Shares of drug maker Cephalon (NASDAQ: Cephalon) jumped in Monday trading as a Wall Street Brokerage Firm raised the rating of the stock on Monday despite a delay in approval for a new drug.

Cephalon jumped $3.93, or 5.5 percent to $75.15 in afternoon trading on the Nasdaq, after Jefferies & Co. brokerage analyst Robert W. Baird increased the rating of the stock to buy.

He said that though the firm's Nuvigil product, which treats excessive sleepiness, is expected is to be approved by the FDA three months later than expected, the delay is non-critical.

Provigil, an established drug from Cephalon which also treats sleepiness, is expected to continue to be one of the company's solid growth drivers over the long term.