The U.S. Food and Drug Administration approved an expanded indication for tocilizumab-anoh (Avtozma; Celltrion) IV formulation on August 6, 2025, to treat cytokine release syndrome (CRS) in adults and pediatric patients aged 2 years and older. This approval marks a significant milestone as tocilizumab-anoh IV now aligns with all indications approved for its reference drug, tocilizumab (Actemra; Genentech).
Biosimilar Achieves Full Indication Parity
Tocilizumab-anoh, containing the active ingredient tocilizumab, is a recombinant humanized monoclonal antibody that acts as an interleukin 6 (IL-6) receptor antagonist. The CRS expanded label approval follows the approval of several indications for tocilizumab-anoh on January 31, 2025, including polyarticular juvenile idiopathic arthritis (pJIA), systemic juvenile idiopathic arthritis (sJIA), rheumatoid arthritis, giant cell arteritis, and COVID-19.
"We are proud that [tocilizumab-anoh IV] has now achieved full indication alignment with the reference [tocilizumab-anoh IV]. This milestone marks an important step forward in our mission to deliver a safe and effective therapy for CRS," said Thomas Nusbickel, chief commercial officer at Celltrion USA. "This FDA approval expands access to high-quality biologics and supports beneficial patient outcomes across multiple therapeutic areas."
Understanding Cytokine Release Syndrome
CRS is a potentially life-threatening condition that occurs when the immune system is highly activated, leading to the rapid and excessive release of cytokines into the bloodstream. During a cytokine storm, the overactivated immune system can cause widespread inflammation and damage to healthy tissue and organs throughout the body. Symptoms can range from mild, flu-like symptoms to more severe complications such as low blood pressure, difficulty breathing, multi-organ failure, and death.
Clinical Evidence Supporting Approval
The January 2025 approvals of tocilizumab-anoh were based on a comprehensive data package and totality of evidence that included results from a phase 3 study demonstrating biosimilarity between tocilizumab-anoh and reference tocilizumab in patients with moderate-to-severe active rheumatoid arthritis.
In the trial, the primary endpoint, change from baseline in disease activity score using 28 joints at week 24, was met. The final 1-year results supported comparability in secondary efficacy, pharmacokinetics, and safety and immunogenicity results between tocilizumab-anoh and the reference. Results demonstrated that the biosimilar and reference are "highly similar and have no clinically meaningful differences in terms of efficacy, safety, pharmacokinetics and immunogenicity," according to Celltrion.
Market Availability and Patent Considerations
In accordance with the patent settlement agreement with Genentech, the IV formulation of AVTOZMA is expected to be available in the United States on August 31, 2025. Celltrion holds a license to market the subcutaneous formulation in the United States commencing on the licensed launch date, which remains confidential.
Comprehensive Indication Portfolio
The tocilizumab-anoh biosimilar now carries approvals for multiple conditions in both IV and subcutaneous formulations, including:
- Polyarticular juvenile idiopathic arthritis in patients 2 years and older with active pJIA
- Systemic juvenile idiopathic arthritis in patients aged 2 years and older with sJIA
- COVID-19 in hospitalized adult patients receiving systemic corticosteroids and requiring supplemental oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation
- Giant cell arteritis in adult patients
- Rheumatoid arthritis in adults with moderately to severely active RA who have had an inadequate response to one or more Disease-Modifying Anti-Rheumatic Drugs
- Cytokine release syndrome in adults and pediatric patients 2 years and older
This expanded indication represents Celltrion's continued commitment to providing access to high-quality biosimilar therapeutics across multiple therapeutic areas, potentially offering cost-effective treatment options for patients with serious inflammatory and immune-mediated conditions.
