Three phase I trials of the antiangiogenesis agent 'Endostatin' confirm that the genetically-engineered protein has low toxicity, is well tolerated and has pharmacokinetics similar to that reported in preclinical trials. Furthermore, 'Endostatin' has biological activity against solid tumours, researchers reported at the 11th NCI-EORTC-AACR*Symposium on New Drugs in Cancer Therapy [Amsterdam, The Netherlands; November 2000].'We look for certain things in phase I trials',explained Dr James Thomas from the University of Wisconsin Medical School, Madison, US,'and we saw all of these occur with endostatin'.The 3 trials, which are the first clinical trial results of the drug to be reported, involved 61 patients who had a variety of solid tumours. The patients were not receiving any medication aside from 'Endostatin', so researchers said that it seemed fair to attribute the promising results seen in the trials to the drug.