bortezomib + dexamethasone + decitabine

This is a combination regimen consisting of three drugs—bortezomib, dexamethasone, and decitabine—used in the treatment of multiple myeloma. - **Bortezomib** is a small molecule proteasome inhibitor that blocks the 26S proteasome, leading to cell cycle arrest and apoptosis in cancer cells. It is primarily used for multiple myeloma and mantle cell lymphoma[1]. - **Dexamethasone** is a synthetic glucocorticoid corticosteroid with anti-inflammatory and immunosuppressant properties; it also induces apoptosis in certain cancer cells and enhances the efficacy of other antimyeloma agents[2][6]. - **Decitabine** is a hypomethylating agent (a nucleoside analog) that inhibits DNA methyltransferase, resulting in DNA hypomethylation and reactivation of tumor suppressor genes. It has been studied as an adjunct to standard regimens for its potential to overcome drug resistance or enhance response rates[3]. The combination has been investigated as second-line therapy for relapsed or refractory multiple myeloma, particularly after failure or suboptimal response to prior treatments. The rationale behind this regimen includes synergistic effects on malignant plasma cells by targeting different cellular pathways involved in proliferation, survival, and epigenetic regulation[3].