Biosimilar Drugs: Everyone Wins!

What is a biologic drug?

Biologic drugs are complex, often large, molecules created from living organisms or their cells, like yeast or bacteria. By comparison, conventional drugs are small molecules that are chemically synthesized in a lab. Chemical synthesis is a simple, standardized process that allows large quantities of a drug to be manufactured in a short space of time. Biologic drugs, on the other hand, require very complex, high-tech processes that are specific to each product. 

Biologics have revolutionized the treatment of many diseases, including rheumatoid arthritis, Crohn's disease, psoriasis, diabetes, and some cancers. However, due to the complexity of the manufacturing process, biologic drugs are more expensive than conventional drugs. In 2018, biologic drugs generated costs in the order of $7 billion for public and private prescription drug insurance plans. 

What is a biosimilar drug? What are the similarities and differences between biosimilars and generic drugs?

The medicinal ingredients contained in generic drugs are identical to those in the brand-name reference drug. In other words, they are copies of conventional drugs.

Biosimilar drugs are a highly similar version of a biologic brand-name drug already on the market. Due to the complexity of the manufacturing process and the fact that they are made using living cells, it is impossible to obtain a perfectly identical version of a biologic drug. As a result, the registration process for biosimilars is much more stringent and requires many more studies than for a generic drug. 
When a biosimilar comes to market, its manufacturer must also comply with strict manufacturing standards in order to ensure that every batch of the drug is of the highest quality—the same standards Health Canada requires for all biologic drugs. 

Biosimilars are authorized by Health Canada for the indications listed on the product monograph. Thanks to the stringent standards in place, biosimilar drugs are effective and safe for each of their indications authorized by Health Canada. 

A patent is usually issued when a new drug is developed. Like generic drugs, biosimilars can be released on the market once the patent on the reference biologic drug has expired. 

Why are some biologic drugs no longer reimbursed?

In Canada, starting in 2019, private and public insurers began gradually phasing out the reimbursement of brand-name biologic drugs where a biosimilar was authorized by Health Canada. 

This decision was based on numerous studies showing that biosimilars approved by government regulators are as effective and safe as the brand-name drug, and that switching from a biologic drug to a biosimilar is also effective and safe. In Europe, experience has shown that biosimilars are an excellent treatment option. In many countries in Europe, biosimilars have been widely used for a number of years, and drug safety monitoring has shown that they are no more likely to be associated with adverse side effects than the brand-name drug they replace. 

The transition to biosimilars is also a matter of cost. The use of biologic drugs has been rising steadily in Canada, creating a significant burden on public and private prescription drug plans alike. 

Since the manufacturing technology for biosimilar drugs has already been developed for the reference drug, the makers of biosimilars are able to produce their drugs at a lower cost. Preferential reimbursement of biosimilar drugs therefore allows public and private plans to continue offering their members a product that is as safe and effective as the reference biologic drug, with a view to better managing costs and ensuring the future of these plans. 

Regular follow-up: The key to proper treatment

All drug treatments, including with biologic and biosimilar drugs, require regular follow-up to ensure the treatment is well tolerated and is achieving the treatment goals. Whether you are starting a new treatment or switching to a biosimilar drug mid-treatment, your care team is there to guide you. 

If you have any questions about your prescribed treatment, talk to your pharmacist or one of the professionals on your care team. They will be able to provide answers to your specific situation.

Coverage for biologic drugs and their biosimilars varies from one insurer to another and from one province or territory to another. It is therefore important to check the reimbursement conditions for your drug with your insurer.