The FDA recently approved Amjevita (adalimumab-atto), Amgen’s adalimumab biosimilar product for seven inflammatory indications in adult patients1. It was the fourth biosimilar approved by the FDA, and was announced just days after approval was granted for Sandoz’s Erelzi (etanercept-szzs), an Enbrel® biosimilar. Both Enbrel® and Humira® are blockbuster drugs with worldwide revenues over $8.7 and $14 billion respectively and the introduction of related biosimilars will certainly impact their growth potential by providing patients with new and different options and greater access to treatments. Further, biosimilars are expected to generate considerable cost savings for patients and reduce the burden on healthcare expenses.
Both Amjevita and Elrezi were approved as biosimilars, not as interchangeable products. What does this distinction mean? There are two types of biological pharmaceutical products - biosimilar and interchangeable. Biosimilars that are FDA approved are highly analogous to an already approved medication, known as the reference product, and have been shown to have no clinically meaningful differences from the reference product. 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. According to the Biologics Price Competition and Innovation Act (BPCIA) of 2010, an interchangeable product may be substituted for the reference product without the intervention of the healthcare provider.
Does interchangeability matter? To a certain extent, yes, as the introduction of a product that delivers the same level of clinical results to a brand name medication will certainly lead to strategic opportunities for the manufacturers. More importantly, an interchangeable biosimilar could make a difference in treating chronic conditions.
Biosimilar manufacturers have incorporated switching designs in their clinical trials in an effort to strengthen their case for interchangeability designation. As with a majority of pharmaceutical products, core to any argument for interchangeable approval and adoption are the economics of the market, including development and revenue potential.
There are several open questions surrounding the designation. Will it lead to questions around the quality and safety of a non-interchangeable biosimilar versus an interchangeable one? Will the status of biosimilar products placed on a formulary be impacted with entry of an interchangeable biosimilar? There will be questions around contracting and pricing, including the matter of whether insurers will use the opportunity to drive down prices.
The lack of guidance for interchangeability has led to a lot of speculation and confusion in the U.S. Results from a recent survey conducted by the Biosimilars Forum and published in Advances in Therapy have indicated knowledge gaps when it comes to biosimilars2. A majority (60 percent) of physicians surveyed understood that interchangeability meant that the biosimilar was considered safe and effective to be switched without resulting in negative outcomes2. A full 80 percent of respondents didn’t realize an interchangeable biosimilar could be swapped in place of a biologic by a pharmacist, and vice versa2.
The FDA announced plans to release the much awaited interchangeability guidance for biosimilars in 2016, but such initial guidance is expected to be delayed until 20173 and the agency has declared that it will not have all of the necessary guidelines completed until 20194. The lack of proper guidelines for interchangeability and biosimilars has been a major concern as members of the medical community, patient groups, and manufacturers assess the opportunities and risks. Until clarity is achieved, physicians are likely to exercise caution in prescribing biosimilars.
In spite of these issues and concerns, biosimilars present a significant market opportunity and will spark competition that could lower prices for branded drugs. Further, the size and expected growth of the U.S. biologics market make it financially attractive for biosimilar manufacturers. The biggest beneficiaries will be patients and taxpayers, as biosimilars are expected to generate significant cost savings. Physicians report being open to switching patients to a biosimilar. In all, as we await regulatory appraisal and guidance, and as manufacturers consider how best to manage their portfolio of brand name products, the pharmaceutical and medical community is aligned to adopt this new category of medication. Another example of the constant state of disruption in the pharmaceutical marketplace.