(August 7, 2006) -- The research chief of Cephalon Inc said on Tuesday he is "cautiously optimistic" the U.S. Food and Drug Administration will approve the company's experimental drug for attention deficit disorder, based on new safety data provided by the drugmaker.

"We believe we've provided the agency with the evidence that they'll be comfortable with," Jeffry Vaught said in an interview. He said the FDA could decide the fate of its Sparlon drug -- which contains the same active ingredient as Cephalon's Provigil medicine to treat sleep disorders -- sometime next month.

Cephalon suffered a major setback in March when an FDA advisory panel said Sparlon was not safe enough to win approval for attention deficit disorder even though data showed it was effective.

Vaught said the panel voted 12-1 against the drug's safety based on concerns that a patient in clinical trials may have developed a dangerous skin rash called Stevens Johnson Syndrome. But the company has since provided the FDA data it believes clearly show the child had a far less-dangerous type of rash.

Vaught said the FDA's advisory panel would not have had safety concerns if it had the new data recently provided the FDA by Cephalon. "There's no question about it -- it would have been a totally different meeting."