The combination therapy of cyclophosphamide, thalidomide (Thalomid) and dexamethasone (Decadron), commonly referred to as CTD, is effective and well tolerated in newly diagnosed multiple myeloma patients, according to a new study published in the journal Clinical Lymphoma, Myeloma & Leukemia. Patients who underwent autologous stem cell transplantation (ASCT) after CTD therapy had higher success rates and longer survival.

Currently, thalidomide plus dexamethasone is one of the standard treatments for newly diagnosed myeloma patients. However, this treatment is associated with a high rate of blood clotting in the deep veins and negative effects on stem cell mobilization.

In their study, the researchers evaluated the patients’ response to CTD therapy. They also tested whether autologous stem cell transplantation following CTD treatment enhanced response and survival.

The researchers recruited 68 newly diagnosed myeloma patients under the age of 70 years. The median age of the participants was 62.6 years.

Patients received cyclophosphamide (150 mg/m² orally on days 1-4), thalidomide (400 mg orally on days 1-5 and 15-19), and dexamethasone (20 mg/m² intravenously on days 1-5 and 15-19) in 28-day treatment cycles. The median number of cycles administered was 5.7, ranging from 1 to 8 cycles.

After four cycles of therapy, 32.3 percent of patients achieved a complete response, 15.4 percent achieved a very good partial response, and 40 percent achieved a partial response, for an overall response rate of 87.7 percent. Three patients were not evaluated because they died during the third cycle of treatment.

Patients who responded well after four or more cycles of treatment, continued on to ASCT; 48.3 percent of patients experienced a complete response, and 20.7 percent of patients experienced a very good response. The overall response rate increased to 96.6 percent after ASCT. Overall survival and the time to progression were better for the patients who underwent ASCT than those who did not.

Severe side effects included low platelet count (13 percent), low white blood cell count (10 percent), and low red blood cell count (4 percent). The most common non-blood related side effects were nerve damage to the limbs (14 percent) and infections (10 percent).

The authors of the study concluded that the CTD regimen was effective and well tolerated as first-line therapy in newly diagnosed myeloma patients, resulting in a high success rate of stem cell mobilization and prolonged survival for patients who underwent ASCT.

For more information, see the study in the journal Clinical Lymphoma, Myeloma & Leukemia or the clinical trial listing from ClinicalTrials.gov.