said Friday that the Food and Drug Administration will need an extra three months to review its application for the inhaled insulin Exubera.
No explanation was given by Pfizer or its marketing partner
The agency needs more time to review "additional technical chemistry data" from the companies. Pfizer and Sanofi-Aventis said they will "continue to work closely with the FDA so that this important medicine can be made available for patients."
Exubera is one of several inhaled insulin products in development, and it's far ahead of competitors in the regulatory review process. The FDA had been expected to act today.
Shares of both companies weren't affected. Pfizer's stock was up 16 cents to $21.26, while Sanofi-Aventis' stock was up 1 cent to $39.54.
However, shares of
, the company that developed the inhalation technology, dropped 45 cents, or 3.1%, to $14.31 in heavy trading. The stock dipped as low as $13.63.
"This appears to be a minor delay, with approval likely delayed to the end of January 2006," according to a research note from Sagient Research Systems of San Diego, whose BioMedTracker report analyzes biotechnology issues. "We continue to believe that the FDA will accept the advisory committee recommendations to approve Exubera for patients without underlying lung abnormalities."
Last month, an FDA advisory committee
recommended approval of Exubera for treating adults with type 1 and type 2 diabetes. Type 1 diabetes is caused by the body's inability to produce insulin, the protein hormone that helps turn sugar into fuel for the body's cells. Type 2 diabetes, which is much more common, is caused by cells ignoring insulin or the body's failure to produce enough insulin.
The advisory panel vote was 7-2. Although the FDA isn't bound by panels' recommendations, it usually follows their advice.
Exubera is being presented as equally effective as injectable insulin, but more convenient. "By allowing insulin to be inhaled, Exubera could help dramatically reduce the insulin-initiation hurdles that result from fear of injections and therefore keep millions of patients from attaining appropriate control of their glucose levels," Pfizer says.
The company says up to half of patients with type 2 diabetes who require insulin treatment decline it. Research shows that patients are three times more likely to follow a course of insulin treatment when an inhaled option is available, Pfizer says. But when the cost of inhaled insulin is added to the equation, skeptics say the convenience issue may be overstated.
Another concern is how Exubera and other inhaled insulin products will affect the lungs. The American Diabetes Association notes that "you have to inhale a lot of insulin to get the amount your body needs. That's because only a small percentage of the inhaled insulin actually reaches the bloodstream and lowers blood glucose."
The association adds that although short-term studies say inhaled insulin is safe, "the long-term safety remains a question." The advisory committee said people with lung disease shouldn't use Exubera. Pfizer says it will conduct a long-term study to assess Exubera's effect on lung function.