As a result of biosimilars slow entry into the US market, the FDA is taking proactive measures to ensure the continued growth of the biosimilars market by educating patients and physicians through online resources and information campaigns to encourage more competition and lowered prices of biologics, according to GlobalData, a leading data and analytics company.
Despite the FDA implementing the Biologics Price Competition and Innovation Act (BPCIA) in 2010 to create an abbreviated pathway for biosimilar drug approval, there are only nine biosimilars available on the US market to date and it is estimated that only 3% of spending on biologics may face competition from biosimilars, according to The New England Journal of Medicine.
A superficial detail that presents an educational barrier is the recent biosimilar naming system employed by the FDA. They require the biosimilar to include the non-proprietary name and a suffix that identifies the manufacturer to improve pharmacovigilance, but this results in confusion for physicians and patients who might be led to believe that the clinical effects of the biosimilar differ from the original product.
Antoine Grey, MBiochem, Pharma Analyst at GlobalData, comments: “Without a meaningful drive to educate physicians, biosimilars are likely to be dismissed as less effective than their reference products, therefore the financial incentive for entering the biosimilar market is significantly reduced.”
Another barrier reducing financial incentive is the tendency of pharmacy benefit managers (PBMs) to continue favoring the original product over the biosimilar, despite discounts. This is because the initial discounts on biosimilars of 15–20% are offset by the likely small population of patients being initially moved to the biosimilar.
Grey continues: “As a result, biosimilar sponsors are unable to offer large patient volume-based rebates on their products and PBMs therefore try to limit biosimilar uptake so as to maintain rebate payments.”
On top of lacking financial incentives to use biosimilars, manufacturing a biosimilar that is interchangeable with its reference product is no easy feat.
A biosimilar designated as interchangeable can replace the reference biologic at the pharmacy without the permission of the prescribing physician, but FDA draft guidance from January 2017 means biosimilar manufacturers may have to conduct additional clinical studies to demonstrate that “the risk in terms of safety or diminished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 alteration or switch.”
Owing to the difficulty of conforming to the FDA’s guidance, no biosimilar has yet been designated interchangeable as of April 2018.
The manufacturing process of biosimilars is more expensive and complex compared with generic small molecules, which is relatively straightforward.
Reference product producers tend to be secretive about their manufacturing practices even after patent expiry, delaying biosimilar development. Furthermore, small molecules can be characterised by analysing their end products.
Grery adds: “The process is not as simple for biologics, therefore biosimilar manufacturers may struggle to replicate the reference product even with a sample of the biologic.”