Anifrolumab Added to the PBS

Anifrolumab has recently been added to the Pharmaceutical Benefits Scheme (PBS) for the treatment of systemic lupus erythematosus (SLE). To be eligible for PBS subsidy, patients must be receiving hydroxychloroquine, an immunosuppressant, and a corticosteroid unless contraindicated or intolerant.

Anifrolumab is a monoclonal antibody that binds with high affinity and specificity to the type I interferon receptor (IFNAR1). This inhibits type I interferon signalling, thereby blocking its biological activity. While SLE is complex and associated with many immunologic abnormalities, upregulation of type I interferon is thought to be a major pathogenic factor. In the phase 3 TULIP trials, anifrolumab was associated with improved overall disease severity, reduced glucocorticoid use, and a greater improvement in the severity of skin disease compared to placebo.

Anifrolumab is administered intravenously, typically as a 30-minute infusion every four weeks. The infusion rate may be reduced if infusion-related reactions occur. These reactions are typically mild or moderate in intensity and may include headache, nausea, vomiting, fatigue, or dizziness. In the case of a serious infusion-related or hypersensitivity reaction, immediate interruption of the infusion is required. Other potential adverse reactions include an increased risk of respiratory infections and herpes zoster. Treatment should not be initiated in patients with active infection, and caution is required in patients with chronic infection, recurrent infection, or known risk factors for infection.