This position paper from IFPMA addresses substitution relating to biosimilars and their reference products at the retail pharmacy level. While this practice has been in place in many countries for generics, for biosimilars, the practice is only emerging.

Requirements vary, but in general, pharmacy-mediated substitution is allowed only when the patient can expect the same efficacy and side effects following the switch. Furthermore, there should not be any need for additional instruction or supervision of the patient by health care providers or any increased risk to the patient.

Recommendations

The position paper outlines key recommendations:

• A structured science-based framework should be in place for the regulatory evaluation of pharmacy-mediated substitution.
• Pharmacy-mediated substitution for biosimilars should only be granted after an evaluation of the immunogenicity risk concluding that unsupervised switches do not pose an increased risk to patients.
• A switching study demonstrating that repeated switching between the reference product and the biosimilar is not associated with a higher risk than continuous treatment with the reference product should be considered.
• Pharmacy-mediated substitution should only occur for the indications for which the biosimilar is licensed.
• The delivery system and differences in handling following an unsupervised switch should also be evaluated.
• The prescribing physician should have the right to refuse substitution.
• Unless the requirements outlined above have been met, transition of a patient from a reference product to a biosimilar product should be supervised by the treating healthcare provider.