Eli Lilly and Co. continues to misfire on getting new human medicines approved, but its animal health unit is on a roll.

Elanco, based in Greenfield, has introduced three products in just the last month, two of which come in its fast-growing companion animal (read: pets) business line.

On Monday, Elanco unveiled Trifexis—a monthly chewable tablet for dogs that kills fleas as well as hookworm, roundworm and whipworm. The extra parasite-killing power sets it apart from the flea tablet Comfortis, which Elanco launched in 2007.

Earlier this month, Elanco launched Assurity, a topical flea treatment for cats. And in December, Elanco launched Keto-Test, a strip test for dairy cows in the United States that detects elevated ketone levels, which can lead to lost milk production and impaired reproduction.

Elanco’s sales grew 13 percent last year through the end of September, the most recent data available, putting the unit on pace for revenue of about $1.36 billion in 2010.

Overall, Indianapolis-based Lilly’s revenue grew 6 percent through September of last year, to a total of $16.9 billion. Lilly will announce its 2010 financial results on Jan. 27.

Meanwhile, Lilly’s human medicines keep getting smacked down by U.S. regulators. On Tuesday, staff at the Food and Drug Administration balked at Lilly’s experimental drug to help identify plaque in the brain tied to Alzheimer’s disease, saying it hasn’t been shown to be clinically useful.

A panel of outside medical experts will discuss the drug, known as florbetapir, on Jan. 20 and issue a non-binding recommendation on whether it should be approved for market or not. The FDA is scheduled to make a decision on the drug application by March 17, according to the report.

Lilly acquired florbetapir in December by paying $300 million, and promising up to $500 million more, to Philadelphia-based Avid Radiopharmaceuticals. Avid has proposed to market the drug under the brand name Amyvid for use in patients undergoing PET scans, also known as positron emission tomography.

Also, last week, an FDA advisory panel voted that Lilly's experimental drug Solpura has not shown benefits that outweigh its risks in patients with cystic fibrosis or other digestion impairments. Lilly picked up Solpura last year by acquiring Massachusetts-based Alnara Pharmaceuticals Inc. for $180 million, with as much $200 million in later payments.

Lilly needs new drugs on the market to replace five of its bestsellers that are losing patent protection between 2010 and 2013. Generic copies of those drugs stand to drain Lilly of nearly half its current revenue.