BEIJING, Jan. 3 -- Pfizer Inc, the world's largest drugmaker, said it won US approval to sell its Lyrica pill to treat nerve pain associated with diabetes and shingles.

    The Food and Drug Administration (FDA) continues to review Lyrica as a seizure treatment for adults, Pfizer said in a statement on Friday. The company said it expects the Drug Enforcement Administration to classify Lyrica as a controlled substance under rules intended to limit prescription drug abuse.

    Chief Executive Officer Hank McKinnell, battling a sliding stock price and fallout from a study linking Pfizer's Celebrex painkiller to heart attacks, is counting on new drugs such as Lyrica to heighten sales as some of the company's biggest products face competition. Lyrica is the successor to Pfizer's epilepsy drug Neurontin, which had US$2.2 billion in US sales in 2003 before generic competitors entered the market this year.

    "Having the product available for most of 2005 is a big positive for the company," said Trevor Polischuk, a pharmaceuticals analyst at New York-based Orbimed Advisors, which manages investments including Pfizer shares. Pain is the most important indication for Lyrica, Polischuk said.

    The FDA in September rejected Lyrica as a treatment for an anxiety disorder and requested more information from New York-based Pfizer before approving the drug for nerve pain and epilepsy. Pfizer and regulators declined at the time to say what new data the FDA wanted.

    Pfizer shares slipped 12 cents to US$26.89 at 4 pm on Thursday in New York Stock Exchange composite trading. They had fallen 24 per cent this year, making Pfizer the fourth-worst performer in the Dow Jones Industrial Average.

    Pfizer will have to persuade doctors and consumers to try Lyrica instead of generic copies of Neurontin, which doesn't have the same Drug Enforcement Administration restrictions. That drug's label tells doctors "the abuse and dependence potential of Neurontin has not been evaluated in human studies."

    The Drug Enforcement Administration likely will place Lyrica in a category that indicates its potential for abuse is less than that of other so-called scheduled drugs, Pfizer said in its statement. Pfizer couldn't immediately release Lyrica's prescribing label, which will dictate how the company can market the drug, company spokeswoman Mariann Caprino said in an e-mailed statement on Friday.

    Lyrica's "label now goes to the drug enforcement agency, which will make the scheduling classification," Caprino wrote.

    Under federal law, the FDA and DEA work together to prevent abuse of prescription drugs.

    Worldwide sales of Lyrica as a treatment for pain and seizures may reach US$2.9 billion by 2008, said Sena Lund, an analyst with Cathay Financial in New York, who has a "neutral" rating on Pfizer and owns the stock. He didn't immediately have a sales estimate for Lyrica as a pain treatment only, although he said more than 70 per cent of Neurontin's sales come from uses other than epilepsy.

    "The important thing is they got approval," Lund said.

    Diabetes can damage nerves over time, leading to numbness or pain in hands, arms, feet and legs, according to the National Institutes of Health. Almost half of the 18 million Americans with diabetes will develop some form of nerve pain, Pfizer said in a statement on Friday.

    Pfizer hasn't set a date for Lyrica's introduction in the US or a price for the drug, Caprino said. The Internet pharmacy, http://www.drugstore.com sells 270 capsules of generic gabapentin, the key ingredient in Neurontin, for US$209.98.

    Lyrica will compete with Eli Lilly & Co's Cymbalta antidepressant, which was cleared by the FDA in September as a treatment for peripheral neuropathic pain. Cymbalta was the first drug in the United States specifically approved for that use. Pfizer won European approval in July to sell Lyrica for epilepsy and nerve pain.

    Doctors have treated diabetes-related nerve pain with antidepressants and epilepsy drugs such as Neurontin, even without FDA approval. While doctors are free to prescribe drugs for off-label uses, drugmakers aren't allowed to promote their medicines for those conditions. Pfizer gained Neurontin when it purchased Warner-Lambert in 2000.

    In May, Pfizer agreed to pay more than US$430 million to settle charges that a Warner-Lambert unit promoted Neurontin, approved by the FDA only as a supplemental drug to help combat epileptic seizures, as a treatment for Lou Gehrig's Disease, attention deficit disorder and drug and alcohol seizures.

    Pfizer twice delayed asking regulators to approve Lyrica. In December 2001, Pfizer postponed filing an application for Lyrica, at the time known as pregabalin, when the FDA stopped the company from continuing trials after a study linked the drug to an increased incidence of tumours in mice.

    Six Pfizer drugs are set to face generic competition in the next six years, including the antidepressant Zoloft in 2006 and the blood-pressure treatment Norvasc in 2007.

    Pressure for lower drug prices, patent expirations and competition to some of Pfizer's top products will temper revenue and income growth in 2005, the company said in October.

    
(Source: China Daily/Kerry Dooley and Nicole Ostrow)