Generic Viagra market overheated

Nearly 50 kinds of Viagra generics from 28 companies have flooded the market since the Intellectual Property Tribunal ruled last year that Pfizer’s patented rights to use sildenafil, an active ingredient essential to treat erectile dysfunction, had expired. Pfizer claimed its sole use until 2014, but the tribunal declared the end of its exclusivity, citing patent terms.

Amid uphill competit...