Dr. Angus WorthingThis month, we sat down with Dr. Angus Worthing (@AngusWorthing) to discuss biosimilars and what patients should know about them.

Dr. Worthing is a practicing rheumatologist in Washington, DC and Chair of the American College of Rheumatology’s Government Affairs Committee. Dr. Worthing has extensive experience and expertise in the area of biosimilars regulation and health policy. Here’s what he had to say.



Q: Let’s start with the basics – what are biosimilars?

A: Biosimilars are a new treatment option for some patients who use biologics. They are created by studying a biologic to figure out how it works and making a new copy that is meant to work the same way. The result is a new drug that is very similar to the old one but not 100 percent identical.

The FDA has currently approved three biosimilars to treat rheumatic diseases. They are Inflectra, Erelzi and Amjevita. All three drugs are approved to treat rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. Erelzi is also approved to treat moderate and severe cases of juvenile arthritis in kids two years of age or older. And Amjevita can be used to treat certain types of juvenile arthritis in kids four years of age and older. More biosimilars are expected to become available over the next few years.

Q: So are biosimilars the same as generic drugs? If not, how are they different?

A: Biosimilars are not the same as generic drugs. Generics are pretty much identical copies of a drug. They contain all the same active ingredients, are chemically the same, and you can expect them to work the exact same way as the original medication. Biosimilars are not exact copies.

The complex structure of a biologic makes it nearly impossible to create an exact copy. For example, a common pain medicine might have just 20 atoms. This makes it easy to follow the same recipe to make an identical drug. A biologic can contain more than 20,000 atoms. It’s also made from a mixture of living cells. This makes it very difficult to make an exact copy. Instead, you get a drug that is highly similar but with very minor differences. This is why the new drug is called a biosimilar and not a generic.

These slight differences could cause the drug to interact with the body’s immune system in a different way from the original biologic. So biosimilars must go through rigorous clinical trials to prove they are safe and effective.

Q: Can my pharmacist substitute my biologic for a biosimilar?

Currently, your doctor must prescribe a biosimilar by name in order for you to receive one. This will likely change if the FDA decides a biosimilar is interchangeable. Interchangeable means the FDA feels there is enough clinical evidence the biosimilar will work exactly like the original biologic in any given patient. Your pharmacist may then be able to substitute a biologic with a biosimilar. That is not happening at the moment because the FDA has not finished creating the requirements to become interchangeable.

Where you live will determine whether your pharmacist will be required to notify you and/or your doctor if they substitute a biosimilar for your biologic. Here at the ACR, we strongly believe that patients and their doctors should be notified immediately when a substitution is made. We also believe that doctors should be able to write “dispense as written” on all prescriptions (including biologics) to prevent substitution. This allows you and your doctor to determine which type of drug is right for your needs.

Most states that have laws on biosimilars require patient notification, but other rules vary. The National Conference of State Legislatures has been tracking laws in different states. This is not an ACR resource, but you may find it helpful.

Q: As a patient, what should I ask my doctor about biosimilars?

A: First, you should keep up-to-date on biosimilars from trusted sources such as the ACR and the FDA. Second, make sure you ask your doctor about his or her views on biosimilars. We’re learning new things every day from data coming out of the FDA and studies from other countries. Also, we aren’t sure how much cheaper biosimilars will be, so ask your insurance company or pharmacist for pricing information.

Finally, it’s important that patients speak up and tell their members of Congress and the White House to make sure the FDA gets the resources it needs to safely and efficiently bring more biosimilars to market. More competition means lower drug costs for patients.

Looking for more information on biosimilars? The ACR’s position statement on biosimilars and the Alliance for Health Reform policy briefing are good places to start. You can also check back on the Simple Tasks blog for updates in the weeks and months to come.