To: Biomaven who wrote (237 ) 11/11/1997 8:55:00 PM From: Miljenko Zuanic Respond to of 328
News on SELEX: ( BW)(NEXSTAR-PHARMA)(NXTR) NeXstar Pharmaceuticals Announces SELEX Compounds Detect, Fight Inflammatory Disease in Animals Business/Health Editors BOULDER, Colo.--(BW HealthWire)--Nov. 11, 1997--This month, two leading scientific journals have published results of preclinical research conducted by NeXstar Pharmaceuticals, Inc. (NASDAQ: NXTR) and independent researchers using compounds developed through one of NeXstar's proprietary drug discovery technologies called the SELEX process. The journals "Current Biology" and "Chemistry and Biology" have published results from preclinical studies that demonstrate the efficacy and therapeutic potential of SELEX-derived compounds, called aptamers, in detecting and treating inflammatory disease in animals. "This is the first time this novel type of compound was used in vivo (in the body) and proved to have protective effects in the inflammatory lung model," said Dr. Peter Ward, professor and chairman of the Department of Pathology at the University of Michigan School of Medicine. "This verifies this class of compounds can be effective as anti-inflammatory agents and deserves additional study." The paper published in "Current Biology," titled, "Protective Effects of an Aptamer Inhibitor of Neutrophil Elastase in Lung Inflammatory Injury" details how researchers used an elastase inhibitor to reduce damage to the lungs in animals undergoing an inflammatory attack. These studies target animal models for Acute Respiratory Distress Syndrome (ARDS), a disease that threatens the lives of approximately 150 thousand Americans annually, and for which there is no effective treatment. The aptamer blocks the action of elastase, an enzyme which degrades lung connective tissue when released inappropriately by white blood cells. If left untreated, this degradation can lead to lung failure and death. In addition to reducing lung damage, the research shows that the elastase aptamer prevents the white blood cells from further infiltration of the lungs, which may help to break the disease cycle. This work was a collaboration between scientists at NeXstar Pharmaceuticals and at the University of Michigan Medical School. The paper published in "Chemistry & Biology," titled "In Vivo Imaging of Inflammation by an Aptamer Inhibitor of Human Neutrophil Elastase," shows that the same aptamer may be used to detect hidden sites of infection and inflammation in animals. NeXstar scientists modified the elastase aptamer to carry a radioactive compound which would allow it to be visualized by a gamma-ray camera. When injected into a rat, the aptamer was attracted to the white blood cells at the site of inflammation in the body, producing an image of the "hot spot," or inflammatory region. This technology has the potential to provide faster imaging at hidden sites of infection or inflammation. "These results confirm our expectations of the in vivo activity of our aptamers as demonstrated in these animals studies, as well as in other animals studies with our first several aptamers that are currently under development," said Larry M. Gold, Ph.D., chairman and chief scientific officer of NeXstar Pharmaceuticals. "As a result, we continue to see strong evidence to support the power of the SELEX process as a rapid drug discovery engine." Aptamers are compounds that have been identified from libraries of trillions of candidates by the SELEX process. These molecules can bind tightly and specifically to many types of targets, including disease-causing molecules such as elastase. Because the SELEX process is carried out in test tubes, other types of chemicals can be combined into the SELEX libraries to produce completely new classes of a pharmaceutical products. In the case of the elastase inhibitor, the aptamer was blended with a small molecule. This combination is capable of forming a chemical bond that inactivates the elastase. DNA, by itself, is not capable of forming such a bond. However, the combination of the aptamer and small molecule reacts much faster with elastase than the small molecule alone, creating the most potent inhibitor of elastase produced by the pharmaceutical industry to date. NeXstar Pharmaceuticals Inc. is a commercial pharmaceutical company engaged in the discovery, development, manufacturing and marketing of products to treat serious and life-threatening illnesses. The company currently markets two drugs in the United States and around the world, AmBisome and DaunoXome. Based in Boulder, Colo., NeXstar Pharmaceuticals maintains additional research, development and manufacturing facilities in San Dimas, Calif., and marketing subsidiaries worldwide. Note to Media: This release can be obtained from our Internet homepage atnexstar.com . << mz