The drug: Spiriva
The company: Boehringer Ingelheim
Estimated worldwide sales 2012: $4.49 billion

Boehringer Ingelheim's respiratory drug Spiriva has been around for a decade. And it has been a workhorse for the privately-held German company. Spiriva brought in $4.7 billion last year, IMS Health reports, and it was one of the key drivers of a 6.8% boost in sales in the first half of 2012 for Boehringer.

Spiriva, which will maintain patent protection into 2014, is one go-to treatment for chronic obstructive pulmonary disease, or COPD. It also holds promise as a treatment for asthma, however, which could drive a new revenue stream if it were to win approval.

A recent study bolstered that hope. The company-sponsored study showed the inhaled drug reduced the risk of a severe asthmatic flare-up by 21% when used along with standard treatments. The company hasn't said when it might submit the drug to regulators for consideration as an asthma treatment. Boehringer apparently still sees enough potential the drug because it has 11 final-stage clinical trials being conducted.

For more:
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