Emerging biosimilars market presents opportunities and challenges

Challenges to a robust market

It is an exciting time for biosimilars, with many approvals and drugs being brought to market in the US in the past several years and more poised to follow suit as patents expire. Yet many challenges remain around the growth of a robust biosimilars market.

Several surveys conducted in recent years have demonstrated suboptimal knowledge of all aspects of biosimilars and highlighted the need for evidence-based education across specialties.^30,31 In response, the FDA recently announced that it was launching an educational campaign to further understanding of biosimilars, including naming conventions (Figure 2).^32,33 Numerous other medical professional societies have produced or are in the process of producing biosimilar guidelines.

Educational outreach by the FDA forms part of their 4-step plan to aid biosimilar development, which also aims to improve the efficiency of biosimilar development and approval, to provide regulatory clarity for manufacturers, to facilitate public understanding and acceptance, and to support a competitive marketplace.

Among the most critical educational gaps is confusion over the issue of interchangeability. Once approved by the FDA, generic drugs are considered interchangeable with the brand name drug and can be substituted at the pharmacy level without referring to the prescribing physician. This is not the case for biosimilars; owing to their more complex nature, biosimilars require a separate designation for interchangeability and none of those approved so far have been given this designation by the FDA.

There has been some confusion about what will be required to demonstrate interchangeability, and the FDA recently produced draft guidance, saying that essentially it should be proven that switching out the reference product for a biosimilar does not increase risk in terms of diminished efficacy or safety. Several companies are beginning to incorporate a switching component into their clinical trials of biosimilars.

Continued postmarketing and real-world studies will also be particularly important for biosimilars to increase confidence in prescribing them by demonstrating their continued efficacy and safety in the long-term. Several real-world studies are now ongoing, including the MONITOR-GCSF trial of filgrastim biosimilars.

Another major barrier to the development of a thriving biosimilars market that achieves the goals of reduced costs and increased access is the financial burden of their development. They are vastly more costly to develop and produce than generics. Added to litigation costs, this can limit their ability to compete in terms of price, which has been reflected in the lower-than-anticipated cost savings with some approved biosimilars thus far.

Experts have suggested that there might be much to learn from the European market, where biosimilars have been available for more than a decade and over time have reached even higher-than-expected savings. With high financial stakes and an increasingly important role in the treatment of cancer, the need to iron out the kinks is more pressing than ever.^7,8,34,35