A group of Italian researchers recently showed that consolidation therapy with Velcade, thalidomide, and dexamethasone was more effective than consolidation therapy with thalidomide and dexamethasone alone.

In particular, they found that the Velcade-based consolidation therapy yielded more high-quality responses, such as complete responses, and a high rate of molecular remission, in which patients showed no signs of remaining myeloma cells.

Dr. Michele Cavo from the Seragnoli Institute of Hematology in Bologna, Italy, presented the results at the 16^th Congress of the European Hematology Association (EHA) in London last week.

In the study, Dr. Cavo and his colleagues randomly assigned 474 newly diagnosed myeloma patients to receive treatment with Velcade (bortezomib), thalidomide (Thalomid), and dexamethasone (Decadron) – known as VTD – or thalidomide and dexamethasone alone -- known as TD – as induction therapy prior to stem cell transplantation and again as consolidation therapy after stem cell transplantation.

Results from the induction therapy phase of the study showed that treatment with VTD was superior to treatment with only TD prior to stem cell transplantation; 31 percent of patients in the VTD treatment arm achieved a complete response or near-complete response, compared to 11 percent of patients in the TD treatment arm (see related Beacon news).

In the Myeloma Beacon’s survey of the most important myeloma-related findings in 2010, leading myeloma physicians and researchers ranked Dr. Cavo’s findings from the induction therapy phase as the second most important journal article (see related Beacon news).

Following induction therapy, patients underwent two sequential stem cell transplantations. All patients then received the same treatment they had received as induction therapy as two 35-day cycles of consolidation therapy.

Dr. Cavo and his colleagues found that the rate of complete response or near-complete response was significantly higher for patients who received consolidation therapy with VTD. After consolidation therapy, 62 percent of patients in the VTD treatment arm achieved a complete response or near-complete response, compared to 45 percent of patients in the TD treatment arm.

The researchers also found that patients who received VTD had a two-fold higher chance of an improved response after consolidation therapy than patients who received TD (11 percent versus 6 percent, respectively).

After consolidation therapy, the researchers also assessed the patients for signs of residual disease, which refers to traces of cancerous cells that remain after treatment. Residual disease, even a minimal amount, is the major cause of relapse in myeloma and many other types of cancer.

The researchers did not detect any residual disease in 64 percent of patients treated with VTD consolidation therapy, compared to 48 percent of patients treated with TD consolidation therapy.

They also found that patients without residual disease may have more favorable clinical outcomes. They estimated that 89 percent of patients with no detectable residual disease would be alive and disease-free at three years, compared to 47 percent of patients with residual disease.

The rate of serious side effects was comparable for both treatment arms (11 percent for VTD versus 10 percent for TD). The rates of severe peripheral neuropathy, a common side effect found with thalidomide- and Velcade-based regimens, were low (1 percent for VTD versus 0 percent for TD).

For more information, please see abstract 510 on the EHA website.