Your point about R&D is valid, but in this case epi was first synthesized in 1895 and the R&D cost has long since been amortized and the IP is in the public domain.
I agree it's a good business plan as a solo participant in the market, but as a second or third entrant, probably less so-- depending on IP around the formulation and delivery method.
With the number of company with discontinued products in the Orange book, i suspect there is some economic burden.
> i'm not sure why the price will stand in the long term.
I think the system we have leads to partial collusion, since all firms have an incentive to keep prices high and share the market two or three ways. If there were 30 or 40 pharma companies competing it would be a different story.
http://www.patent-invent.com/adrenaline_patent.html
This article suggests that it was in fact a very shrewd business plan:
http://www.bloomberg.com/news/articles/2015-09-23/how-market...