence range of ±12%. For the etanercept biosimilar GP2015, the pivotal clinical study was performed in patients with psoriasis. The outcome was PASI 75 and FDA recommended that 95% confidence intervals should be within an equivalence range of ±18%. The consequences of having different equivalence ranges and different patient populations for equivalence studies for anti-TNF agents are currently unknown. The question of whether we can confidently move across indications or diseases will become increasingly important when we enter the world of multi-biosimilars and multiple biosimilar switching.
Interchangeability is the practice of alternating between one medicine and another without significant risk of an adverse health outcome. According to FDA, ‘an interchangeable biological product, in addition to meeting the biosimilarity standard, is expected to produce the same clinical result as the reference product in any given patient, and for a product that is given to a patient more than once, the risk in terms of safety and effectiveness of alternating or switching between the interchangeable and the reference product is not greater than the risk of using the reference product without alternating or switching.’ Data are now required on three switches between products to establish interchangeability. These criteria, however, only apply to the US. Differences exist between regulatory guidelines used in different countries.
At present, the available information on interchangeability deals with switching of the originator to a single biosimilar. However, we do not yet have any clear criteria for multiple biosimilar switching. So, what strategy should we follow, especially when dealing with extrapolated indications? The cost of biosimilar switching also needs to be considered – biosimilar use may mean that patients need more training and medical visits, with associated administrative costs.
The biosimilars debate seems to be refocusing issues that have previously been extensively discussed but that have recently lost impetus, including the role of clinical pharmacology in internal medicine.
Conflict of interest
The authors of the research paper [1] did not provide any conflict of interest statement.
Abstracted by Dr Gilberto Castañeda Hernández, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico.
Related articles
US health insurance CMS outlines biosimilar policy
Biosimilar policies in the UK
References
1. Castañeda-Hernández G, Strohal R, Gonçalves J, et al. Considering biosimilar policy. Considerations Med. 2017;1:19-24.
2. GaBI Online - Generics and Biosimilars Initiative. FDA issues final guidance on naming biologicals [www.gabionline.net]. Mol, Belgium: Pro Pharma Communications International; [cited 2018 Mar 16]. Available from: www.gabionline.net/Guidelines/FDA-issues-final-guidance-on-naming-biologicals
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.
0
Post your comment