nab-sirolimus + exemestane

nab-sirolimus + exemestane is an investigational combination regimen of two drugs: nab-sirolimus (an albumin-bound nanoparticle formulation of sirolimus, an mTOR inhibitor) and exemestane (a steroidal aromatase inhibitor). Nab-sirolimus inhibits the mammalian target of rapamycin (mTOR), a serine/threonine kinase involved in cellular growth, proliferation, and survival signaling; exemestane blocks the aromatase enzyme to reduce estrogen synthesis, suppressing hormone-receptor-driven breast cancer cell proliferation. This combination is investigated for enhanced antitumor activity compared to either agent alone, primarily for advanced hormone receptor-positive cancers. Nab-sirolimus is being studied in various cancers and shows promising activity in malignancies with mTOR pathway activation.