West Coast Editor

Building on work with a compound that GlaxoSmithKline plc started developing almost three years ago in a deal with Biosynexus, MedImmune Inc. entered licensing deal with GSK for a number of anti-staphylococcal monoclonal antibodies.

MedImmune's stock (NASDAQ:MEDI) closed Monday at $27.33, up 54 cents.

The deal includes BSYX-A110, which is in Phase II trials for prevention of serious bloodstream infections caused by Staphylococcus in low-birth-weight infants.

"There's analysis going on now of the Phase IIa data, and a safety and efficacy Phase IIb trial is scheduled for 2006," said Jamie Lacey, director of public relations for Gaithersburg, Md.-based MedImmune.

Under the terms, MedImmune will handle future research and development of BSYX-A110 and any resulting second-generation MAbs as well as all future sales and marketing activities worldwide.

London-based GSK is providing an up-front payment upon signing, as well as milestone payments and royalties on future marketed products. MedImmune also has assumed responsibility for future milestone and royalty payment obligations to Biosynexus, of Rockville, Md., from which GSK originally licensed BSYX-A110 and related rights. (See BioWorld Today, Oct. 3, 2002.)

"We're not providing any additional financial terms," Lacey told BioWorld Today.

The Biosynexus deal allowed GSK to develop staphylococcal vaccines using the former's antigen discovery and conjugation technologies, with the companies sharing development costs and Biosynexus gaining as much as $120 million through access fees, equity investments and milestone payments. Lacey said MedImmune would not provide details of how much of the money had been paid to Biosynexus so far.

About 43,000 infants weighing less than 1,250 grams at birth were born in 2001, according to the U.S. Census Bureau. Such babies are particularly susceptible to hospital-acquired infections, such as those caused by Staphylococcus. Among infants in the neonatal intensive care unit, hospital-acquired infection rates range from 6 percent to 25 percent. MedImmune said that reports in medical literature suggest that coagulase-negative Staphylococcus - which the MedImmune/GSK drug protects against - increases an infant's hospital stay by 20 days to 40 days at an added cost of $60,000 to $200,000.

Others are working in the same area. Nabi Biopharmaceuticals Inc., of Boca Raton, Fla., has Altastaph (S. aureus immune globulin) in Phase II for the prevention and treatment of S. aureus infections.

The product contains high levels of antibodies to capsular polysaccharides (the protective outer sugar coatings on S. aureus bacteria) from S. aureus types 5 and 8, which together account for about 85 percent of all S. aureus infections.

At the start of last year, the FDA granted orphan drug status to Altastaph for immediate protection against S. aureus infections in low-birth-weight neonates, and in February 2004 designated the compound as fast track.

Henrik Rasmussen, senior vice president of clinical, medical and regulatory affairs, said he was "not that familiar with the MedImmune compound," but said Nabi will start a Phase II trial next year with an improved version of its own drug, which will protect babies against S. epidermidis, as well as S. aureus.

"Coagulase negative [targeted by BSYX-A110] covers a wide range of staph," he said, noting that the very prevalent coagulase-negative bugs and S. epidermidis germs are "almost synonymous, though not completely."

In May, Nabi began the first human study of its vaccine to prevent S. epidermidis in at-risk patients, which include neonates, patients with in-dwelling catheters and patients undergoing certain types of surgery. The Phase I trial will evaluate the safety and immune response of the vaccine in up to 48 patients at four dosage levels, with results expected in the second half of the year.

Meanwhile, another firm is even farther along with a staph drug. Alpharetta, Ga.-based Inhibitex Inc. has Veronate in Phase III trials, begun in May against S. aureus. A little more than a week ago, the company entered agreements to raise $41.3 million for its efforts through a private placement. (See BioWorld Today, Aug. 19, 2005.)

"They are ahead of the pack," Rasmussen said of Inhibitex, though Veronate lacks activity against S. epidermidis.