Biosimilars can provide choices for patients and may provide cost savings; however, their uptake has been slow in the USA, in part due to limited knowledge. To provide additional confidence in US pegfilgrastim biosimilars, this narrative review compared the safety profiles of biosimilar pegfilgrastims, currently approved or filed for approval in the USA, with the EU- and US-approved reference pegfilgrastims. Headache and bone pain were common to biosimilars and reference products and occurred at a similar incidence. Clinical trial data on the safety profiles of biosimilar pegfilgrastims and reference products have demonstrated similarity and comparability, with no unexpected safety outcomes. Overall, the safety profiles of biosimilar pegfilgrastims and reference pegfilgrastims demonstrated a high degree of similarity and comparability.
Keywords: adverse event; biologic; biosimilar; febrile neutropenia; pegfilgrastim; safety.
Pegfilgrastim is a biologic drug (one made in living cells such as bacteria) that is given to some patients being treated for cancer. Pegfilgrastim is prescribed to reduce a patient's risk of infection due to a weakened immune system caused by various chemotherapy treatment plans. A biosimilar is a type of biologic medicine that is highly similar to a US FDA-approved reference biologic, and is often cheaper, making it more widely available to patients. As of March 2023, there are eight pegfilgrastim biosimilars (six approved and two awaiting approval by the FDA). This review compared the side effects for the reference pegfilgrastim with the biosimilar pegfilgrastims. The side effects in general and the side effects from treatment were similar for the reference pegfilgrastim and for the biosimilar pegfilgrastims, with the most common side effects being headache and bone pain. Serious side effects such as allergic reactions or problems with the spleen were very low and were also similar between the reference pegfilgrastim and the biosimilar pegfilgrastims. These results show that the safety of the biosimilar pegfilgrastims was similar to the reference pegfilgrastim, with no unexpected side effects. With comparable safety to their reference product, biosimilars have the potential to improve patient access to more affordable treatment options.