The Safety of Biosimilars

Tracking and tracing the use of all biologics, including biosimilars, enhances patient safety. Where there are multiple companies developing a biosimilar of the same reference molecule, distinct non-proprietary names for each of those biosimilars is fundamental to traceability.

Physicians need complete and accurate data on adverse events linked to a specific treatment to facilitate optimal prescribing for each of their specific patients every time. An infrastructure that supports the ability to track and trace the use of different biologics, including biosimilars, across the entire life cycle — from manufacturing to patient intake to post-treatment follow-up — is required to enable optimal patient safety monitoring.


All biologic medicines, including biosimilars, present at least some risk of an unwanted immune response to the medicine, where the patient reacts against the proteins in the medicine.1 The timely reporting of this and other adverse events is important. Just as important is ensuring that the adverse event is attributed to the correct biologic manufacturer. To manage the risk of adverse events and protect patients, it is important to have pharmacovigilance programs for each biologic, including each biosimilar medicine. Pharmacovigilance programs include procedures that monitor the safety of medicines to detect, assess, understand and prevent future adverse effects or other safety-related issues.

Naming and Traceability

An important tool to track and trace the use of a medicine given to a patient is a distinguishable International Non-proprietary Name (INN) for each medicine, including biosimilars. INNs were developed to facilitate the identification of pharmaceutical substances or active pharmaceutical ingredients. Each INN is a unique name that is globally recognized and is public property.2 If the INN for a biosimilar is the same as that of the reference biologic medicine, a pharmacist may unknowingly and inappropriately substitute one biosimilar for another biosimilar or the reference biologic medicine.3 In such a case, when prescribing a biosimilar medicine, the treating physician may not know precisely which medicine a pharmacist gave to treat the patient and this is critical for understanding any adverse events. The current INN-based tracking and tracing systems for all medicines are mainly suited for pharmaceutical tracking within the payment systems, not necessarily for tracking and tracing of adverse events.4 Biosimilars are complex large molecules and cannot be substituted like generics because biosimilar product quality and integrity (the critical quality attributes) will differ for each manufacturer.5

Amgen, a developer of both originator products and biosimilars, believes prompt identification of medicinal product problems can be enabled by distinguishable non-proprietary names, which will ultimately enhance patient safety.

WHO's position on Distinguishable International Naming Codes

In August 2014, the World Health Organization (WHO) released a draft Biological Qualifier (BQ) proposal to support a globally recognized distinguishable naming scheme for biologics, including biosimilars. According to the proposal, a four-letter code — the BQ — would be added after the INN. BQ codes are intended as unique identifiers of the active substance from a given source/manufacturer and will be useful for regulatory authorities, healthcare providers and patients in appropriately tracing the use of biosimilars. LEARN MORE

Medical societies and patient organizations supporting distinct non-proprietary names for biosimilars7:

  • Alliance for Patient Access 
  • American Academy of Allergy, Asthma & Immunology 
  • American Academy of Dermatology 
  • American Academy of Neurology 
  • American Association of Clinical Endocrinologists 
  • American College of Rheumatology 
  • American Urological Association 
  • Association of Black Cardiologists, Inc. 
  • Clinical Immunology Society 
  • Coalition of State Rheumatology Organizations 
  • North American Society for Pediatric Gastroenterology, Hepatology and Nutrition
Supported by American College of Rheumatology, the Alliance for Patient Access & others (August 2014)

“…as the name implies and in light of current technology, a biosimilar will only be similar, but not identical to the reference product for the foreseeable future. Distinct nonproprietary names will help to alert physicians that each product, while safe and effective, may differ slightly. Rather than deter physicians from prescribing these products, we believe that allowing physicians to know the exact product that they are prescribing will increase confidence, thus encouraging more robust utilization of biosimilars than may develop without this transparency.”6