The document discusses the complex dynamics of pharmaceutical pricing, particularly focusing on value-based differential pricing (VBDP) as a means to achieve static and dynamic efficiency in drug pricing across different countries. It outlines the relationship between VBDP and Ramsey pricing, emphasizing the importance of tailored pricing strategies for various income levels to ensure both fair access and adequate R&D funding. Additionally, it presents examples of differential pricing in both self-pay markets and through initiatives like the GAVI alliance for vaccines.