A Primer on Biologics for the Primary Care Physician
Biologic therapies, including monoclonal antibodies (mAbs), receptor fusion proteins, and Janus kinase (JAK) inhibitors have transformed the management of inflammatory arthritis and other autoimmune conditions.
In his presentation at the American College of Physicians Internal Medicine Annual Meeting in New Orleans, LA, Col. Matthew B. Carroll, MD, MACP, FACR addressed the expanding use of biologics across specialties, particularly their role in rheumatology and primary care. His presentation set out to answer three main questions:
- What are monoclonal antibodies, and why are they called "biologics"?
- How do biologics target the cytokine profile of rheumatologic, dermatologic, and gastrointestinal illnesses?
- What are the benefits and risks of using biologics?
Dr Carroll, a rheumatologist at the Singing River Health System in Biloxi, MS, reviewed key immunologic concepts, focusing on the adaptive immune system’s role in autoimmunity and the mechanism of action of biologics. The session traced the development of biologics from the hybridoma technique in 1975 through the FDA approval of early agents like muromonab-CD3 and infliximab. Subsequent innovations led to a range of targeted therapies, including anti-TNF agents (adalimumab, infliximab), IL-6 inhibitors (tocilizumab), and fusion proteins (etanercept, abatacept). JAK inhibitors such as tofacitinib and upadacitinib represent newer, orally administered options that inhibit intracellular signaling rather than extracellular targets.
Given the complexity of immune-mediated diseases and the evolution of targeted therapies, primary care clinicians increasingly encounter patients treated with these agents. Understanding the immunologic basis, pharmacologic distinctions, and practical implications of biologic use is critical for collaborative care, especially in vaccination planning, infection management, and perioperative decisions, Carroll noted.
Clinical comparisons were also emphasized, including superior efficacy of mAbs over receptor fusion proteins in granulomatous diseases and uveitis, albeit with a higher risk of tuberculosis reactivation and drug-induced lupus.
As noted in the session’s conclusion, “The last 25 years has seen unprecedented changes in rheumatology. Previously destructive illnesses can now be controlled.”
Reference
Carroll MB. The basics of biologics for the primary care physician: biologic logic. Presented at: American College of Physicians Internal Medicine Annual Meeting in New Orleans, LA. https://annualmeeting.acponline.org/educational-program/scientific-program/scientific-sessions#top. April 3, 2025.