UPDATE 4-Schering anesthesia drug effective -US FDA panel

(Updates with safety vote; adds panel, analyst comments, stock action, context)

By Kim Dixon

SILVER SPRING, Md., March 11 (Reuters) - A Schering-Plough Corp (SGP.N) drug aimed at helping patients emerge more quickly from anesthesia appears safe and effective, but it may not always be a better choice than existing therapies, U.S. regulatory advisers said on Tuesday.

A Food and Drug Administration expert panel voted 10-to-0 that the drug is safe and effective. The agency typically follows the advice of its expert panels.

The drug, to be called Bridion and known generically as sugammadex, aims to reverse the effects of certain muscle relaxants and help patients recover more quickly from anesthesia after medical procedures.

"To me it seems yet another alternative," not a major breakthrough, said Julia Pollock, an anesthesiologist, assistant professor at the University of Washington Medical Center and a panel member.

The FDA advisory panel was asked if the drug provided a "clear advantage" over existing therapies.

Instead, most panel members said it was effective and could be a useful addition to their medical toolbox, according to panel chairman John Farrar, an epidemiologist and statistician at the University of Pennsylvania.

Schering-Plough Chief executive Fred Hassan has said the drug could be a growth driver going forward and some analysts have said that, if approved, it could generate between $200 million and $1 billion a year in revenue. Schering-Plough garnered about $13 billion in total revenue in 2007.

Data presented by the company showed it cut the time it took patients to recover from anesthesia by 10 to 20 percent.

Mike Krensavage, an analyst at Raymond James, speculated the drug could cost as much as $100, compared to "just a few dollars" for standard drugs now used to reverse the effects of muscle relaxants.

"If hospitals are willing to pay for it, it will be widely used because of its safety and convenience, perhaps by 25 percent of eligible patients," Krensavage, who attended the meeting, said.

SAFETY ISSUES

Bob Rappaport, director of the FDA's division of anesthesia, analgesia and rheumatology drugs, earlier told the panel that data received in the last two weeks by the FDA raised "concerns" about the drug's safety.

Several FDA staffers said the safety review is ongoing, because the agency needs time to evaluate this new data.

Two potential issues identified by the FDA are the potential for hypersensitivity -- an allergic reaction marked at times by rash and flushing -- and electrical disturbances in the heart.