FDA Approves Celltrion's Avtozma as Third Tocilizumab Biosimilar

The FDA approved Avtozma, a tocilizumab biosimilar developed by Celltrion, for the treatment of several rheumatic conditions.¹ It is the third biosimilar to reference Actemra (tocilizumab) to be approved for US patients.²

Avtozma (CT-P47, tocilizumab-anoh), was approved in intravenous (IV) and subcutaneous (SC) formulations and is indicated to treat rheumatoid arthritis (RA), giant cell arteritis (GCA), polyarticular juvenile idiopathic arthritis (pJIA), systemic juvenile idiopathic arthritis (sJIA), and COVID-19.

Tocilizumab products are used to treat rheumatoid arthritis, giant cell arteritis, polyarticular juvenile idiopathic arthritis, systemic juvenile idiopathic arthritis and COVID-19. | Image credit: Evrymmnt - stock.adobe.com

"Introducing both IV and SC formulations of AVTOZMA provides flexibility and a wider range of treatment options," said Thomas Nusbickel, Chief Commercial Officer at Celltrion USA. "Our goal is to provide safe and effective alternatives and ensure appropriate access so plan sponsors can address unique population needs."

The approval comes after those for Biogen and Bio-Thera Solutions' Tofidence (tocilizumab-bavi) in September 2023 and Fresenius Kabi's Tyenne (tocilizumab-aazg) in March 2024.^3,4

Upon launch, the IV formulation will come in doses of 80 mg/4 mL (20 mg/mL), 200 mg/10 mL (20 mg/mL), 400 mg/20 mL (20 mg/mL), and the SC version will come as a 162 mg/0.9 mL dose in a single-dose prefilled syringe or single-dose autoinjector.

The approval was based on data from a 52-week phase 3 randomized clinical trial (NCT05489224) assessing the efficacy, pharmacokinetics, safety, and immunogenicity of CT-P47 in comparison with Actemra. The researchers also assessed switching safety.⁵

The study included data on 471 patients with moderate to severe RA who had an inadequate response to at least 1 disease-modifying antirheumatic drug. Patients were randomized (1:1) to receive 8 mg/kg of either CT-P47 or reference tocilizumab intravenously every 4 weeks up to week 20. At week 24, 444 patients were re-randomized to either continue their original treatment or switch from reference tocilizumab to CT-P47, continuing treatment until week 48, followed by a 4-week follow-up period.

Of the rerandomized patients, 412 (92.8%) completed the study. The mean change in disease activity scores remained consistent across groups after the transition, with sustained clinical improvements up to week 52. Response rates and remission rates were comparable between groups.

The mean pre-dose serum drug concentrations at week 52 were similar across the CT-P47 group, the reference group, and the switched group (16.73 μg/mL, 17.41 μg/mL, and 17.32 μg/mL, respectively). Safety profiles from weeks 24 to 52 were comparable, with no new safety concerns. Immunogenicity rates were low and similar across groups, with 4.4% to 4.6% of patients developing antidrug antibodies and 1.8% developing neutralizing antibodies.

References

1. U.S. FDA approves Celltrion's Avtozma (tocilizumab-anoh), a biosimilar to Actemra^®. Press release. Celltrion USA; January 30, 2025. Accessed January 31, 2025. https://www.prnewswire.com/news-releases/us-fda-approves-celltrions-avtozma-tocilizumab-anoh-a-biosimilar-to-actemra-302364951.html

2. Biosimilars approvals. The Center for Biosimilars^®. Updated January 31, 2025. Accessed January 31, 2025. https://www.centerforbiosimilars.com/biosimilar-approvals

3. Jeremias S. FDA approves first tocilizumab biosimilar. The Center for Biosimilars. October 5, 2023. Accessed January 31, 2025. https://www.centerforbiosimilars.com/view/fda-approves-first-tocilizumab-biosimilar

4. Jeremias S. FDA green lights second tocilizumab biosimilar. The Center for Biosimilars. March 7, 2024. Accessed January 31, 2025. https://www.centerforbiosimilars.com/view/fda-green-lights-second-tocilizumab-biosimilar

5. Burmester G, Trefler J, Racewicz A, et al. Similar efficacy, PK, safety, and immunogenicity of tocilizumab biosimilar (CT-P47) and reference tocilizumab in patients with moderate-to-severe active rheumatoid arthritis: week 52 results from the phase III single transition study. Presented at: ACR Convergence 2024; November 14-19, 2024; Washington, DC. Accessed January 31, 2025. https://acrabstracts.org/abstract/similar-efficacy-pk-safety-and-immunogenicity-of-tocilizumab-biosimilar-ct-p47-and-reference-tocilizumab-in-patients-with-moderate-to-severe-active-rheumatoid-arthritis-week-52-results-from-the/