When does the Cialis patent expire?

The patent for Cialis expires in 2017. This drug is prescribed as a treatment for erectile dysfunction. It earned its manufacturer, Eli Lilly and Company, $1.9 billion in 2012.

Cialis differs from other erectile dysfunction drugs on the market. It comes in two versions. One pill is designed to be taken for use on a single day. The other variation, the "weekender" pill, has a 36-hour window of usage. These choices give patients a great deal of freedom and flexibility for sexual intercourse. Cialis is available only as a tablet, although similar drugs from other companies also have chewable and dissolvable formats.