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| |  New Oral Drug May Treat Colon Infections TARRYTOWN, N.Y. -- June 23, 1997 -- Researchers announced results of a human study demonstrating that nisin, the company’s proprietary antimicrobial peptide, was successfully delivered orally, in the form of a tablet, to the colon. The study was designed in collaboration with George A. Digenis, PhD, Professor of Medicinal Chemistry and Pharmaceutics, University of Kentucky, Lexington, Kentucky. "The results of this study represent a major milestone in the development of nisin, which may have the potential to be the first peptide that can be taken orally as a treatment for a serious infectious disease of the colon," Dr. Digenis said. 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. Nisin is being developed by AMBI Inc. for the treatment of severe bacterial infections of the colon. Solomon Mowshowitz, PhD, AMBI’s Vice President, Research and Development, presented the images and the data from this and other studies on the role of nisin as a possible oral treatment for diseases of the colon, at the "Gastrointestinal Disorders" conference today in London, England. The compound 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 get their name from the fact that they are resistant to vancomycin, an agent frequently referred to as the "drug of last resort." "Now that we have preclinical efficacy data and a proven means of delivering nisin orally in humans, we will seek a corporate pharmaceutical partner to co-develop and commercialize nisin in the U.S. and Europe, as a potential treatment for serious bacterial infections of the colon," said Fredric D. Price, President and Chief Executive Officer of AMBI. "These infections can be life-threatening, especially to cancer, AIDS, and organ transplant patients." Delivering Nisin orally to the colon Peptides, being small proteins, are normally destroyed by digestive enzymes that are found in the gastrointestinal system. As a result, peptides are usually delivered by injection, where they travel not only to their target site but throughout the body. This can cause unintended side effects. The proprietary delivery system used in this study addresses two concerns: first, nisin can be taken orally and, second, it travels to the site of infection, the colon, and does not end up in other parts of the body. AMBI developed the oral delivery system for nisin in collaboration with Adel Sakr, PhD, professor and director of the Industrial Pharmacy Graduate Program, College of Pharmacy, at the University of Cincinnati. Wolfgang A. Ritschel, MD, PhD, Professor of Pharmacokinetics and Biopharmaceutics and Chairman of the Division of Pharmaceutics and Drug Delivery Systems, also at the University of Cincinnati provided assistance on this project. Preclinical studies have shown that nisin delivered to the colon was found to be intact, indicating that the peptide had maintained its antibacterial activity. Treatment of C. difficile-associated diarrhea and eradication of VRE "C. difficile and VRE are important causes of hospital-acquired morbidity. Any new treatments that are safe, well tolerated and cost-effective would be most welcome. Nisin certainly appears to be an agent worthy of clinical study as a potential weapon against both of these stubborn infections," stated David Sachar, MD, Burrill B. Crohn Professor and Director, Division of Gastroenterology, Mount Sinai School of Medicine, New York. A comparative laboratory study of nisin, vancomycin and metronidazole indicated that nisin was at least seven times more active than the other agents against C. difficile taken from 60 patents, without affecting the predominant "good" bacteria living in the colon that can be killed by other agents. C. difficile infection is believed to be the most common hospital-acquired infection; approximately 7 percent of hospitalized patients in the U.S. manifest clinical symptoms, and it can have significant adverse clinical effects, especially in cancer, AIDS, or intensive care patients. Approximately 200,000 patents develop pseudomembranous colitis, a severe consequence of the infection. In the laboratory, nisin has been shown also to kill VRE that are resistant to all antibiotics in current use. The Centers for Disease Control and Prevention reported in 1994 that Enterococci had become the fourth most frequent infection-causing organisms in hospitals, representing 14 percent of the total. More than 10 percent of Enterococci isolated in hospitals are estimated to be vancomycin-resistant. The presence of VRE in the colon of hospitalized patients represents a threat of severe systemic infection to the patients themselves, as well as to other patients to whom the VRE can spread. About AMBI Inc. AMBI develops and commercializes dietary products for cardiovascular and other conditions and develops pharmaceuticals for serious infectious diseases.
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