What happened to Viagra after Pfizer's patent for the 'wonder pill' expired

Initially used to treat high-blood pressure, Viagra was introduced to the erectile dysfunction market in the late 1990s. It has averaged sales of over a billion dollars each year. However, in late 2017, parent company Pfizer lost exclusive rights to Viagra, opening the door to a flood of generics.
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Sat, May 11 20198:00 AM EST