Cymbalta, the fifth-largest selling drug in the world, is Eli Lillys best-selling drug with an annual sales of $4.7 billion. The drugs patent expired on Wednesday causing the entry of cheaper generic versions in the US market.
The drug accounted for 22% of Lilly revenue last year. In its recent earnings report, Eli Lilly reported that third quarter US sales of Cymbalta were more than $1 billion, an increase of 15% compared to the same period a year earlier. The company estimates fourth quarter sales will be around $500 million.