Safety and Effectiveness of Multiple Switching Between Originators and Biosimilars: Literature Review and Status Report on Interchangeability.

To date, numerous biosimilars are available in Europe and the practice of switching between originator and biosimilar or between two different biosimilars has become very widespread. However, multiple switching has not been adequately studied. The aim of this study is to conduct a literature review to assess the effectiveness and safety of multiple switches. All PubMed articles involving multiple switches from originator to biosimilars or between different biosimilars were considered. The relevant data on effectiveness and safety were extracted from these studies and the results were reported through descriptive analysis. Fifteen studies were considered, of which 11 were observational and 4 clinical trials. Inflammatory bowel disease and psoriasis were the most studied diseases. All studies reported that the effectiveness and safety in patients whose treatment involved multiple switches, was comparable to patients whose treatment involved a single or no switch at all. Some therapeutic fields such as oncology and renal insufficiency were not represented at all in the multiple switch studies. New evidence is desperately needed and should be made available to the scientific community and decision-makers.