Sorry, investors, but GlaxoSmithKline's (NYSE:GSK) Avandia isn't going to make a comeback.

It's not that Glaxo isn't trying. The company ran a large, 4,447-patient trial -- dubbed RECORD -- that it hoped would refute a 2007 meta-analysis by Dr. Steven Nissen, which suggested that Avandia increased the risk of heart attacks by 43%. According to results of the trial presented at the American Diabetes Association meeting on Friday, the drug doesn't increase the cardiovascular risk compared to other diabetes drugs. 

But the damage is already done:





Sales of Avandia-containing products (in millions)




Year-over-year increase/(decrease)




There are a couple of reasons why the Avandia franchise will never get back to its $3 billion-a-year heyday. First, while Glaxo will try to get the new positive data on the U.S. label, it's going to take time to negotiate with the Food and Drug Administration.

Second, critics are already poking holes in the study, including the fact that 40% of subjects weren't taking Avandia at the end of the study. It remains to be seen whether that'll create problems for Glaxo's attempts to get the label changed.

But more importantly, there are plenty of other diabetes drugs on the market. If Avandia was the only drug available, doctors would probably shrug off Nissen's findings and start prescribing Avandia again. But with drugs like Merck's (NYSE:MRK) Januvia, Takeda's Actos, and Byetta from Amylin Pharmaceuticals (NASDAQ:AMLN) and Eli Lilly (NYSE: LLY) available, there's not much reason to head back to Avandia in droves. Plus, there's potential for the FDA to approve other diabetes drugs from Novo Nordisk (NYSE:NVO), AstraZeneca (NYSE:AZN), and Bristol-Myers Squibb (NYSE:BMY) in the near future.

Fortunately, Glaxo is large enough to take the hit. Sales of Avandia-containing products were less than 3% of revenue in the first quarter. The new data might be able to stop the bleeding a little, but I feel safe going on the record saying that it's not going to help Avandia make a comeback.

For the record: