I led a lot of data and analytics work for pharma companies on clinic trials and the point about complexity is hard to overestimate. A pretty good analogy for bringing a major new drug to market is comparing it to building a new space flight system, individually it might have one less zero on total cost, but that's more of a factor of humans bringing dozens of drugs to market at any one point so there are economies of scale rather than it being any less complex.

Also, the article does a good job of describing one side of clinical trial complexity, finding participants and getting them through the funnel, but there's a whole other source of complexity in clinical trials that mean you need massive global efforts: different global regulators have different criteria for 'approving' clinical trials. An indicative example, the Japanese regulator needs to see evidence that the drug was tested in Japan during a trial. They're one of _many_ national regulators that say that.

So even if you _could_ find all a trials participants in one country you likely wouldn't be able to get it approved by many national regulators.

There are 100% valid epidemiological reasons, but often these differing national rules are there for policy purposes outside of drug safety, for example, if you mandate trials need to take place in your country it provides a nice investment in biotech for your economy or by creating specific rules as a lever to control cost in your national healthcare system (e.g. NICE in the UK).