Well, first the pharma would have to run clinical trials in each...

Well, first the pharma would have to run clinical trials in each of these indications. Trials in the larger indications might cost up to a billion dollars each. It would take years to get to market for each of the indications. Furthermore, some of these very expensive trials would inevitably fail because no drug has clinical trial success in all indications.

If an approved indication was for a larger population (e.g Parkinson’s), reimbursers would not agree to pay orphan drug-type prices. And if a much lower price was set in one indication, the pharma would no longer be able to charge higher prices in any earlier orphan indications.

Multiple generic companies, seeing an opportunity, would likely challenge the patents. If key patents were overturned, which is not uncommon, early generic entry would be allowed. And even if the patent challenges didn’t succeed, some key patents would expire anyway before a large number of indications were approved.

The pharma could also count on having the US government breathing down its neck. Seven years from the date of approval of the very first indication, if the drug is a small molecule and has high sales, the government would list the drug for mandatory price negotiation (i.e. price control).

So, no, I think the pharma would be highly unlikely to be taking over the world with its massive windfall profits.

And on the subject of Aspirin…

Aspirin (acetylsalicylic acid) was first produced and sold in 1899 by Bayer. Who actually was responsible for its development is still a matter of contention, holding true to the saying that success has many fathers, while failure is an orphan.

Within six years the British patent for Aspirin had been overturned. By the time that WWW1 commenced, acetylsalicylic acid was being produced in all major markets, both legally and illegally and the British Government was offering a large reward to anyone who could successfully develop a workable manufacturing process for the drug (a Melbourne pharmacist claimed the prize and subsequently named the tablet “Aspro”.

By the time WW1 ended, the US government had seized all of Bayer’s assets, US patents and trademarks and auctioned them off for $3m. Bayer spent US$1bn buying back the US rights and trademark in 1994. Previous year US sales of Bayer aspirin were US$175m.

So, rather than an example of a company making a "humungous windfall” from developing the world’s most commonly used drug, the story of Bayer and Aspirin, in my view, is actually a cautionary tale about the ever-present threat of patent challenge, IP infringement and government intervention in the pharmaceutical industry.