Purpose: After decades of minimal progress, two new classes of drugs with novels mechanisms of action: immunomodulatory drugs (thalidomide and lenalidomide) and proteasome inhibitors (bortezomib) have shown great activity for the treatment of multiple myeloma.
Current knowledge and key points: Thalidomide acts by a variety of mechanisms; its efficacy is well known in disease relapse especially associated with dexamethasone. Recent results prove that combination of thalidomide with melphalan and prednisone should be considered as the first line standard of care in elderly patient. The main side effects are peripheral neuropathy and deep-vein thrombosis. Bortezomib is the first proteasome inhibitor. It is approved for the treatment in first disease relapse. The combination with glucocorticoids is synergistic. This combination in induction treatment before autologous stem cell transplantation is promising, as well as the combination with melphalan and prednisone in elderly patient. The main toxicities are fatigue and peripheral neuropathy. Lenalidomide is a structural analogue of thalidomide. Its efficacy in combination with dexamethasone has been proved in relapsing patients. The main toxicity is hematologic. Utilisation as first line treatment is also promising.
Future prospects and projects: These three drugs have toxicities predictable and manageable and can be used successively or in combination for greater effectiveness. They have an impact on the multiple myeloma treatment strategies and on the disease course itself.