biologic therapy

Biologic therapy uses laboratory-made antibodies, given by injection, to switch off one precise driver of severe asthma — almost like a sniper shot at a single inflammatory pathway rather than a broad calming of the whole immune system. It is reserved for severe disease that stays uncontrolled despite high-dose inhalers.

Each biologic is engineered to bind and neutralize a specific molecule or cell type in the inflammatory cascade — for example, immunoglobulin E in allergic asthma, or the interleukin-5 and interleukin-4/13 pathways that fuel eosinophilic inflammation. By interrupting one well-chosen step, these drugs can sharply reduce attacks and often let patients cut down on oral steroids. Choosing the right one depends on biomarkers such as blood eosinophil counts and allergy testing.

These treatments are powerful but specialized: they are expensive, given as periodic injections (some can be self-administered at home), and effective only in the patient subtype whose disease is driven by the targeted pathway. They are not a cure, do not replace inhaled controllers, and require specialist assessment to confirm the disease phenotype before starting.