Biosimilars | What is a Biosimilar? | Gastrointestinal Society

Biosimilars | What is a Biosimilar? | Gastrointestinal Society


This video explains innovator biologics and
biosimilars. Biologics are very specific, highly effective
medicines that improve health outcomes in many complex conditions, such as Crohn’s
disease, ulcerative colitis, diabetes, rheumatoid arthritis, cancer, osteoporosis, psoriasis,
HIV, multiple sclerosis, growth deficiencies, and more Biosimilars are products that are similar
to an innovator biologic, but not identical. We’ll come back to that, but first, let’s
cover some background information. We are all familiar with medicines in pill form, known as small molecule; they fill pharmacy shelves. They have simple molecular structures and
each medicine’s formula is relatively simple to produce and copy. Once a patent expires, other companies can
make a copy and sell it as a generic version, which will have the exact same active, chemically-derived ingredient as the innovator. These brands, and their generic copies, are
considered bioequivalent because the generic medications are following the simple chemical
recipe of the innovator drug, providing bioequivalent levels of the drug in the body. Pharmacists often substitute a small molecule
with its generic, as long as there is no specific medical reason to use the brand version. An example of small molecule medicine is acetylsalicylic acid, or ASA, known by its brand name, Aspirin®, but widely available as a generic. By comparison, biologics are very large, intricate
molecules, produced in living cells, from highly specialized ingredients using a complex,
biotechnology process, which is integral to creating the final product. It is impossible to produce an exact copy. An innovator biologic is an original brand
product. Manufacturers must prove the medicine’s
quality, safety, and efficacy and thoroughly document its components and processes. They also conduct numerous clinical trials
treating patients who have the specific diseases for which they seek treatment approval, known
as an indication. Health Canada then approves the product for
each indication for which the manufacturer has submitted solid evidence. The brand has patent protection for a limited
period of time. We have been using biologic medicines for
more than two hundred years, initially in the form of rudimentary vaccines for smallpox
as far back as 1796. Another significant and widely used biologic
medicine came from Canada in 1921, when Drs. Banting and Best extracted the hormone insulin
from pigs for use in humans to treat diabetes, a previously fatal disease. Biologics have diversified into very sophisticated
medicines that continue to significantly improve health outcomes for patients in many disease
areas. Examples of biologics include hormones, blood
products, cytokines, growth factors, vaccines, gene and cellular therapies, fusion proteins,
and monoclonal antibodies. Patients receive biologics by injection or
infusion and cannot take them orally, since the body will inactivate them during digestion. Because biologics are proteins, the body can
develop antibodies to them over time, which can affect how well they work. This immune response, or immunogenicity, might
increase when switching from one biologic to another or back again, and is a strong
reason for a discussion with your health care professional before switching among biologic
products. Now, let’s talk about biosimilars. As with small molecules, once a patent expires,
it is legal for other manufacturers to create a biosimilar. However, in the case of biologics, the innovator
company is not obliged to share its patented manufacturing processes and since there is
inherent variability in a live biological system, an identical copy is not possible
for an innovator biologic or biosimilar. No biosimilar will be deemed identical to
its reference originator biologic. With the biologic recipe’s complexity, biosimilar
drugs are not generic. Health Canada only approves biosimilars for
marketing in Canada when the manufacturer demonstrates that their product is of similar
quality, safety, and efficacy to the original reference drug. However, as with innovator products, minor
differences in production can lead to differences in clinical activity and side effects, which
might not become apparent until the product is in widespread use. There could be many different biosimilars
all referencing one innovator medicine, and each would have different biologic material
and manufacturing processes, similar to the innovator biologic, but not to each other. Health Canada regulates biosimilars as new
drugs by comparison with an innovator reference product previously authorized and marketed
in Canada. Decisions regarding interchangeability and
substitutability of products rest with the various provincial and territorial drug regulatory
bodies. As the federal authority, Health Canada states
that biosimilars are not generic biologics. Health Canada also makes decisions to approve
some biosimilars to treat conditions for which the innovator biologic has approval, through
educated assumptions by extrapolating scientific evidence. This includes a demonstration of comparability
between a biosimilar and its reference biologic with detailed understanding of the drug, the
nature of the disease, and the patient population. Therefore, a biosimilar might have an indication
to treat a specific disease without testing in that disease, and some biosimilars will
not have the full array of indications as the original reference product. The cost of pharmaceuticals, particularly
biologics, is an important consideration as experts look at ways to make pharmaceutical
care sustainable. Because they are complex and have revolutionized
the treatment for many diseases, biologic medicines are costly and consume a large portion
of public and private drug spending. In most cases, biosimilars are less costly
than the original biologic, due to extrapolating scientific evidence performed by the innovator,
which leads to lower development costs for the biosimilar. Treatment options are very important for patients
who have serious health conditions. With appropriate regulations in place around
approval, advertising, and post-market monitoring, as well as private and public insurance coverage,
products that demonstrate a safe and effective track record offer new treatment options for
patients. Biosimilars provide additional, lower-cost
options for patients who are newly-prescribed biologics. Prescribing medicines to treat chronic conditions
should remain a decision between patients and their physicians, and should not occur
for purely financial reasons. On behalf of the Gastrointestinal Society,
I’m Dr. James Gray. For up-to-date information about biologics
and biosimilars in Canada, go to www.badgut.org/biosimilars

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