BEYFORTUS

What it is

BEYFORTUS contains nirsevimab, a recombinant neutralising human IgG1κ long-acting monoclonal antibody to the prefusion conformation of the RSV F protein which has been modified with a triple amino acid substitution (YTE) in the Fc region to extend serum half-life. BEYFORTUS is available as a solution for injection in two strengths: 50 mg in 0.5 mL and 100 mg in 1 mL in prefilled syringes.

Approved indications

— Prevention of Respiratory Syncytial Virus (RSV) lower respiratory tract disease in neonates and infants born during or entering their first RSV season. — Prevention of Respiratory Syncytial Virus (RSV) lower respiratory tract disease in children up to 24 months of age who remain vulnerable to severe RSV disease through their second RSV season.

Dosing overview

For neonates and infants born during or entering their first RSV season, the recommended dosage is based on body weight and administered as a single intramuscular injection: 50 mg for infants weighing less than 5 kg, and 100 mg for those weighing 5 kg or greater. For children up to 24 months of chronological age who remain at increased risk for severe RSV disease in their second RSV season, the recommended dosage is 200 mg administered as two intramuscular injections (2 × 100 mg) at the same visit.

Key safety warnings

Serious hypersensitivity reactions have been reported following BEYFORTUS administration, including urticaria, dyspnoea, cyanosis, and/or hypotonia. If signs and symptoms of anaphylaxis or other clinically significant hypersensitivity reaction occur, immediately discontinue administration and initiate appropriate medicinal products and/or supportive therapy. BEYFORTUS should be given with caution to individuals with thrombocytopenia, any coagulation disorder or to individuals on anticoagulation therapy. In some individuals with protein-losing conditions, an increased clearance of nirsevimab was observed in clinical trials, and nirsevimab may not provide the same level of protection in individuals with significant protein loss.

Contraindications

BEYFORTUS is contraindicated in individuals with a history of severe hypersensitivity reactions, including anaphylaxis, to the active substance or to any of the excipients.

PBS listing

No information regarding PBS listing status is available in the provided documents.

Regulatory history

BEYFORTUS was registered on the Australian Register of Therapeutic Goods on 24 November 2023, with two strength variants listed: nirsevimab 50 mg in 0.5 mL and nirsevimab 100 mg in 1 mL solution for injection in prefilled syringes. The TGA approved BEYFORTUS for prevention of Respiratory Syncytial Virus lower respiratory tract disease in neonates and infants born during or entering their first RSV season, and in children up to 24 months vulnerable through their second RSV season, with approval dated 22 November 2023. The PBAC recommended not proceeding with this submission in July 2024. In May 2025, the PBAC deferred consideration of prevention of RSV lower respiratory tract disease in the approved population. BEYFORTUS remains subject to additional monitoring in Australia to allow quick identification of new safety information.