Pooling results from two clinical trials, researchers have announced that Revlimid (lenalidomide) may bolster the immune systems of multiple myeloma patients, thereby helping to reduce dangerous infections.

Myeloma impairs the quality and quantity of antibodies - the “soldiers” of the immune system – that an individual produces. As a result, more than 75 percent of myeloma patients will experience marked immune system depression, becoming vulnerable to potentially life-threatening bacterial infections.

Recurrent bacterial infection, resulting primarily from this immune system depression, is the most frequent cause of death in myeloma patients with advanced disease.

In the current study, researchers analyzed data from two clinical trials to determine whether Revlimid, in addition to reducing tumor burden, could improve immune system function. At the beginning of each study, baseline levels of the antibodies IgA, IgG, and IgM were measured and evaluated monthly as treatment progressed.

In patients who received Revlimid, 56 and 50 percent of the respective study participants experienced significant improvement and normalization of their IgA antibody levels. IgG and IgM levels, however, remained unchanged. “Improvement” required both an increase of at least 25 percent in healthy, functional antibody and a final value that resided within normal range.

Significantly, only those patients whose myeloma positively responded to Revlimid experienced the normalization of their IgA antibodies. As expected, these patients enjoyed longer progression-free and overall survival than individuals who did not respond to Revlimid therapy.

These findings reveal that Revlimid may improve patient survival through both combating myeloma itself and increasing patients’ ability to fight off secondary infections.

Because vaccines require robust immune system response post-injection in order to confer protection, prophylactic vaccinations (such as for bacterial pneumonia) are usually unsuccessful in myeloma patients. By improving immune system function, however, Revlimid could potentially increase vaccination effectiveness in at-risk myeloma patient populations.

For more information, see abstract 0395 from the “Myeloma and other monocolonal gammopathies - Clinical I” session of the 14th Congress of the EHA.