What is Bortezomib for: This medication is an antineoplastic agent, prescribed for multiple myeloma and mantle cell lymphoma. It works by killing cancer cells. How does Bortezomib work: Bortezomib harms cancer cells causing their death. How should Bortezomib be used: It comes as a solution for injection to be administered by a healthcare provider into the vein. Adult: IV- 1.3 mgm2 as bolus on days 1, 4, 8 and 11 of a 21-day cycle, followed by a 10-day rest period (days 12-21).