mTOR inhibitor + selective estrogen receptor modulator

This is a combination therapy consisting of an mTOR inhibitor and a selective estrogen receptor modulator (SERM). mTOR inhibitors, such as everolimus, temsirolimus, sirolimus, or ridaforolimus, target the mammalian target of rapamycin (mTOR) pathway—a key regulator of cell growth and proliferation implicated in cancer progression and resistance to endocrine therapies. Selective estrogen receptor modulators (SERMs), such as tamoxifen or raloxifene, bind to the estrogen receptor and block its activity in breast tissue while potentially acting as agonists in other tissues. The combination is primarily investigated for hormone receptor–positive breast cancer to overcome or delay resistance to endocrine therapy by targeting both the ER signaling axis and downstream proliferative pathways[1][2][4]. Preclinical studies have shown synergistic anticancer effects with this combination; clinical trials are ongoing.