WASHINGTON Pfizer Inc's experimental rheumatoid arthritis drug goes before an advisory panel next week, a potential blockbuster medicine that would revive faith in the company's research if its benefits are deemed to outweigh its side effects.
Most industry analysts expect the Food and Drug Administration's expert committee to recommend approval despite risks posed by higher-than-normal cholesterol and liver enzyme levels and infections for patients taking tofacitinib during clinical trials.
The pill is one of Pfizer's biggest pipeline hopes and could become one of the few major new medicines to come from its own laboratories since impotence treatment Viagra more than a decade ago. If approved, the likely cheaper pill would compete with widely used injectable medicines, including Abbott Laboratories Inc's $8 billion-a-year Humira.
"We expect a noisy meeting for tofacitinib but ultimately believe the drug will receive a positive vote from the panel and will be approved by the FDA in August," Chris Schott, analyst at J.P. Morgan, said in a research note.
The advisory panel is set to review the drug on Wednesday, after FDA staff release their initial findings on Monday.
Mark Schoenebaum, analyst at ISI Group, said he is predicting approval, but there is always the chance unexpected safety issues dominate discussions next week. "Remember, as with any drug application, the FDA always sees more data than investors get a chance to see," he said.
Morningstar analyst Damien Conover sees the drug having a 65 percent change of getting FDA approval, while other analysts peg the likelihood at 80 to 85 percent.
"The efficacy looks particularly strong. What I think folks are going to discuss is the side effect profile," Conover said.
The FDA usually follows the advice of its advisory panels, although it is not required to.
Pfizer is banking on the drug, the first in a new class of arthritis medications, to replace lost revenue from cholesterol fighter Lipitor, which at its height churned out $13 billion in annual sales. Lipitor began facing cheaper generics in the United States last November.
Pfizer's treatment has also weighed on Abbott, whose investors fear tofacitinib could slow down Humira's sales. But many industry analysts, and Abbott itself, project continuing double-digit annual growth for Humira, helped by a long record of safety and effectiveness.
Rheumatoid arthritis, a potentially crippling condition in which the body's own immune system attacks the joints, and related diseases, have been one of the most lucrative areas for drugmakers, with more than $20 billion in annual sales.
An estimated 1.3 million Americans suffer from rheumatoid arthritis, according to the Arthritis Foundation. About 1 percent of the worldwide adult population has the disease.
Most analysts expect peak sales for tofacitinib of $2 billion to $3 billion a year, but say it will take time to get there as doctors grow more comfortable with the drug's safety. Morningstar's Conover expects sales of under $200 million in the first year after approval.
Higher cholesterol and liver enzymes could be a sign of more serious health problems down the line, like heart issues and kidney failure - or innocuous side effects easily fixed with another medication.
As a result, industry analysts see the FDA approving tofacitinib as a third line treatment, when patients have already tried drugs like Humira.
"When we already have good treatments available, and there's no evidence that this drug really is better than others, I tend to encourage patients to go with what I know, which is things like Humira or (Amgen's) Enbrel," said Dr. Scott Zashin, clinical professor of medicine at the University of Texas-Southwestern Medical School.
Humira has been available since 2002. Enbrel, made by Amgen Inc and also injected, has been sold since 1998. Both costly drugs block a protein called tumor necrosis factor (TNF) that is tied to inflammation.
Other big drugs in the increasingly crowded anti-TNF category include Johnson & Johnson's Remicade ($4.6 billion of sales in 2010) and Enbrel ($3.53 billion in 2010).
DOSING, PRICE ATTRACTION
Pfizer's tofacitinib is a traditional chemical pill that works by blocking signals from entering cells that would activate immune and inflammatory responses.
It is the furthest along in its clinical development, ahead of about 11 other drugs in a new category known as JAK inhibitors.
Tofacitinib's most attractive feature over older drugs may be its dosing. Patients take it twice a day in tablet form, rather than having to inject themselves every other week, as with Abbott's Humira.
"The fact that it's oral is a huge advantage," said Dr. Cynthia Aranow, a specialist in rheumatology at the Feinstein Institute for Medical Research in Manhasset, New York.
Doctors say tofacitinib should be less expensive than more difficult to produce biotech drugs, which carry a $20,000 per year price tag, and that a significantly lower price could tip the balance in its favor.
Pfizer declined to speak about pricing issues during an earnings call this week.
Even if doctors do not turn to the drug first, it could help the nearly 30 to 40 percent of patients who fail to benefit from standard injectable treatments, physicians and analysts said.
Pfizer hopes to eventually gain approval for tofacitinib as a first option for patients, or a second option behind decades-old drug methotrexate. It is also studying the drug in conditions like inflammatory bowel diseases, psoriasis and dry eye.
(Additional reporting by Ransdell Pierson; Editing by Michele Gershberg and Tim Dobbyn)