Biologics and biosimilars

The hormone insulin was one of the first biologics to be developed. Since the 1980s, it has been possible to produce human insulin with the help of living organisms. There are now over 230 approved biologics in Germany alone. In addition to such as insulin, these include vaccines, antibodies, and blood products like coagulation (clotting) factors. Biologics play an important role in the treatment of autoimmune diseases such as rheumatoid arthritis, as well as in the treatment of cancer. What all of these medicines have in common is the fact that their active ingredients are obtained from biological substances. They may contain cell parts, proteins or genetically engineered organisms.

The production of medicines made from biological substances must be more closely monitored than that of chemical medicines, because they are always subject to natural fluctuations. So each new production unit (batch) of biologics must be proven to be just as effective as the one that was originally approved. This means that manufacturers of biologics must test each new batch to find out whether the medicine is still having the effect that it is supposed to.

What are biosimilars?

Some biologics are now also available as “imitation medicines” called biosimilars. These are almost identical copies of the original active ingredient. They are produced by other companies and are often much cheaper than the original biologic.

The use of imitation products in medicine has been quite normal for some time now. Up until a few years ago, though, these were mostly identical copies of the active substances of chemically produced medicines. These are called generic drugs, or simply “generics.” One example is copies of the original drug “Aspirin.” Its active ingredient acetylsalicylic acid (ASA) is sold by various drug manufacturers at a lower price under different brand names. Usually, generics can’t be sold until the patent protecting the original medicine has expired.

Biosimilars: Similar, but not identical

Some manufacturers of biologics say that it isn’t clear whether the copies are just as effective and safe as their original. But this isn’t true: Tests are done to ensure that there are no significant differences between the biosimilars and the original medicines. They can almost always be exchanged without any concerns.

It’s only possible to make completely identical copies of medicines that are made chemically, not those that are made biologically. Biological substances are complex and can’t be reconstructed one-to-one. The differences between the original and the copy always need to be so small that they don’t affect the effectiveness or the safety of the medicine.

So the manufacturers of biosimilars must prove that their product is similar enough to the original approved biologic drug: It must not be any more different than each new batch of the original medicine.

What tests are done to see whether biosimilars are as effective as the original?

The European Medicines Agency (EMA) centrally governs the admission of pharmaceutical products in Europe. In addition to its effectiveness, the EMA assesses the safety and the quality of each biosimilar before it’s approved. They check for any significant differences between the original products and the biosimilars. The dose and way the medicine is applied must also be the same.

Tests to check the safety of a biosimilar include antibody tests. They are supposed to ensure that patients don’t build up any antibodies to the biological substance, because that could alter its effect. The manufacturer must also continue to monitor the safety of the biosimilar after it has been approved.

Why do biosimilars exist?

When manufacturers develop new medicines, the patent protection guarantees that they can market their product for a limited amount of time without any competition. Medicines are often very expensive during this phase.

Manufacturers of biosimilars don’t have to repeat all of the studies that are needed for the approval of new medicines. This lowers the cost of development. Another reason why biosimilars are sold at a cheaper price is so that they can compete with the original medicines. In this way, they help to lower health care system expenses without creating any disadvantages for patients.

What should you take into consideration when switching to a biosimilar?

Your doctor may suggest switching from an original medicine to a biosimilar. They should then explain to you in depth what biosimilars are. When you talk with the doctor, you can also bring up any worries or concerns that you might have.

Before switching medicines, the doctor will determine whether you have any allergies or intolerances that would be reasons not to use the biosimilar. That is because generics may contain additives that differ from those in the original products. These additives are used to increase the shelf life and stability of the medicine, for instance, but don’t influence its effectiveness.

To be absolutely sure that a biosimilar has the same effect as the original medicine, patients who switch from a biologic to a biosimilar are monitored for a while at first, as they would be if they started taking a completely new medicine. So far, there are no known problems caused by switching to biosimilars, though.

Arzneimittelkommission der deutschen Ärzteschaft (AkdÄ). Empfehlungen der AkdÄ zur Behandlung mit Biosimilars. October 2017.

Bundesministerium der Justiz und für Verbraucherschutz (BMJV), Juris. Gesetz über den Verkehr mit Arzneimitteln (Arzneimittelgesetz - AMG). December 12, 2005.

European Commission. What I need to know about Biosimilar Medicines - Information for patients. Consensus Information Document. 2016.

Schwerin A, Stoff H, Wahrig B. Biologics. A History of Agents Made From Living Organisms in the Twentieth Century. New York: Routledge; 2013. (Studies for the Society for the Social History of Medicine; Volume 16).

IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.

Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.

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Created on May 3, 2018
Next planned update: 2022


Institute for Quality and Efficiency in Health Care (IQWiG, Germany)

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