Specialty Pharmacy & Biologic Medication Glossary
Definitions of key terms in biologic therapy, specialty pharmacy, and autoimmune disease treatment
This glossary defines terms you may encounter when managing a biologic prescription — from insurance and prior authorization to drug mechanisms and pharmacy processes.
A
Adalimumab
Generic name for Humira. A TNF-alpha inhibitor biologic approved for rheumatoid arthritis, Crohn's disease, psoriasis, and many other autoimmune conditions.
Anti-Drug Antibodies (ADA)
Antibodies the immune system forms against a biologic medication. ADAs can reduce the drug's effectiveness over time. Combining a biologic with methotrexate often reduces ADA formation.
Autoimmune Disease
A condition where the immune system mistakenly attacks the body's own tissues. Examples include rheumatoid arthritis, Crohn's disease, psoriasis, ulcerative colitis, and lupus.
B
Benefits Verification
The process of confirming a patient's insurance coverage for a specific medication, including formulary status, copay, deductible, prior authorization requirements, and step therapy.
Biologic
A complex protein medicine derived from living cells (bacteria, yeast, or mammalian cells) using biotechnology. Biologics target specific parts of the immune system involved in inflammation.
Biosimilar
An FDA-approved biological product demonstrated to be highly similar to an already-approved reference biologic, with no clinically meaningful differences in safety or efficacy.
Black Box Warning
The FDA's most serious warning label, placed in a box at the top of a drug's prescribing information. Several biologics carry black box warnings for serious infections, malignancy, or cardiovascular events.
Bridge Supply
Free medication provided by the manufacturer while insurance prior authorization is pending, preventing a treatment gap.
C
Cold-Chain
A temperature-controlled supply chain that maintains medications within a required temperature range (typically 36°F–46°F for most biologics) from pharmacy to patient.
Copay Card
A manufacturer-sponsored discount card that reduces the out-of-pocket cost of a biologic for commercially insured patients. Cannot be used with Medicare or Medicaid.
Cytokine
A small signaling protein secreted by immune cells that regulates inflammation and immune responses. Many biologics work by blocking specific cytokines (e.g., TNF-alpha, IL-17, IL-23).
D
DMARD
Disease-Modifying Antirheumatic Drug. Medications that treat the underlying causes of inflammation in conditions like RA. DMARDs include methotrexate (conventional) and biologics (biologic DMARDs or bDMARDs).
F
Formulary
A list of prescription drugs covered by a health insurance plan, organized into tiers that determine the patient's cost-sharing (copay or coinsurance).
G
GLP-1 Receptor Agonist
A class of injectable medications (e.g., Ozempic, Wegovy) that mimic the GLP-1 hormone to control blood sugar and reduce appetite. Some are approved for diabetes; others for weight management.
H
Half-Life
The time it takes for the concentration of a drug in the body to decrease by 50%. Most biologics have long half-lives (1–3 weeks), meaning levels remain detectable for weeks after a dose.
I
IL-17
Interleukin-17. A cytokine that drives inflammation in psoriasis, psoriatic arthritis, and ankylosing spondylitis. Blocked by IL-17 inhibitors like Cosentyx (secukinumab) and Bimzelx (bimekizumab).
IL-23
Interleukin-23. A cytokine that activates inflammatory immune pathways in psoriasis, Crohn's disease, and ulcerative colitis. Blocked by IL-23 inhibitors like Skyrizi, Tremfya, Stelara, Ilumya, and Omvoh.
Immunogenicity
The tendency of a biologic to trigger an immune response (anti-drug antibodies) in the patient. High immunogenicity can reduce a biologic's effectiveness over time.
Interchangeable Biosimilar
A biosimilar designated by the FDA as interchangeable with the reference biologic, meaning it may be substituted at the pharmacy level without prescriber intervention.
J
JAK Inhibitor
Janus kinase inhibitor. A class of targeted synthetic DMARDs (oral or injectable) that block JAK enzyme signaling pathways involved in inflammation. Examples: Rinvoq (upadacitinib), Xeljanz (tofacitinib), Sotyktu (deucravacitinib/TYK2 inhibitor).
L
Limited Distribution Drug (LDD)
A specialty medication that can only be dispensed through a select network of specialty pharmacies, often due to complex storage, handling, or safety monitoring requirements.
Low Income Subsidy (LIS)
Also called Medicare Extra Help. A federal program that reduces Medicare Part D prescription drug costs for beneficiaries with limited income and resources.
M
Monoclonal Antibody
A type of biologic engineered to bind specifically to a single target (antigen), such as TNF-alpha, IL-17, or IL-23. Most biologic drugs used in autoimmune disease are monoclonal antibodies.
N
NABP
National Association of Boards of Pharmacy. An organization that accredits pharmacies meeting high standards for safety, quality, and professional practice. BiologicHealthPlus is NABP-accredited.
P
Patient Assistance Program (PAP)
A manufacturer-sponsored program that provides free medication to uninsured or income-eligible patients who cannot afford their medication.
Prior Authorization (PA)
An insurance requirement that a prescriber obtain advance approval before a specific medication will be covered. BiologicHealthPlus handles all prior authorizations at no charge.
S
Specialty Pharmacy
A licensed pharmacy specializing in complex, high-cost medications — including biologics — that provides additional services such as prior authorization, copay assistance, clinical monitoring, and cold-chain delivery.
Step Therapy
An insurance requirement that patients try one or more less expensive medications before coverage is approved for a more expensive medication (such as a biologic).
Subcutaneous Injection
An injection administered into the fatty tissue just beneath the skin. Most self-administered biologics are given this way.
T
TNF-alpha
Tumor Necrosis Factor-alpha. A cytokine that plays a central role in the inflammatory process of many autoimmune conditions. Blocked by TNF inhibitors like Humira, Enbrel, Remicade, Simponi, and Cimzia.
W
WAC
Wholesale Acquisition Cost. The published list price of a drug before any discounts, rebates, or insurance adjustments. The WAC is the starting point for calculating patient costs before copay programs are applied.
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