FDA panel backs inhaled insulin

WASHINGTON, Sep 08, 2005 (United Press International via COMTEX) -- A government advisory panel backed approval of an insulin inhaler Thursday, for the first time potentially offering adult diabetics an alternative to injections for controlling their blood sugar.

Experts recommended Food and Drug Administration approval of the drug by a 7 to 2 vote, despite what many said were serious concerns about its long-term safety and ease of use by patients.

If approved, the drug, known as Exubera, would represent the first major shift away from needles and syringes for millions of diabetics who must take daily injections to control glucose. The product works much like inhalers already used by asthma and allergy sufferers, by producing an insulin-powder cloud inhaled via a handheld plastic machine.

Pharma companies have long sought to offer diabetics a way to take what for many patients amounts to multiple daily insulin doses without painful needle sticks. The drug has been in development for a decade and is now backed by a joint venture between Pfizer, Sanofi-Aventis and Nektar Therapeutics.

An estimated 18 million Americans -- more than 6 percent of the population -- have diabetes. Most suffer from Type 2, in which the body fails to react to the insulin it produces naturally. About 1.5 million patients with Type 1 must inject insulin before every meal, because their immune systems have damaged or destroyed their ability to manufacture it.

Up to two-thirds of all diabetics do not adequately control their blood sugar, according to the American Academy of Clinical Endocrinologists. Poor control over the long term can lead to blood-vessel and organ damage, blindness, kidney failure and foot ailments.

Diabetes was the nation's sixth-leading cause of death in 2003, totaling $132 billion in medical expenses and lost productivity, according to the American Diabetes Association.

Pfizer presented several studies showing Exubera controlled blood sugar as well as insulin shots for up to two years in patients with both forms of diabetes.

FDA officials said they were concerned less than 30 percent of Type 1 patients using the drug lowered their blood sugar to recommended levels after six months of use.

"Questions remain about whether adult Type 1 diabetics can expect to achieve tight glycemic control with Exubera," said Dr. Karen M. Mahoney, an FDA safety official.

While Exubera could result in far fewer injections for some patients, many still will have to use needles, even if regulators approve it. The drug does not replace longer-acting insulin, which many diabetics now inject. In addition, patients who smoke will be excluded from taking the drug, because of evidence that damage from cigarettes boosts patients' exposure to insulin.

"To have people rush to the this product saying, 'I can throw away my syringes' ... is simply an incorrect message and that needs to be emphasized more," said Dr. Paul D. Woolf, chief of medicine at Crozer Chester Medical Center in Upland, Pa., and acting chair of the advisory panel.

At the same time, several experts said they worried the drug's sponsors had not done enough to prove it is safe in diabetics exposed to secondhand smoke or those with lung diseases such as asthma or emphysema. That was a particular concern in light of evidence the drug led to minor but consistent reductions in breathing efficiency in most patients who used it for more than a few months.

The company committed to a 12-year study of Exubera's effects in patients with lung disease as soon as the drug hits the market.

"We understand the need to continue to assess the long term effects on pulmonary function," said Dr. Neville Jackson, a Pfizer official.

The FDA also should require the companies to come up with a detailed training program instructing doctors and patients on using the inhaler, several advisers said. Many pointed to decades of experience with asthma inhalers, which often frustrate physicians, because improper or spotty use by patients compromises their effectiveness.

"I think the use of insulin without a needle, the siren call of that is almost irresistible," said Rebecca W. Killion, the panel's patient representative -- herself a diabetic. "The practicality issue, though ... is huge."

Jackson said patients and doctors would get "intensive training" on using the inhaler properly.

The companies did not seek approval for adolescents and children -- two groups that could benefit greatly from a needle-free product. Earlier studies were stopped because of uncertainly about the drug's effect on breathing.

"We intend to restart pediatric studies after consultation with the agency," Jackson said.

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Todd Zwillich covers healthcare matters for UPI. E-mail: sciencemail@upi.com