Nov 6 (Reuters) - Novo Nordisk's new ultra long-acting insulin degludec is associated with a higher heart risk than other diabetes treatments, although the size of the risk is uncertain, U.S. regulators said on Tuesday.
Staff from the U.S. Food and Drug Administration (FDA) said they would be asking an expert panel later this week whether the Danish drugmaker should carry out more safety studies before the new insulin is approved.
Initial assessments based on a pooled analysis of 16 clinical studies suggested degludec could increase the risk of cardiovascular death, non-fatal heart attack, non-fatal stroke and unstable angina by 10 percent relative to comparators.
But a later updated analysis put the increased risk at 30 percent. In both cases, however, the statistical uncertainty was large.
Staff from the U.S. Food and Drug Administration (FDA) released their review ahead of an advisory committee of outside experts, which will vote on Nov. 8 on whether to recommend the drug.
The FDA will make a final decision later, taking into account the advisers' recommendations.
Novo is the world's largest insulin maker and any setback for degludec, which the Danish company plans to market under the brand name Tresiba, would be good news for rivals Sanofi and Eli Lilly.
Degludec is associated with a lower risk of hypoglycemia, or dangerously low blood sugar, but this benefit has to be weighed against potential risks, notably its effect on heart function, which is a particular concern with new diabetes drugs.
Shares in Novo were 1.3 percent lower by 1315 GMT after the release of the FDA documents on the regulator's website.
Degludec was recommended for approval by the European Medicines Agency last month, but the U.S. decision is seen as pivotal, since this is where the bulk of future sales are expected to be.
Worldwide sales of degludec are expected to reach $1.5 billion by 2016, according to consensus forecasts compiled by Thomson Reuters.
Novo's chief scientific officer said last month he was confident about the safety of degludec and optimistic about U.S. approval.