The B-lymphocyte stimulator–inhibitor called Benlysta already is approved for use in adults alongside standard therapy for SLE, and this approval marks the first such treatment available for children. Although there are regulatory submissions for use of this drug among children elsewhere, the United States is the first to approve its use among this age group, according to a press release from GSK. According to an FDA press announcement, the agency expedited the review and approval because belimumab could fulfill an unmet need.
The approval is based on a 1-year postapproval commitment study, which assessed efficacy, safety, and pharmacokinetics of 10 mg/kg belimumab plus standard therapy versus placebo plus standard therapy among children with SLE aged 5-11 years (n = 13) and those aged 12-17 years (n = 80). Although the study was not fully powered because of the rarity of the disease in this age group, it did find numerically higher SLE responder index response rates over 1 year among children treated with belimumab plus standard therapy (53%) than in those treated with placebo and standard therapy (44%).
Adverse reactions seen among this age group were consistent with those seen in adults, including nausea, diarrhea, pyrexia, nasopharyngitis, and bronchitis. The most common serious adverse reactions were serious infections. Belimumab has not been studied in combination with certain other drugs, such as other biologics or cyclophosphamide; therefore, combining it with such treatments is not recommended. Acute hypersensitivity reactions – including anaphylaxis and death – have been observed, even among patients who had previously tolerated belimumab.
Infusion reactions were common, so pretreat patients with an antihistamine. Also, do not administer the drug with live vaccines, the FDA noted.
More information can be found in the press announcement on the FDA website.