Is PEGylation of Drugs Associated with Hypersensitivity Reactions? An Analysis of the Italian National Spontaneous Adverse Drug Reaction Reporting System

Background and objective Evidence highlights the allergenic potential of PEGylated drugs because of the production of anti-polyethylene glycol immunoglobulins. We investigated the risk of hypersensitivity reactions of PEGylated drugs using the Italian spontaneous adverse drug reaction reporting system database. Methods We selected adverse drug reaction reports attributed to medicinal products containing PEGylated active substances and/or PEGylated liposomes from the Italian Spontaneous Reporting System in the period between its inception and March 2021. As comparators, we extracted adverse drug reaction reports of medicinal products containing the same non-PEGylated active substances and/or non-PEGylated liposomes (or compounds belonging to the same mechanistic class). A descriptive analysis of reports of hypersensitivity reactions was performed. Reporting rates and time to onset of hypersensitivity reactions were also calculated in the period between January 2009 and March 2021. As a measure of disproportionality, we calculated the reporting odds ratio. Results Overall, 3865 adverse drug reaction reports were related to PEGylated medicinal products and 11,961 to their non-PEGylated comparators. Around two-thirds of patients were female and reports mostly concerned patients aged between 46 and 64 years. The frequency of hypersensitivity reactions reporting was higher among PEGylated versus non-PEGylated medicinal products (11.7% vs 9.4%, p