gataparsen gataparsen gataparsen (development code ly2181308) is an antisense oligonucleotide that complementarily binds to survivin mrna and inhibits its expression in tumor tissue. gataparsenclinical dataother namesly2181308legal statuslegal status investigational identifierscas number1065019-70-6unii895o8qkf18 it being investigated for a number of different cancers. it is targeted at survivin which prevents cells dying. clinical trials it has completed a phase ii trial for acute myeloid leukemia. a phase ii trial for non-small cell lung cancer has started. a phase ii trial for hormone-refractory prostate cancer will run until early 2012.