By Mary Welch

Taking aim at antibiotic-resistant bugs by going after proteins on their surfaces, four-year-old Inhibitex Inc. uses antibodies that bind to Microbial Surface Components Recognizing Adhesive Matrix Molecules (MSCRAMMs) to prevent hospital-acquired infections and to create specific antibodies against such microorganisms as Staphylococcus aureus in plasma donors.

"It's well accepted that prevention of microbial adherence will dramatically reduce the progression of infection," said William Johnston, president and CEO of Norcross, Ga.-based Inhibitex.

MSCRAMMs occur on all bacterial microorganisms.

"These proteins allow the bacteria to bind to host tissues or implanted biomaterials, thus initiating the infection process," said Johnston, president and CEO.

The company's antibody-based hyperimmune intravenous gamma globulins, based on selecting or stimulating hyperimmune plasma, form the foundation for its products targeted to humans, designed to prevent or attack the staph bug. A program in donor stimulation involves vaccinating plasma donors with Inhibitex's recombinant MSCRAMM protein, which produces specific antibodies against S. aureus in their plasma. The antibodies produced in vaccinated donors will be isolated from their plasma, and are expected to form the basis of a second-generation product to prevent and treat hospital acquired infections.

Inhibitex also has a vaccine under development that targets bovine mastitis, a disease that affects the dairy industry.

The company has nine issued patents (and 11 patent applications pending) on several of the MSCRAMM genes and proteins.

"Thirty percent of hospital-acquired microbial infections are resistant to antibiotics," Johnston said. "We're especially targeting S. aureus and coagulase negative staphylococci," Johnston said. "These organisms, which are often resistant to antibiotics, represent the most significant cause of nosocomial [hospital-acquired] infections. In fact, the total U.S. market for prophylactic treatments for these infections is more than $250 million. What we want to do is produce prophylactic and therapeutic responses — stop the infection before it begins or halt its ability to progress, which could mean that it would be used in conjunction with antibodies."

Inhibitex's lead product is an antibody preparation for the prevention and treatment of S. aureus infections in a hospital setting, and is aimed at high-risk patients: diabetics, intravenous drug users, patients undergoing hemodialysis, low birth weight neonates, surgical patients and people with AIDS.

Johnston said the company will decide within six months whether or not to enter clinical trials with its lead product.

Inhibitex was founded in 1994 by two researchers from Texas A&M University, in Houston, who had contributed to the discovery of components of the technology and saw antibiotic-resistant bacteria developing rapidly. They used seed funding from the AM Fund, of Bryan, Texas, to secure the Texas A&M technology as well as other critical patents.

The company moved to Atlanta this year. "For a company fighting infectious diseases, it's an advantage to be in the same city with the [Centers for Disease Control]," Johnson said.

Two financing rounds led by Alliance Technology Ventures and Cordova Technology Partners, both of Atlanta, raised $3 million of the company's $3.7 million raised so far. Inhibitex, now with nine employees, intends to staff up to about 15 in the near future. Early next year, the company is moving and will occupy about one-fifth of an $8.5 million, 50,000-square-foot facility in Alpharetta, Ga., north of Atlanta. Inhibitex recently convened the first meeting of its scientific board. *