What the article fails to mention is the costs associated with bureaucratic policies, regulations, licensing, and regulatory expenses to bring a drug to market in the US and in other countries. Not defending the manufacturer's or anything ... but if they didn't have to jump through YEARS AND YEARS of regulatory bs, that would cut costs right off the top.
Then add in the mandated test trials. Successful trials cost ... and failed trials cost a whole lot more. Meanwhile, the manufacturer hasn't actually re-couped their costs since they started years before.
Then the costs associated with patents?!!? That's adds an entire level to the cost to bring it to market.
Next, add the "discounts" that big pharma negotiates to countries to "cut them a deal" so they don't just knock-off the patented formula. The US patients end up paying the difference for those pills/pens as well.