Immunogenicity may be impacted by multiple factors including: 

• A biologic drug’s inherent properties such as its molecular structure, post-translational modifications, degree of similarity to endogenous proteins, and presence of aggregates and impurities
• The product’s formulation and stability
• A patient’s genetic characteristics such as HLA type
• Potential cross-reactivity and increased immune responses due to earlier exposure to similar drugs 
• Concurrent conditions such as autoimmune diseases and whether the patient is immunocompromised or immunosensitive
• Frequency of administration, dosage, and route of administration – subcutaneous and intravenous among others 
• Treatment duration