IRVINE, Calif.--(BUSINESS WIRE)--Spectrum Pharmaceuticals, Inc., (Nasdaq:SPPI) announced that data on a field study with SPI-1620 in dogs with spontaneously occurring tumors were presented via poster presentation at the 2008 Annual Meeting of the American Association of Cancer Research (AACR), held in San Diego, California. SPI-1620, a highly selective endothelin-B receptor agonist, is being developed as an adjunct to cancer therapy. In earlier preclinical studies, SPI-1620 had demonstrated evidence of transiently enhancing the blood flow to tumors, thus increasing the delivery and efficacy of chemotherapeutic agents to tumors, sparing normal tissues.