https://www.pcisynthesis.com/want-to-know-why-early-drug-development-costs-so-much/ https://www.pcisynthesis.com/want-to-know-why-early-drug-dev... and http:/

https://www.pcisynthesis.com/want-to-know-why-early-drug-development-costs-so-much/ https://www.pcisynthesis.com/want-to-know-why-early-drug-dev... and http://sitn.hms.harvard.edu/flash/2020/modern-drug-discovery-why-is-the-drug-development-pipeline-full-of-expensive-failures/ http://sitn.hms.harvard.edu/flash/2020/modern-drug-discovery... are decent reads. Mostly it's the complexity of the compounds involved, the supply chain, and regulatory costs.