RM-581

RM-581 is an orally active small molecule aminosteroid derivative currently in preclinical development by Neolys Pharma for the treatment of various refractory cancers, including pancreatic cancer, triple-negative breast cancer (TNBC), and castration-resistant prostate cancer (CRPC). Originally discovered at Laval University, the compound features a quinoline-proline-piperazine side chain attached to a mestranol core. RM-581 exerts its anticancer effects through a novel mechanism of action by inducing endoplasmic reticulum stress (ERS), which subsequently triggers apoptosis in tumor cells. This pathway is distinct from traditional cytotoxic agents and hormonal therapies, potentially offering a favorable safety profile and the opportunity for synergistic combinations with existing standards of care. In preclinical models, RM-581 has demonstrated potent activity, notably achieving complete tumor regression in pancreatic cancer xenografts.