Objectives: Intravesical BCG therapy remains the first-line prophylactic treatment for recurrences of superficial bladder tumours. However, necessary the safety of this medicinal product, for which a potential risk of complications was demonstrated during development, needs to be evaluated.
Material and methods: Based on spontaneous notifications of adverse events reported according to good pharmacovigilance practice and in the context of a survey conducted jointly with Health Authorities, the authors present an analysis of adverse event notifications received by the manufacturer over a three-year period. A summary of serious adverse events (SAE) was established and hypotheses concerning factors predisposing to these adverse events were discussed. Finally, practice guidelines were formulated.
Results: During this period, 97 SAEs were reported spontaneously, including 12 local SAEs, 12 regional SAEs and 73 systemic SAEs. 46 of the 73 systemic SAEs were suspected to be due to BCG infection, 18 were related to immune disorders and the cause of 9 SAEs could not be determined. Several hypotheses are formulated concerning the circumstances leading to the onset of these SAEs and practice guidelines are proposed.
Conclusion: Pharmacovigilance has allowed a better understanding of the qualitative and quantitative safety of BCG-IT in France. Hypotheses concerning factors predisposing to adverse effects were formulated and practice guidelines were proposed. It is essential to continue this collaboration between practitioners, Health Authorities and the manufacturer to ensure optimal use of this medicinal product.