Biological treatment

1. Big picture

Biological treatment means using engineered proteins, usually monoclonal antibodies or receptor-fusion proteins, to target a specific immune pathway. Unlike corticosteroids or classic immunosuppressants, biologics are selective: they block one cytokine, receptor, immune cell, complement component, or co-stimulatory signal.

Exam core idea:

Conventional DMARDs = broad immune modulation
Steroids = fast anti-inflammatory rescue
Biologics = targeted immune pathway blockade

Biologics are used when disease is moderate–severe, organ-threatening, refractory to conventional treatment, or steroid-dependent.