Introduction: Proteasome inhibitors (PIs) are among the backbones of multiple myeloma (MM) treatment; however, their long-term use can be limited by parenteral administration and treatment-related toxicities. Ixazomib, the first oral PI to enter the clinic, is approved around the world, in combination with lenalidomide and dexamethasone, for the treatment of patients with MM who have received at least one prior therapy. Areas covered: This review summarizes the clinical data leading to approval of ixazomib; its pharmacology, efficacy, and safety. Building on the data in relapsed/refractory MM (RRMM), it also reviews the available clinical trial data for ixazomib across the MM treatment algorithm in newly diagnosed MM, RRMM, and as maintenance therapy, and looks ahead to ongoing clinical trials and the expanding role of ixazomib in these indications. Expert opinion: Ixazomib is an efficacious and well-tolerated addition to the treatment armamentarium for RRMM, with benefit as a long-term, continuous therapy for all patients, including ‘poor prognosis’ patients, such as those with advanced stage disease, high-risk cytogenetic abnormalities, and elderly and frail patients. Data from ongoing clinical studies are expected to expand the role of ixazomib across the MM treatment algorithm and in a broader range of combination regimens.