the UK (42%). Of these, the most frequently utilized endpoints were clinical in the US (62.5%) and both clinical and humanistic (20%, respectively) in the UK. Humanistic outcomes were not mentioned in US-based contracts. 25% of US-based contracts also stipulated components of patient compliance, compared to 1 UK-based contract. Conclusions: In an environment of rising prices, VBCs are becoming a cost containment strategy. However to date, only 61 VBCs were noted in the US and UK over 2 decades, which could be driven by lack of contracts and/or transparency in reporting. The lack of contracts could be driven by the challenges of data collection and analysis, which will likely be mitigated by the development of RWE methods for VBCs. More research and transparency is needed on the structure and successes of VBCs and how RWE can improve VBCs.