New drug to control nerve pain and seizures

After a 6-month delay, Pfizer Inc. is selling a new drug that could help millions of people with chronic nerve pain and seizures and be a billion-dollar blockbuster for the world's largest drug maker.

Developed at Pfizer's Ann Arbor research facilities, Lyrica is approved by federal regulators to treat three specific ailments: the nerve pain associated with diabetic neuropathy, nerve pain that often accompanies shingles, and for partial onset seizures, the most common type of epileptic seizure.

"These three indications will meet the needs of potentially millions of patients," Toni Hoover, who has led the Lyrica development team since 1998, said Monday.

Lyrica won federal approval to treat diabetics and shingles sufferers in early January, and Pfizer said it would be available by the end of March.

But, according to Hoover, release of the drug was delayed when it was classified by the federal Food and Drug Administration as a low-level controlled substance. That triggered a subsequent review, including a comment period, by the Drug Enforcement Agency.

"We thought we would go through that process more quickly," said Hoover, vice president of development for Pfizer Global Research and Development.

In the meantime, Pfizer received approval for the third use of Lyrica, to treat epileptic seizures.
The delay enabled the company to complete the labeling process and train a 2,500-person sales staff to educate doctors, pharmacists and health professionals on all three applications for the drug.

Lyrica's Class 5 classification -- lowest of all for controlled substances -- puts it in the same category as some cough medicines with codeine, for example. Physicians and pharmacists will follow slightly different procedures in prescribing and tracking the medication, but "patients should not experience any difference," Hoover said.

Nearly half of the 18 million American with diabetes will develop some form of diabetic neuropathy and about 3 million will experience painful neuropathy in their feet, legs, hands or arms. An estimated 50,000 Americans develop nerve pain from shingles, a skin disease caused by reaction to the same virus that causes chicken pox.

The market for nerve pain treatment alone could generate $1 billion in sales, estimated Trevor Polischuk, a pharmaceutical analyst with money manager OrbiMed Advisors in New York. He estimates the market for treating epileptic seizures could be a $500-million market.

Lyrica is the next generation drug in a class developed and controlled exclusively by Pfizer -- alpha-2 delta ligands. Lyrica works like a blanket, dampening hyper-excitable nerve endings that cause not only pain and seizures, but also psychiatric disorders such as anxiety.

One application -- to treat general anxiety disorder -- initially was rejected by the FDA. Pfizer continues to work with regulators, but has not resubmitted an application.

However, Pfizer has filed an application in Europe seeking approval for the use of Lyrica to treat general anxiety disorder. The approval process is expected to take about a year.

The use of Lyrica to treat anxiety disorder could present the most lucrative market because of the potentially huge demand. Polischuk estimated it could be upward of $2-billion, raising it to mega-blockbuster status.

Developed from a chemical acquired from Northwestern University in 1992, Lyrica has been created almost entirely in Ann Arbor -- first in the research and development labs of Parke-Davis, then Warner-Lambert, then Pfizer, as each was swallowed by its successor.

Given the potential uses for alpha 2 delta ligands, the Ann Arbor research facility, which employs 2,500 people, is poised to play a key role in the development of future Pfizer products.