Researchers have published new results showing that patients with relapsed or refractory multiple myeloma achieve a better response to treatment with Revlimid (lenalidomide) plus dexamethasone than to dexamethasone alone.  This finding holds for all patients, including those who have previously been treated with thalidomide (marketed as Thalomid).

The new results are based on pooled data from two randomized clinical trials involving more than seven hundred myeloma patients.  The patients had either relapsed multiple myeloma - disease that had initially responded to treatment but had begun to progress again - or refractory multiple myeloma - in which the disease failed to respond to initial treatment.

Researchers further divided patients into two groups: those who had previously received thalidomide, and those never treated with the drug.

In all patient groups, adding Revlimid to dexamethasone increased the overall response rate to treatment and slowed the progression of disease as compared to treatment with only dexamethasone.

Researchers had speculated that because thalidomide and Revlimid are chemically similar, patients previously treated with thalidomide might be resistant or otherwise unresponsive to Revlimid.  However, while individuals never exposed to thalidomide responded in greater number to the Revlimid + dexamethasone regimen, those previously treated with thalidomide also experienced a beneficial response.

Furthermore, even patients who had not initially responded or had grown resistant to thalidomide achieved a positive response.

Patients receiving dexamethasone with Revlimid experienced a higher rate of side effects than those receiving dexamethasone alone.  These included deep vein thrombosis, a type of clot formation in the body's deep veins, and neutropenia, a drop in white blood cell count that can increase the risk of infection.

The researchers' findings are published in the December, 2008 issue of Blood (full article).