Health insurance glossary
Biosimilar and generic substitution
Plain-English definition
A generic drug has the same active ingredient as a brand-name drug. A biosimilar is a biologic drug highly similar to one already authorized in Canada. Many drug plans pay only up to the price of the lower-cost version, a rule often called least-cost alternative, so if you choose the brand-name product you may pay the difference unless your prescriber documents a medical reason.
By the HealthRate editorial desk
How it works
Pharmacists can usually substitute an interchangeable generic unless the prescriber writes that no substitution is allowed.
Biologics are made from living cells, so a biosimilar is highly similar to the original rather than identical; public and private plans set their own rules on when they cover it in place of the original.
If a plan applies a least-cost rule, ask before filling whether the product you were given is the one the plan pays for in full.
Why it matters
The same prescription can cost very different amounts depending on which version is dispensed. Knowing your plan's substitution rule avoids paying a brand-name difference you did not expect.