Treatment of multiple myeloma in the targeted therapy era

To review the clinical trials that have impacted treatment standards of multiple myeloma (MM).

A PubMed search (1980-June 2008) restricted to English-language publications was conducted using the key words multiple myeloma, clinical trials, targeted therapy, thalidomide, lenalidomide, bortezomib, dexamethasone, melphalan, autologous stem-cell transplantation, and tumor biology. Abstracts emanating from the meetings of the American Society of Clinical Oncology and American Society of Hematology from June 2002 to June 2008 were also reviewed.

Although hematopoietic stem-cell transplantation has improved the response rate and duration of overall survival, MM remains an incurable disease. However, focused research aimed at the molecular basis of the disease has led to a number of new treatment strategies. Evidence from clinical trials indicates that each of the 3 novel agents, thalidomide, lenalidomide, and bortezomib, is remarkably effective as first-line therapy. The data also suggest that clinicians may need to reevaluate the role of stem-cell transplantation in the disease.

Thalidomide, lenalidomide, or bortezomib in combination with dexamethasone have replaced traditional chemotherapy such as melphalan, doxorubicin, and vincristine as initial therapy of patients with MM who are eligible for stem-cell transplantation. Furthermore, these novel drugs can be incorporated into regimens used to treat transplant-ineligible patients or those with relapsing disease.