Major review of 166 studies says best diabetes drug is cheapest

Mar 14, 2011 5:01 PM

A comprehensive review published online today in the Annals of Internal Medicine concludes that the best diabetes drug is one of the oldest and cheapest diabetes drugs: metformin.

That medication costs about 35 cents a pill when bought as a generic, compared with $6.42 a pill for Januvia (sitagliptin), one of the newest diabetes on the market. Moreover, metformin lowers blood sugar at least as well as all other drugs and better than some others, notably Actos (pioglitiazone) and Avandia (rosiglitazone). It also lowers LDL (bad) cholesterol more effectively than most other diabetes drugs. To top it all off, the drug is less likely to cause some of the serious side effects that plague diabetes medications, including dangerously low blood-sugar levels, fractures, heart failure, and weight gain. When metformin plus another drug is needed to control blood sugar levels, the report says that all options are about as effective, so the choice should depend mainly on the risk of side effects.

Metformin, alone or combined with other medication, has been our Best Buy Drugs pick for type 2 diabetes since we started the program, in 2004.

The review, which was conducted by the Johns Hopkins University Evidence-based Practice Center and funded by the federal Agency for Healthcare Research and Quality, looked at 140 randomized clinical trials and 26 observational studies published through December 2010. To evaluate as much evidence as possible, the researchers did a comprehensive online search, hand searched 15 leading journals, asked expert reviewers to provide additional citations, and contacted the U.S. Food and Drug Administration, as well as Canadian and European health agencies and several pharmaceutical companies. Investigators then reviewed each study and graded them based on the quantity, quality, and consistency of results.

"Such systematic reviews that compare one drug or drug combination against another, are exactly the kind of research we are going to see more of--and need more of--now that health reform is the law of the land," says Marvin M. Lipman, M.D., a diabetes specialist and the chief medical adviser to Consumer Reports. "They provide the clearest guidance to doctors and patients of what really works, and what doesn't."

In this case, says Lipman, "the results show once again that the best medical choices are often the least expensive ones."

--Joel Keehn, senior editor

See our tips for managing diabetes, our Best Buy Drugs report on diabetes, and our Ratings of home glucose monitors.