Gripe as we might, consumers understand that price increases do happen. What’s not as easily understood is how the price for something can go from $13.50 one day to $750 the next — especially when it’s a generic drug used to save lives. For decades, Daraprim (pyrimethamine), an anti-parasitic used to treat malaria and toxoplasmosis, had been made by GlaxoSmithKline and sold for as little as $1/tablet until not that long ago. Then in 2010 GSK sold the drug to CorePharma, which began to raise the price. Within a year, revenue from Daraprim jumped nearly ten times even though the...