When will there be generic Viagra?

Answer 1

Probably not any time soon. The history of the issue is somewhat complicated. The original patent for sildenafil (the active ingredient in Viarga) was obtained in late 1980s and set to expire in 2012. That original patent did not mention erectile dysfunction because the benefits of sildenafil for that condition were discovered only later.

In the 1990, Pfizer obtained another sildenafil patent covering its use as a drug for erectile dysfunction. That patent is set to expire in 2019. There was an attempt by Teva Pharmaceuticals, a generics makes, to invalidate the later expiring sildenafil patent via a lawsuit.  That attempt has failed and, barring any successful appeals, Viagra's currently valid patent  is set to expire in 2019.

There is a wrinkle to the story, however. Viagra has the same active ingredient (sildenafil) as Pfizer's another drug Revatio used to treat pulmonary arterial hypertension. In fact, that indication was a part of the original sildenafil patent set to expire in 2012. Hence, generic Revatio will be possible after 2012, and it contains the same active ingredient as Viagra. Even though the doses are slightly different, some doctors are expected to prescribe generic Revatio for erectile dysfunction.

The upshot is that a generic drug with the same active ingredient as Viagra (albeit for a different indication and somewhat differently formulated) may enter the market in 2012 even though Viagra patent remains in force until 2019.