New Orleans, LA—An investigational monoclonal antibody may be of benefit in treating patients with multicentric Castleman’s disease, a potentially fatal, incurable disorder with high morbidity believed to be partially mediated by the overproduction of interleukin-6 that results in the dangerous overgrowth of cells in the lymph nodes. The drug, siltuximab, blocks the function of interleukin-6 and ideally ameliorates this uncontrolled cell growth and controls other inflammatory disease symptoms.
In a phase 2 study presented at ASH 2013, and featured in a press briefing, investigators randomly assigned 70 patients with multicentric Castleman’s disease to siltuximab or to placebo, plus best supportive care. Of the patients treated with siltuximab, 34% achieved a durable tumor and symptom response compared with none of the patients in the placebo arm.
At baseline, patients reported fatigue (86%), malaise (61%), night sweats (52%), peripheral sensory neuropathy (38%), anorexia (37%), and pruritus (37%). The symptoms completely resolved in 25% of the siltuximab group for a median of 1.3 years, but placebo recipients had no resolution of symptoms. The median time to next treatment was not reached in the siltuximab arm versus a time of 280 days in the placebo arm.
Despite a 2-fold longer duration of treatment with siltuximab, rates of adverse events were similar between the arms, reported Raymond S. Wong, MBChB, MD, a radiation oncologist at the Prince of Wales Hospital, Chinese University of Hong Kong, China.
“If siltuximab gains regulatory approval, this experimental therapy could become the first globally approved treatment for this incurable disease and could potentially transform how patients are treated in the future,” Dr Wong predicted.