Renflexis is a Remicade biosimilar recently approved by the FDA. But, what is a biosimilar?
Infliximab is the generic name of Remicade. The medication is a biologic immunosuppressant that works by binding to tumor necrosis factor alpha (TNF-α), a chemical messenger known to play a key role in the autoimmune response. Renflexis is known by the generic name: infliximab-abda. The biosimilar name is different because biosimilar medications are not true duplicates of the original drug.
Remicade was originally licensed and approved as a biosimilar by the FDA in 1998. This is important because a product that is classified as a biosimilar has different patent and exclusivity protections as compared to traditional drugs.
Patents, exclusivity, and biosimilars
Patents and exclusivity timetables in drug development are complicated but incredibly important to drug developers. To oversimplify: without exclusivity, a company could spend billions of dollars on research and development without having an opportunity to sell the drug at a price to recoup those costs and profit as a business before other companies make nearly identical versions (generic drugs and biologics). Very quickly, you can see how exclusivity could determine everything from research and development goals to medication pricing. And, of course, exclusivity is not the only “lever.” Insurance companies, pharmaceutical benefits managers (PBMs), doctor prescribing habits, and many other factors influence both sides of this equation.
While this isn’t the topic of this piece, there are some excellent sources that can help you better understand the intricacies of the drug development ecosystem:
FDA questions on patents and exclusivity
NPR report on how a drug price is set using Sovaldi, a Hepatitis C drug as an example
Understanding biosimilars
Biosimilars are essentially generic versions of medications that can be made and sold when when the patents are up. Traditionally, this is an opportunity for generic pharmaceutical companies to replicate the molecule that has been approved by the FDA. Generic drugs, for example: ibuprofen or ciproflaxacin, are chemically identical to the original medications in “dosage form, safety, strength, route of administration, quality, performance characteristics and intended use.” Because the companies making generic medications do not have the high R&D costs, they can sell the products at a lower cost.
This process is similar, but not identical, for biologic medications. Biologics are derived from living sources, including humans, animals, microorganisms, bacteria, yeast, and more. These complex medications are more difficult to characterize as compared to simple medications. Because of this, the FDA allows for some variability in biosimilars. The result is an FDA-approved medication that has, “no clinically meaningful differences in terms of safety, purity, and potency from the reference product.“
Biologics, like all medications, are only approved for a particular set of conditions or indications. Since Remicade was originally approved for treatment of Crohn’s disease and rheumatoid arthritis (RA), Renflexis and subsequent biosimilars will also only be approved for pre-approved conditions.
Getting the biosimilar Renflexis for RA
Currently, there is a 180-day waiting period between the time when a biosimilar is approved and when a company can begin selling the drug. This waiting period is up for review by the United States Supreme Court.
Renflexis is not the first biosimilar of Remicade. Another medication, Inflectra made by Pfizer, has also been approved. This influx of biosimilars may be great for pricing of drugs as the competition should work to bring prices down.
It is important to note that Renflexis and biosimilars come with many of the same warnings and side effects as the original products. The most common adverse reactions are:
- infections (upper respiratory, sinusitis, and pharyngitis)
- infusion-related reactions
- headaches
- abdominal pain