The FDA can't confirm any cancer risk associated with Sanofi-Aventis' diabetes drug Lantus. That's the good news. The bad news is that it can't fully clear the cancer-risk cloud, either. The agency has been reviewing the blockbuster treatment since 2009, but after sifting five studies, pronounces the data inconclusive.
The problem is that the studies' various methodologies aren't adequate to address the cancer question. Its review of four published studies determined that evidence of cancer risk was "inconclusive due to methodological limitations." Analysis of a fifth trial didn't turn up evidence of any cancer-risk increase, but the agency said that study also had limitations, Reuters reports. "Our review is ongoing," the FDA said in a statement.
Back when the cancer-risk evidence first surfaced, Sanofi understandably rushed to defend the drug, which is expected to surpass $6 billion in sales by 2014, according to Reuters. The company amended an ongoing trial, Origin, to gauge cancer risk; preliminary data showed no increase in risk. Final results are due late this year. Three additional cancer-specific epidemiological studies are expected by the end of June, the FDA said.