OBJECTIVES: Branded biologics will soon begin to face competition from incoming biosimilar monoclonal antibodies (mAbs), with many currently in development. Given the transition many markets are making towards becoming increasingly cost conscious, we sought to investigate how budget holders across the most important European markets perceived the incoming oncology biosimilar mAbs. METHODS: The research was conducted through in-depth interviews and focus groups with budget holders and clinicians across the EU5. RESULTS: All respondents had previous experience evaluating and making decisions on small molecule biosimilars (e.g. filgrastim, EPO). However, there was a lack of experience and knowledge amongst EU5 budget holders with biosimilar mAbs and they were unsure how or by whom they were going to be educated. The originator product was preferred in all attributes tested while costs were cited as the most important driver for encouraging adoption of biosimilar mAbs. Additionally, budget holders across the EU5 were adamant about encouraging automatic substitution (albeit, initially only for new patients), of the originator until enough experience was built up (at least 12 months, 24 months likely). Respondents also suggested that key institutions or regions will make decisions early on while other less resourced centres/regions will adopt their decision.  Conversely, clinicians were apprehensive of biosimilar mAbs and anticipate resisting adoption from the budget holders. However, if discounts approach 30%, physicians are likely to have less influence. CONCLUSIONS: Generally, budget holders and clinicians have differing views on the utility and placement of biosimilars in the clinical pathway. The uptake of which will ultimately depend on geographies, discounts offered and clinician experience. Biosimilars are not going away, however, there are strategies that the originator company can utilise and leverage to delay uptake and maintain strong market share.