The FDA recently achieved two significant firsts in one approval. On April 21, the FDA licensed infliximab-abda (Renflexis; Samsung) for marketing. While this product represents the fifth biosimilar approved in the United States, it is the first one licensed without the FDA conducting an advisory committee hearing prior to final endorsement. It is also the first time that a second biosimilar was approved for the same reference product infliximab (Remicade; Janssen Biotech). Ideally, both of these occurrences will become more of a routine matter as the market for biosimilars continues to mature.
Like infliximab-dyyb (Inflectra; Celltrion), infliximab-abda is approved for seven of the eight indications for which originator infliximab is licensed, including rheumatoid arthritis, plaque psoriasis, Crohn’s disease in both adults and pediatric patients, ulcerative colitis in adults, ankylosing spondylitis and psoriatic arthritis. The only indication missing is for pediatric ulcerative colitis, which has orphan drug exclusivity until September 2018.
This additional version of the infliximab molecule possesses the devoid of meaning four letter suffix, like all previously approved biosimilars. While not yet enforced, the FDA has stated that originator biologics will ultimately possess suffixes as well. As a result, health care organizations and providers need to assess how biologic drugs will be identified and distinguished throughout the order entry, inventory management, documentation and outcome monitoring processes.
In the health system environment, the non-proprietary (i.e., generic name) is used quite extensively as compared to reliance on brand identifiers. However, the novelty of the biologic suffix coupled with our limited familiarity of biosimilars could create additional confusion. Therefore, should health care organizations differentiate products using both the brand and non-proprietary names? These are some of the operational elements pharmacy should evaluate as the market continues to mature.
Although officially approved, the launch of Renflexis cannot occur until the end of October due to the current interpretation of the 180-day notification requirement. However, this precedent is one of the two issues at the heart of the Amgen v. Sandoz case that will be heard by the U. S. Supreme Court on Wednesday, April 26. If the Supreme Court were to reverse the existing interpretation, with a ruling likely to come by early July, the launch date for Renflexis could be accelerated.
The approval of infliximab-abda and the Supreme Court hearing are only two events that signify the advancement of the biosimilar market after many years of delay and waiting. For example, the FDA recently announced that it will hold an Oncology Drug Advisory Committee meeting on May 25 to review the application for a biosimilar version of epoetin. In addition, up to five more biosimilar applications have potential approval dates before the end of 2017. Pharmacists and other clinicians should use this intervening time where additional products are pending and legal issues are working towards resolution to familiarize themselves and their prescribing colleagues on the nuances of biologic manufacturing and approval.
Regardless of patent litigation and actual timing of launch, each biosimilar approval is an occasion to review the basic precepts of recombinant drug manufacturing, including the inherent variability of all biologics, the capacity of analytical characterization to substantiate similarity between molecules and the processes for medication approval. In doing so, pharmacists and other clinicians can establish the foundation of biosimilar safety and efficacy so future discussions concerning formulary management can focus on the enhanced value competition in the biologic market brings to health care organizations and most importantly, patients.
