ABSTRACT
The safety of biosimilar products has long been the topic of hot debate and incessantly used as a warning sign by the originator product companies to alert clinicians, public, and other stakeholders as biosimilars began to take roots in Europe and in the United States. The immune response may have more or less serious consequences, from a simple tolerance reaction to antibodies, up to therapeutic inefficiency when the antibodies are neutralizing. Immunogenicity is well established that repeated injection of even native human proteins can result in a break in immune tolerance to self antigens in some patients leading to a humoral response against the protein that is enhanced when the protein is aggregated or partially denatured. Biosimilar product developers need to challenge preclinical testing for all products to make this a more accepted practice. While some recombinant products like filgrastim have almost no immunogenicity, other glycosylated products many show a very high level of immune response-triggering ability.
