For more than four decades, the standard of care in elderly multiple myeloma patients over age 65 has been a combination of melphalan (a chemotherapy drug) and prednisone (a steroid). Yet, this regimen, known as MP, only achieves a five percent complete remission rate.

The advent of novel therapeutic agents has greatly improved treatment outcomes.

Multiple researchers have tested an MP plus thalidomide ^[1] (Thalomid) regimen, or MPT, and the majority of these studies have found that MPT yields superior complete remission (CR), very good partial remission (VGPR), and progression-free survival rates, as compared to MP alone.

A large, randomized trial has also compared MP with MP plus Velcade ^[2] (MPV), another novel therapeutic agent. Although the follow-up time is still short in this study, MPV yielded impressive CR and CR/VGPR rates of 35 percent and 45 percent, respectively. These rates are not only superior to MP alone, but also to the melphalan-prednisone-thalidomide regimen.

One reason Velcade may produce such high complete remission rates is because it, unlike some other agents, is effective even in poor-risk cytogenetic patients who usually experience less favorable treatment outcomes.

A preliminary study also tested MP plus Revlimid ^[3] (MPR), yielding impressive enough results to justify the large Phase III study currently occurring. Additionally, researchers have investigated combining Revlimid with both high and low doses of the steroid dexamethasone. These regimens produced overall CR/VGPR rates of 52 and 42 percent, respectively.

Despite the success of these new treatments, researcher Jean-Luc Harousseau, MD, emphasizes that many important questions remain unanswered. Researchers remain unsure which front-line therapy for elderly patients ultimately offers the best efficacy/toxicity ratio, and it is still unclear whether melphalan is actually a necessary treatment component.

In addition, a trial is currently evaluating the optimal duration of initial treatment -- either a fixed number of cycles or treatment until relapse or side effects. Although no study is presently underway, researchers also continue to question whether or not maintenance therapy is necessary once patients enter remission.

For more information, please see the full article in the American Society of Hematology’s 2008 Education Program Book, Hematology ^[4], and the related Beacon article ^[5] about treatment in young patients.