Eli Lilly and Co. can be credited with using acquisitions to unclog its product pipeline. It has launched two drugs in the past 18 months, won market approval for a third, and will likely get nods for two more drugs this year. Trouble is, they all have paltry sales prospects.

The Indianapolis-based drugmaker is desperately trying to gin up new revenue to offset the sales it stands to lose when its bestseller Zyprexa faces generic competitors in October and again when cheaper copies of its No. 2 seller Cymbalta are available in the second half of 2013.

But even when all its recent success are combined, Wall Street analysts estimate, Lilly's sales will be a blip compared to the $10 billion or so the company stands to lose over the next three years.

“Inertia unaddressed,” is how Barclays Capital analyst Tony Butler summed up Lilly’s recent moves after it released 2010 financial results on Jan. 27. Referring to Lilly by its ticker symbol, the analyst added, “LLY’s long-term outlook remains unchanged.”

Lilly’s highly touted blood thinner Effient continues to languish, especially in Europe, where it is already competing against generic copies of the well-established Plavix. Launched in the United States in August 2009, Effient, whose revenue Lilly shares with Japan-based Daiichi Sankyo Co., brought Lilly just $115 million last year.

Some analysts still expect Effient to grow, reaching $800 million or more in sales by 2015. But others have more modest sales projections.

In June 2010, Lilly and Japan-based Kowa Pharmaceuticals Inc. launched Livalo, a very late entrant to the cholesterol-reducing party dominated by Pfizer’s Lipitor and already undercut by multiple generic competitors. Livalo pulled down sales of $6 million last year. And analysts don’t expect it to add much more in the future—even the most optimistic analysts put its sales at no more than $300 million by 2015.

In October, Lilly was dealt another delay from the U.S. Food and Drug Administration on its long-acting diabetes drug Bydureon. Analysts now don't expect Bydureon to receive approval until 2012. Its sales could approach $1 billion by 2015, analysts estimate. But many of those will replace sales of Lilly's short-acting version of the drug, called Byetta, meaning Bydureon will add roughly $500 million in new sales.

In November, Lilly and Australia-based Acrux Ltd. won U.S. market approval for Axiron, an underarm testosterone treatment. Analysts expect it to launch by summer. But they also think the drug will produce only about $300 million in revenue by 2015.

Lilly’s acquisition last year of New Jersey-based Avid Radiopharmaceuticals Inc. gave it access to florbetapir, an imaging agent that could help doctors definitively diagnose patients with Alzheimer’s disease. An advisory panel to the U.S. Food and Drug Administration unanimously recommended the drug last month, if Lilly develops a training program for doctors.

Still, florbetapir sales prospects are so limited, most analysts don’t even have a specific forecast. Jami Rubin of Goldman Sachs Group thinks the drug will launch this year and ramp up to $50 million in revenue by 2015.

Last, Lilly in January touted a partnership with Germany-based Boehringer Ingelheim, in which the two companies will co-promote linagliptin, an oral anti-diabetes drug. But again, the drug will be the third player in its market, and analysts think its sales will produce only about $300 million for Lilly by 2015.

“The potential upside of the deal is limited in our view and does not significantly change LLY’s outlook,” Deutche Bank Securities analyst Barbara Ryan wrote about the deal with Boehringer.

Predicting drug sales years out is difficult, and Lilly’s picture could turn out much differently. But at this point, even the most optimistic analysts think the company's recent string of success will produce only about $2.2 billion in revenue toward filling that $10 billion hole.

Lilly executives recently have been emphasizing the growth of Lilly’s existing products, especially in international markets, along with its animal health business. And those results have been impressive.

Lilly boosted revenue last year by 5 percent to $23.1 billion. Its profit topped $5.2 billion.

“These results allowed us to deliver attractive earnings growth and a healthy dividend for our shareholders, while still investing in the research and development and business development activities that will enable us to bring the next generation of new medicines to patients," Lilly CEO John Lechleiter said when the company announced its results.