Nothing much.  FDA regulations are a major hurdle though, and means you&#x27;d need to sell a pretty high volume to break even, but nothing insane.<p>Problem:  You set up shop, you make up a big batch of generic insulin and then...you don&#x27;t sell any, because doctors aren&#x27;t prescribing it.  Why would they?  Most probably haven&#x27;t heard of it, and the ones who have will also know (correctly) that the patented improvements may be minor improvements, but they <i>are</i> improvements.  All you&#x27;ve got to compete on is cost, but the doctors aren&#x27;t paying the cost.  Nor are the majority of their customers; they have insurance.  The minority who are paying the cost directly would probably prefer a cheaper option, but that would require <i>them</i> to hear of it, and it&#x27;s not clear there&#x27;s enough of them to cover your overheads even if they did hear of it, and your generic drug margins don&#x27;t cover the cost of the massive marketing campaign you&#x27;d need; you&#x27;re not selling Viagra here.<p>Your success will rely on getting the big insurers to stop covering the better forms of insulin, or at least stop covering it in the general case.  Which they absolutely should do!  And the second one of them tries the &quot;insulin cartel&quot; will do a little lobbying, and some patient groups will express outrage, and a congressman will start talking about hearings, and the NYT will run an nominally balanced news piece about insurance company greed forcing diabetics onto archaic, inferior forms of insulin, and the insurance company will give up, because hell, they just pass the costs on in the form of premiums; it&#x27;s no skin off their nose.<p>And you&#x27;ll go under.  And the worst part is, there&#x27;s no big conspiracy or villain.  The system is just incredibly screwed up.