* Ligand Pharmaceuticals Inc. of San Diego, said that Targretin, thecompany's lead retinoid-based therapeutic compound, hasdemonstrated efficacy as a chemopreventive agent in a well studied,pre-clinical animal model of breast cancer _ the NMU-induced ratmammary carcinoma model. Targretin-treated animals in the studyshowed a 90 percent reduction in tumor burden and tumor incidencecompared to controls. The study results also indicated that Targretinmay offer significant reductions in side effects over other breastcancer chemotherapy agents.

* NeXstar Pharmaceuticals Inc., of Boulder, Colo., said that researchpublished in the Journal of Clinical Investigation provides the firstdemonstration of in vivo efficacy of an aptamer directed against acell surface receptor. In the paper, scientists from NeXstar and theircollaborators describe a series of aptamers, generated by thecompany's proprietary SELEX combinatorial chemistry process thatbind specifically and tightly to L-selectin, a cell surface receptorfound on the surface of most leukocytes.

* Quintiles Transnational Corp., of Research Triangle Park, N.C., hasbeen added to NASDAQ-100 Index of the largest and most activenon-financial issues listed on the NASDAQ Stock Market. Quintiles'total market value of approximately $2 billion is four times greaterthan the $500 million minimum for listing on the index.

* Shaman Pharmaceuticals Inc., of South San Francisco, said thatOno Pharmaceutical Co., Ltd., of Japan, has paid Shaman, $1million for enhanced rights to develop and commercialize Shaman'sdiabetes compounds.

(c) 1997 American Health Consultants. All rights reserved.