What are biologics?Biotherapies are a class of drugs used to manage Crohn's or colitis that includes biologic and biosimilar medications. A biologic is a drug that is made from living cells. Vaccines, insulin, and monoclonal antibodies are examples of biologics. They have large, complex molecular structures. Some of the biologic medications are engineered to target specific activity in the immune system to treat inflammation. Biosimilars are drugs that are similar, but different than the originator biologic. Show
Inflammation is the body’s normal response to things like injury, infection (e.g., bacteria, viruses), stress, and pain. For reasons not yet understood, sometimes the immune system does not function properly and causes damage to healthy tissue. Biologics stop or reduce inflammation by blocking key cells or chemicals involved in triggering inflammation. In IBD patients, use of biologics blocks inflammation in the gut and allows it to heal. While the treatment of inflammatory bowel disease was traditionally limited to steroids and surgery, the development of biologics has been revolutionary to people with Crohn's disease and ulcerative colitis. These medications also have fewer side effects because they are very specific to their targets and hence, they are less likely to accidentally attack non-target cells in the body. Biologics cannot be taken orally because they are proteins and therefore if swallowed, the body would readily digest it. In order to take biologics, the medication would need to bypass the stomach. As such, they are generally administered under the skin by injection or intravenously by infusion. There are different types of biologics used to treat Crohn’s disease and ulcerative colitis. Anti-TNF BiologicsOne of the signals involved in causing inflammation in people with Crohn’s or colitis is called tumour necrosis factor alpha, or TNF-alpha. At present, most of the biologics available on the market are monoclonal antibodies. These are antibodies that travel around the body looking for a very specific target. Often, that target is the messenger chemical 'TNF'. Biologic medications that block those signals are known as anti-TNF biologics. α4β7 Integrin Blockers Biologics or selective adhesion molecule inhibitors (SAM)These biologic medications block the attachment of white blood cells to tissues, preventing them from entering the lining of the gut and causing inflammation. Antibody to the p40 subunit of IL-12 and IL-23IL-12 and IL-23 are messenger chemicals that recruit white blood cells into the gut to cause inflammation. Anti-p40 medications block the messenger signal of both IL-12 and IL-23 to reduce inflammation. In Canada, biologics can also be used as treatment for many other complex conditions, including arthritis, cancer, osteoporosis, psoriasis, HIV, multiple sclerosis, and more. If you have moderate to severe inflammatory bowel disease (IBD), you should discuss with your physician if biologic therapy is appropriate for you. Back to top How are biologics made?With the use of biotechnology, specific cells isolated from living organisms are given a piece of DNA (gene) that codes for a specific protein. These cells will produce this specific protein in large amounts that can then be harvested and purified to be then used as biologics for patients. Biologics tend to be higher in costs than simple small molecule drugs due to their complex manufacturing, transport, and administration. Manufacturers of biologics tend to offer a wide variety of support to patients, including coordination of injection/infusion services and assistance with reimbursement. Private insurers and public health programs can provide partial or complete financial coverage for biologics, depending on specific eligibility criteria. Back to top Side effects and risks of useEven though biologics are very effective therapies, all medications are associated with risk and benefits. Risks of using biologics may include injection or infusion site reactions, allergic reactions, and infection. Your doctor will work with you to determine proper dosage to help balance your symptoms and potential side effects. There is also the risk that your system develops antibodies against the biologics (anti-drug antibody). Your body sometimes thinks that proteins are infections. If you inject a foreign protein, your immune system could develop antibodies to try to fight this "infection" and in doing so, takes the drug out of the blood circulation very quickly. Anti-TNF therapyAnti-TNF therapies are well-tolerated by the vast majority of people. Still, they do slightly suppress the immune system and thus there is a risk of infection. People with IBD who use biologics are especially tested for tuberculosis and hepatitis B because these are two infections that have been shown to flare up if people who have these infections start using anti-TNFs. You can also have allergic reactions to the injection or infusion when taking these medications. If you have multiple sclerosis, lupus or have had a heart failure, you should not on anti-TNFs because they can worsen these conditions. There is also an ongoing debate about whether anti-TNFs could cause cancer because these biologics are often used in combination with other medications that could cause lymphoma. As such, it remains unclear if the anti-TNFs or the other medications are the culprits. There may also be a slightly higher risk of melanoma (skin cancer) but that risk is very small. Anti-integrin TherapyStudies have not shown any increase in side effects, besides small manifestations like irritation at the site of injection. There were no increase in infection and no data suggesting an increased risk of cancer. Anti-IL 12/23 and antil-IL 23 TherapyStudies have not shown any increase in side effects. Back to top What are biosimilars?As with other medicines, once a patent expires for a biologic, it is legal for other manufacturers to reproduce the drug. Most medicines, such as aspirin, are small molecule products, which mean they have simple molecular structures that are easy to reproduce or copy. By comparison, biologics are very large and have complex molecular structures. It is impossible to produce an exact copy without using the exact same ingredients, the living cell lines, and manufacturing conditions. Therefore, the drug that is produced by another manufacturer can never be considered identical to the initial biologic and is referred to as a ‘biosimilar’ (and not a ‘generic’). Click here for our Biosimilars infographic that explains the difference between biologic and biosimilar drugs. Since biosimilars are not as complex in structure as biologics, they are easier to manufacture and are hence less costly. They also have an equal or similar efficacy and safety as the latter. Yet, biosimilars are not suitable for patients who fail or do not tolerate the reference biologic (original drug). Biosimilars can be introduced to your treatment plan in two ways:
The clinical trials and observational experience of taking biosimilars have so far been largely favorable and a cost-saving exercise for most people. Back to top Regulation of biotherapies in CanadaBecause biosimilars are not identical to originator biologics, Health Canada regulates biosimilars as new drugs and states clearly that biosimilars are not generic biologics. Health Canada only approves biosimilars for marketing in Canada when the manufacturer demonstrates that their product is of highly similar quality, safety, and efficacy (effectiveness) to their reference biologic drug. Health Canada requires that there be no clinically meaningful differences in safety and efficacy. Currently, there are two IBD biosimilars approved by Health Canada, but additional biosimilars are expected in the near future, as the patents for innovator biologics continue to expire. Click here to view our Biosimilars in Canada factsheet that provides expert answers to commonly asked questions about how biologic and biosimilar drugs differ, their safety of use and effectiveness, and non-medical switching in Canada. This pdf is downloadable and printer-friendly. Back to top Medications available in CanadaListed below are biologic and biosimilar drugs approved for
use in people living with Crohn's or colitis in Canada. Indications for the use of biologic medications may vary between the originator biologic and biosimilar drug. Indications for medication use include patient age (adult vs pediatric) and disease type (i.e., Crohn's disease vs ulcerative colitis). Detailed descriptions and product monographs are provided for each drug approved by
Health Canada. Anti-TNF (Tumour Necorsis Factor alpha antagonist)
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