With an FDA advisory committee meeting looming next month, Bristol-Myers Squibb and AstraZeneca posted new two-year data on their diabetes drug dapagliflozin, underscoring its potential as a whole new way to lower blood sugar in patients. But several of the reports covering the data quickly highlighted 18 cases of cancer found among patients taking the drug.
Dapagliflozin is an SGLT-2 inhibitor, which is designed to spur the body to purge excess blood sugar in urine. A number of companies, including Eli Lilly, J&J and Boehringer are all pursuing a similar pathway. But among the more than 5,000 patients who took the new drug from BMS/AstraZeneca, 18 developed breast and bladder cancer compared to only two cases in the control arm. And with malignancy and heart risks linked to currently used standards, the new safety data helped to raise the alarm about the cancer numbers.
Statistically, however, the overall number of cancers was so low that the drug arm and control arm reflected little comparable risk associated with the therapeutic. And that left analysts ready to shrug off the cancer as more anecdotal, unlikely to sway the vote but possibly increasing the chances of a post-marketing safety study requirement for the manufacturers.
"No doubt they'll bring this up at the advisory committee," ISI's Mark Schoenebaum told Bloomberg. "But I'd be very surprised if this blocked approval." Researchers also noted that there were no signs of added cancer risk in preclinical animal studies designed to focus on that issue quite closely. Thomson Pharma has estimated potential 2015 sales of $631 million.
This morning BMS also posted new Phase III data showing that dapagliflozin plus metformin XR significantly reduced blood sugar levels compared to dapagliflozin or metformin XR alone plus placebo.
"As we advance our knowledge of how SGLT2 inhibitors may work as a potential treatment for patients with type 2 diabetes, long-term data become critical to assess a compound's safety and its ability to sustain glycemic control," said Michael A. Nauck, MD, the principal investigator of the study. "These two-year data demonstrated that patients taking dapagliflozin added to metformin sustained reductions in blood sugar levels over an extended period of time."