Washington Editor

MiddleBrook Pharmaceuticals Inc.'s stock skyrocketed Thursday after the FDA approved its once-daily, extended-release amoxicillin tablet, Moxatag.

The Germantown, Md.-based company's shares (NASDAQ:MBRK) soared 139.2 percent, or $1.74, to close at $2.99.

Moxatag 775 mg is indicated as an anti-infective treatment for pharyngitis or tonsillitis secondary to Streptococcus pyogenes, commonly called strep throat. The drug is the first product approved for MiddleBrook, Robert Bannon, the firm's vice president of investor relations, told BioWorld Today.

The company used its proprietary Pulsys once-daily pulsatile delivery technology to develop Moxatag, Bannon explained. Tablets produced using the Pulsys technology are comprised of an immediate-release agent, such as amoxicillin, which is embedded in pellets that have been designed to release the drug at specific points of time in different parts of the gastrointestinal tract, he said.

Moxatag is intended to provide a once-daily alternative to other antibiotics, such as penicillin and amoxicillin, which must be taken several times a day over a treatment course, Bannon said. MiddleBrook also is developing a once-daily formulation of the anti-infective cephalexin, he noted. The company currently markets Keflex, a cephalexin product the firm acquired in June 2004 from Indianapolis-based Eli Lilly and Co., Bannon said.

MiddleBrook ultimately plans to apply its Pulsys technology to the Keflex-branded cephalexin product "much the same way we have now accomplished with amoxicillin," he said.

Results from a Phase III clinical study of more than 600 patients showed that a 10-day course of once-daily Moxatag 775 mg was effective in eradicating bacteria responsible for strep throat and demonstrated statistical noninferiority to a four-times-daily dosage of penicillin for 10 days.

In the double-blind, randomized, parallel-group, 50-center noninferiority trial, MiddleBrook compared a 10-day course of once-daily Moxatag 775 mg tablets with 250-mg penicillin taken four-times daily for 10 days.

Bacteriological eradication at the post-therapy test-of-cure visit in the per-protocol population was 85 percent for the Moxatag group compared with 83.4 percent for the penicillin group.

In compliance with the Pediatric Research Equity Act, MiddleBrook has agreed to continue to study a sprinkle formulation of Moxatag in pediatric patients younger than 12. The firm said it will submit a completed study report and data set for Moxatag in pediatric patients younger than 12 years within the next five years as part of its commitment.

Bannon noted that an earlier Phase III study of the sprinkle formulation failed to achieve its desired microbiological and clinical endpoints.

The trial compared Moxatag 775 mg or 475 mg sprinkle dosed once-daily for seven days with an oral suspension of 10 mg/kg of penicillin dosed four-times daily for 10 days. However, Moxatag failed to demonstrate statistical noninferiority of bacterial eradication at the post-therapy test-of-cure visit for patients who successfully completed the trial protocol, Bannon said.

The company will conduct a Phase II trial first with the sprinkle formulation to determine what dosage strength and course length will work best for pediatric patients before attempting another Phase III trial, he explained.

Bannon noted that amoxicillin is the most prescribed drug by pediatricians among all therapeutic classes.

A once- or twice-daily sprinkle formulation, he added, will make it much easier for the drug to be administered to children.

MiddleBrook hopes to have Moxatag 775 mg tablets on the market by next fall or winter, in time for the 2008-2009 strep throat season, Bannon said.

He noted that the firm had intended to have a broader manufacturing process but ran into trouble with the FDA when it submitted its initial new drug application (NDA) in December 2006.

MiddleBrook resolved the problems, which were brought to the company's attention in a February 2007 "refusal to file" letter from the FDA, by deciding to hold back on its broader manufacturing plans. The company resubmitted its NDA in March, which was accepted by the agency two months later.

MiddleBrook, which changed its name last year from Advancis Pharmaceutical Corp. after being sued by French firm Aventis, now Sanofi-Aventis, which claimed the firm's name was too similar to its own, is considering partnering options for marketing Moxatag, Bannon said.

He noted that the company currently is undergoing a strategic evaluation process, which could lead to the sale of the firm.