Chapter 54: Biologic Response Modifiers & Antirheumatic Drugs

The fundamental principles of BRM action are grounded in the anatomy and physiology of the immune system, specifically distinguishing between humoral immunity, which relies on B lymphocytes and the production of antibodies (immunoglobulins), and cell-mediated immunity, carried out by T lymphocytes (T-helper, T-suppressor, and cytotoxic T cells). BRMs are classified into two main categories: hematopoietic drugs, such as colony-stimulating factors (e.g., filgrastim), which promote the growth and differentiation of bone marrow progenitor cells to boost blood cell counts, often used to counteract chemotherapy-induced bone marrow suppression; and immunomodulating drugs (IMDs). Key IMD subclasses include interferons, multifunctional cytokines with antiviral and antitumour actions; monoclonal antibodies (MAbs), distinguished by the '-mab' suffix, which precisely target foreign antigens or cancer cells; and interleukins (e.g., aldesleukin), which stimulate specialized immune cells like lymphokine-activated killer (LAK) cells, though treatment may be complicated by severe toxicities like capillary leak syndrome. Finally, the chapter details the pathology of rheumatoid arthritis, a chronic autoimmune inflammatory disorder, and the use of Disease-Modifying Antirheumatic Drugs (DMARDs). DMARDs, including conventional options like methotrexate and biological agents such as etanercept, are critical because they slow or arrest the actual disease process, unlike standard anti-inflammatory medications. Regardless of the class, careful nursing management encompassing thorough baseline assessment, monitoring for serious adverse effects (especially infection and bone marrow suppression), and patient education on self-administration and safety precautions is essential for all BRM therapies.