When Should We Use Biologics in Rhinology

Biologics (also known as biologicals, biological products, or biopharmaceuticals) are a specific group of drugs. The World Health Organization defines a drug as “a substance or product that is used to modify or examine physiological systems or pathological conditions for the benefit of the individual.” In one aspect, the term drug refers to a pure chemical substance that is used in medicine and has a biological activity (bioactive), or it could also be a natural mixture containing a standard amount of active substance of plant or animal origin. Drugs generally have well-defined chemical structures and can often be analyzed to determine their components. Unlike conventional chemically synthesized drugs, biologics are produced or extracted in a living system such as a microorganism, human, plant, or animal and contain glucose, protein, nucleic acid, or a combination thereof, and sometimes living cells or tissues. Biologics are usually composed of large complex molecules and are also created as copies of existing structures such as antibodies or hormones. Biologic drugs are immunogenic, even if they are fully human monoclonal antibodies. Antidrug antibodies may reduce the activity of biologics and/or cause side effects. Additionally, reactions such as cytokine release syndrome, immune complex hypersensitivity, serum disease, autoimmune hemolysis, mast cell activation, and fatal anaphylaxis may also develop.