The U.S. Food and Drug Administration has approved Sylvant (siltuximab) to treat patients with multicentric Castleman’s disease (MCD), a rare disorder (similar to lymphoma) that causes an abnormal overgrowth of immune cells in lymph nodes and related tissues. Sylvant is an injection that works by blocking a protein that stimulates the abnormal immune cell growth, and it is intended for patients who do not have HIV or human herpes virus 8 (HHV-8).
“Sylvant is the first FDA-approved drug to treat patients with MCD,” Richard Pazdur, MD, Director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, said in a news release. “Today’s approval demonstrates the FDA’s commitment to approving drugs for rare diseases.”
Sylvant was reviewed under the FDA’s priority review program, which provides for an expedited review of drugs that have the potential (at the time the application was submitted) to be a significant improvement in safety or effectiveness in the treatment of a serious condition. Sylvant was also granted orphan product designation because it is intended to treat a rare disease or condition.
The drug’s safety and effectiveness were evaluated in a clinical trial of 79 patients with MCD who were HIV and HHV-8 negative, who were randomly assigned to receive either Sylvant and best supportive care or placebo and best supportive care. The results, reported at the most recent American Society of Hematology Annual Meeting in December, showed that 34 percent of the patients treated with Sylvant and best supportive care experienced tumor response, while no participants treated with placebo and best supportive care did (OT 4/10/14 issue).
Common side effects reported include pruritus, weight gain, rash, increased levels of uric acid in the blook, and upper respiratory tract infection.
Sylvant is marketed by Janssen Biotech Inc.