Biological Agent


Biological Agent, Biologic Agent, Biopharmaceutical, Biotherapeutic Drug, Monoclonal Antibody, Immunosuppressive Biologic Drug, Biosimilar Pharmaceuticals, Biosimilars

  • Definitions
  1. Biologic Agents
    1. Pharmaceutical preparations manufactured within biologic systems (e.g. microorganisms)
    2. Contrast with classical drugs that are chemically synthesized
  2. Biosimilars
    1. Biosimilars are Biologic Agents that are similar to the original or reference Biologic Agent, but not exact duplicates
      1. Biologic Agents are complex, often multi-molecule structures that are difficult to replicate exactly
      2. Manufacturers of Biosimilars are required to show FDA similar efficacy, safety and potency to reference agents
      3. Biosimilars tend to cost up to one third less of the original reference agents
      4. Biosimilars vary in their FDA approved indications due to patents, but would be expected to have similar efficacy as reference drug
      5. Insurance formularies will often stop covering original biologic, replaced least expensive biosimilar
        1. Best to update EMR with the currently prescribed biosimilar to avoid frequent pharmacy call backs
    2. Examples
      1. Neupogen (filgrastim) has 2 Biosimilars (Nivestym, Zarxio)
      2. Remicade (Infliximab) has 2 Biosimilars (Inflectra, Renflexis)
      3. Neulasta (pegfilgrastim) has the biosimilar Fulphila
      4. Humira (Adalimumab) will have 12 Biosimilars in 2023
  • Types
  • Biologic Drug Name Interpretations
  1. Biologic Agent naming conventions have changed over time
    1. Transitioning from an older source system naming (e.g. Xi), to a target system naming (e.g. fung)
    2. Older example: Tras-tu-zu-mab (anti-tumor, humanized mononclonal Antibody)
    3. Newer example: benra-li-zu-mab (immune-targeted, humanized Monoclonal Antibody)
  2. Suffix
    1. Mab: Monoclonal Antibody
    2. Cept: Protein that mimics an Immunoglobulin
  3. Pre-Suffix
    1. U: All human origin
    2. O: Mouse cell origin
    3. Zu: Humanized origin
    4. Xi: Mixed or chimeric (part human and part non-human origin)
  4. Middle, Bridging Syllable
    1. T: Tumor target
    2. So: Bone target
    3. Ci: Circulation target
    4. Gro: Growth factor target
    5. Ba: Bacterial target
    6. Fu: Fungal target
    7. Vi: Virus
    8. Ki: Interleukin target
    9. Li: Immune target
    10. Toxa: Toxin target
  5. References
    1. Nomenclature of monoclonal antibodies (Wikipedia)
  • Types
  • Monoclonal Antibody
  1. Identical antibodies that are synthesized by a single immune cell type
  2. Synthesized in labs to be targeted at disease-specific molecules
    1. Rheumatoid Arthritis
    2. Psoriatic Arthritis
    3. Inflammatory Bowel Disease (Crohn's Disease, Ulcerative Colitis)
    4. Targeted Cancer Therapy
      1. Monoclonal Antibody-Mediated Chemotherapy
      2. Small Molecule Inhibitor-Mediated Chemotherapy
  • Precautions
  1. Screen for chronic infections prior to starting Biologic Agents (risk of activation)
    1. Latent Tuberculosis
    2. Hepatitis B
  2. Update any overdue Vaccines prior to starting Biologic Agents
    1. Live Vaccines (e.g. MMR Vaccine) at least 4 weeks prior to starting biologics
    2. Inactivated Vaccines (e.g. Pneumococcal Vaccine, Shingles Vaccine) are best given at least 2 weeks prior to starting biologics
      1. However, inactivated Vaccines may be given while on Biologic Agents
  3. Most Biologic Agents require home storage at a constant refrigerator Temperature
    1. Most consistent cold Temperatures are near the back wall of the refrigerator, and away from the freezer compartment
    2. Freeze-thaw cycles or warmer Temperatures denature Proteins
      1. Inactivates Biologic Agents (loss of activity and efficacy of the most expensive drugs in the pharmacopeia)
      2. Allergic Reactions (Proteins aggregate when denatured, rendering them immunogenic)
    3. References
      1. Santin (2020) Adv Rheumatol 60(1):30 +PMID: 32460880 [PubMed]
  4. Reduce injection related pain
    1. See Subcutaneous Injection
  5. Perioperative Medication Guidelines
    1. Agents are stopped 1-2 weeks before and resumed 2-4 weeks after major surgery (typically continued for minor procedures)
    2. Consult with orthopedics and rheumatology regarding specific medications and patient risk factors
  6. References
    1. (2023) Presc Lett 30(1)
  • Adverse Effects
  1. Most targeted Biologic Agents (e.g. monoclonal antibodies) have the potential for serious adverse effects
    1. Adverse effects fall in general patterns, but each agent also may have specific side effects
  2. Infectious disease
    1. Live Vaccines are contraindicated
    2. Decreased cellular Immunity
      1. Tuberculosis
      2. Sepsis
      3. Systemic fungal infection
      4. Hepatitis B activation
      5. Progressive Multifocal Leukoencephalopathy or PML (polyoma virus)
      6. Disseminated Herpes Zoster
  3. Neurologic syndromes
    1. Multiple Sclerosis
    2. Seizures
    3. Guillain Barre
  4. Hematologic Effects
    1. Aplastic Anemia or other Pancytopenia
  5. Malignancy
    1. Non-melanoma Skin Cancer (use Sunscreen!)
    2. Lymphoma
  6. Miscellaneous
    1. Pneumonitis
    2. Thyroid disease
  • References
  1. Swadron and Mallon in Herbert (2018) EM:Rap 18(11): 7-8