“…The most active SERDs share common chemical features: either (a) a steroidal backbone (e.g., fulvestrant, RU58,668) or (b) an acrylic acid side chain (GW7604, GDC-0810, AZD9496) [29,31,32,40,56,57]. Additional ER antagonists with novel chemical structures have also been reported to exhibit SERD properties [35,36,58], but none has yet gained FDA approval and some have been discontinued due to adverse effects or for undisclosed reasons [29-36, 40, 56]. We have identified a novel, orally bioavailable SERD, G1T48, that contains both a steroidal backbone and an acrylate side chain.…”