MRT-2359 + fulvestrant

MRT-2359 + fulvestrant is a combination therapy under clinical investigation for hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. MRT-2359 is an orally bioavailable small molecule molecular glue degrader that targets GSPT1, a translation termination factor, promoting its degradation through the ubiquitin-proteasome system and leading to cancer cell death in MYC-driven tumors[2][4][6]. Fulvestrant is a selective estrogen receptor degrader (SERD) that antagonizes and degrades estrogen receptor, inhibiting estrogen-mediated signaling in breast cancer. Early-phase trials are assessing the safety and efficacy of this combination, with MRT-2359 aiming to address resistance mechanisms encountered with endocrine therapy[4][6].