AMBI Receives FDA Clearance To Initiate Clinical Trial For Nisin As A Potential Treatment For Infections Of The Colon.

TARRYTOWN, N.Y.--(BUSINESS WIRE)--November 18, 1997--AMBI Inc. (Nasdaq: AMBI) was informed by the US FDA that it could initiate a clinical trial under an Investigational New Drug (IND) application for the use of orally administered nisin as a potential treatment for severe bacterial infections of the colon.

Nisin has been shown in preclinical studies to kill both Clostridium difficile (C. difficile), an organism responsible for antibiotic-associated diarrhea; and vancomycin-resistant-enterococci (VRE), bacteria that put patients at risk for lethal systemic infections. Nisin has been found to be significantly better than vancomycin and metronidazole in an in vitro laboratory study of 60 clinical isolates of C. difficile, and was also effective against 90 clinical isolates of VRE, for which vancomycin, the "drug of last resort", is not effective. In vitro studies also demonstrated that normal "good" colon bacteria are not affected by nisin.

Solomon Mowshowitz, PhD, AMBI's Vice President, Research and Development said, "The FDA clearance to begin testing of nisin in humans represents an important achievement for the Company. It is our second drug candidate to be tested in humans; it follows the study in Europe of the use of nisin in humans as a potential treatment for ulcers caused by the bacterium Helicobacter pylori. We are seeking development partners for these and our other antibacterial drug candidates."

Oral protein delivery is key to potential treatment for severe colon infection

AMBI developed a tablet that enables nisin to be taken orally. Normally, proteins such as nisin are destroyed by digestive enzymes that are found in the small intestine, but the Company's proprietary tablet delivery system, which has been studied in healthy human volunteers, has demonstrated that nisin can be taken orally and delivered to the colon, the site of severe infections.

The delivery study was designed in collaboration with George A. Digenis, PhD, Professor of Medicinal Chemistry and Pharmaceutics, University of Kentucky, Lexington, Kentucky. The study used radiolabeling technology in which images of the tablets were captured as they traveled intact through the stomach and the small intestine and then released nisin at the ileocaecal junction, where the small intestine meets the colon.

C. difficile and VRE are both serious hospital-acquired infections with high associated morbidity. C. difficile affects approximately 7% of hospitalized patients and is believed to be the most common hospital-acquired infection. Approximately 200,000 patients develop pseudomembraneous colitis, a severe form of the infection. Enterococci reside in the colon of most people and VRE is found in about 1% of the population. Enterococci represent the fourth most common hospital-acquired infection, accounting for 14% of the total. Systemic infections can arise in immunocompromised patients, such as those with cancer, AIDS, and others in intensive care, when VRE makes its way from the colon into the blood.

The IND application was reviewed by the FDA's Division of Special Pathogens and Immunologic Drug Products at the Center for Drug Evaluation and Research (CDER), a newly established division set up to deal with the treatment of serious infectious diseases, including antibiotic-resistant bacterial infections such as VRE and the emerging vancomycin intermediately resistant Staphylococcus aureus (VISA).

AMBI develops and commercializes nutrition products for cardiovascular and other conditions and develops pharmaceuticals for serious infectious diseases.

The statements in this press release that are not historical facts are forward-looking statements based upon current expectations. Such forward-looking statements involve risks and uncertainties, including risks and uncertainties set forth in "Risk Factors" and elsewhere in AMBI's Registration Statement on Form S-3 and the Prospectus dated June 27, 1997 and AMBI's Form 10-K for the year ended June 30, 1997. Actual results and timing of certain events could differ materially from those indicated in the forward-looking statements as a result of these and other factors

CONTACT: AMBI Investor Relations

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