abt-510 abt-510 abt-510 is a molecular therapeutic drug that was the subject of research as a potential treatment for cancer. according to the journal of clinical oncology, abt-510 is a "subcutaneously (sc) administered nonapeptide thrombospondin analogue." following inconclusive phase i clinical trials, a 2007 phase ii study of abt-510 for treatment of metastatic melanoma failed to reach its primary endpoint resulting in termination of the study. only three out of twenty-one patients reached the primary endpoint of progression-free survival at 18 weeks, but these three patients remained progression-free for 21, 34, and 42 weeks. however, biomarker data collected during this study showed a decrease in vegf-c, circulating endothelial cells, and cd146 and cd34/133 counts, and a maximum tolerated dose has still not been established. further study could consider a higher dose and/or combination treatment.