Monoclonal antibodies are used in medicine mostly (but not exclusively) for the treatment of cancer.
Biosimilars are copies of monoclonal antibodies.
The approval process for biosimilars in Europe is unusually strict. Much stricter than the approval process for other generic drugs.
You do not need to worry about biosimilars.
Biosimilars achieve the same clinical result as those that have been achieved already with the initial original drug.
And in Europe, biosimilars are about 50% cheaper than the original drugs, and these original drugs have very high prices.