- CDB-4124 and its putative monodemethylated metabolite, CDB-4453, are potent antiprogestins with reduced antiglucocorticoid activity: in vitro comparison to mifepristone and CDB-2914. Attardi, B.J., Burgenson, J., Hild, S.A., Reel, J.R., Blye, R.P. Mol. Cell. Endocrinol. (2002)