What You Need To Know about Biosimilars
Biologics are a relatively new class of drugs used to treat rheumatoid arthritis (RA). They are created with genetically engineered proteins, and were first available in 1999. Biologics have been revolutionary for RA treatment, enabling many to go into remission.
Unfortunately, Biologics are quite expensive. Also, some people with RA do not respond to the ones currently on the market, and some stop responding to a previously effective medication. This is called immunogenicity, a process whereby your immune system finds a way around the medication and the RA returns.
Most drugs are created by chemicals using small molecules, meaning generic alternatives are chemically identical. Biologics are made from living organisms and their molecules are large and delicate, making it impossible to create exact copies. Biosimilars are a sort of “copycat” version of the original biologic drug, similar but not identical.
Although there may be some differences between a biosimilar and the original biologic drug, this should not impact the therapeutic effects of the biosimilar. The FDA requires these drugs to go through a stringent approval process before they are available for use in RA treatment.
The FDA has two biosimilar classifications. In one, the biosimilar is highly similar to a specific biologic (called the reference product), is required to work in the same way, and have no clinically meaningful differences from a particular biologic.
The other classification, called interchangeable, must meet the biosimilarity standard, as well as produce the same clinical results as the drug being used as a reference.
Biosimilars are expected to cost less than Biologics, making them more affordable for individuals and insurers. Being slightly different than the reference drug may have the potential for being a benefit in RA treatment in that they can provide more treatment options. This may increase the number of people who enter remission.
Biosimilars will be less expensive than Biologics, but that doesn’t mean they’ll be cheap. Originally estimated to provide savings of 30-40 percent compared to a biologic, there is now concern that the price will increase, due in part because manufacturers of Biologics have been raising prices of these drugs as patent protection neared expiration.
Because biosimilars have no meaningful differences from Biologics, side effects should be similar. An increased risk of infection is the primary concern. Other side effects may include fatigue, nausea, and biosimilars also have the potential for rare and more serious side effects, just as the Biologics. Talk to your doctor for more information.
The American College of Rheumatology is strongly opposed to switching individuals who are stable on a particular biologic to a biosimilar purely to save money. However, persons who are not yet taking a biologic, or whose biologic is not working, may be good candidates for biosimilars.
Biosimilars will not have unique names. The U.S. will use a four-letter suffix to identify the reference medication. Some rheumatologists fear that this could lead to obstacles in monitoring responses to biosimilars versus Biologics. Biosimilar manufacturers also prefer unique names in order to more accurately track potential adverse events.
When your doctor prescribes a medication, your pharmacist can substitute a cheaper generic drug without notifying you or your doctor. There is concern that this will be applied to biosimilars, which are not identical medications. Currently, half of U.S. states and Puerto Rico allow for pharmacist substitution, although this is controversial.
Biosimilars to treat inflammatory conditions have been available in Europe for several years. Due to a different patent structure, it has only recently been possible to develop cheaper alternatives in the U.S.
So far, the FDA has approved several biosimilars to treat inflammatory conditions in the U.S., although not all are currently available. The manufacturers of the biologic reference medication are attempting to protect their products. Therefore, the availability of biosimilars may be delayed due to patent litigation.