FDA Grants Interchangeability Designation to Ustekinumab-Aauz for Stelara

The FDA granted ustekinumab-aauz (Otulfi) interchangeability status to the reference product, ustekinumab (Stelara). Due to the new designation, pharmacists can substitute ustekinumab with the biosimilar at the pharmacy level, depending on their state laws.¹

Pharmacists can substitute ustekinumab with the biosimilar at the pharmacy level, depending on their state laws. | Image Credit: SNAB - stock.adobe.com

“Fresenius Kabi is pleased to receive this interchangeable designation for Otulfi, and we will continue to evaluate all possibilities in the development and commercialization of our biosimilar portfolio that help create access for patients and healthcare professionals to important, high-quality and affordable therapies,” Sang-Jin Pak, MD, president of Biopharma and member of the Fresenius Kabi Management Board, said in a news release.¹

The FDA approved ustekinumab-aauz in September 2024 as both a subcutaneous and intravenous formulation. It was approved to treat Crohn disease, ulcerative colitis, moderate to severe plaque psoriasis, and active psoriatic arthritis, which are indications of the reference product. Studies have not been conducted in patients younger than 6, so the product does not have safety and efficacy established for this age group. The most common adverse reactions include nasopharyngitis, upper respiratory tract infection, headache, fatigue, injection site erythema, abdominal pain, influenza, fever, diarrhea, fatigue, and nausea.^2-4

The biosimilar has been studied for adult plaque psoriasis, pediatric plaque psoriasis for patients aged 12 to 17 years, psoriatic arthritis, Crohn disease, and ulcerative colitis. For plaque psoriasis, the 45 mg and 90 mg doses of the biosimilar showed a 67% and 66%, respectively, Psoriasis Area Severity Index (PASI) 75 response and a Physician Global Assessment (PGA) of cleared or minimal at 59% and 61% compared with the placebo at 3% and 4%, respectively. In the second study, the 45 mg and 90 mg doses showed 67% and 76%, respectively, and 68% and 73%, respectively, compared to 4% for both measures with the placebo. For pediatrics, PGA of cleared or minimal was achieved by 69.4% of patients, and 80.6% and 61.1% were PASI 75 and 90 responders, respectively, compared with 5.4%, 10.8%, and 5.4%, respectively, with the placebo.⁴

The first ustekinumab biosimilar, ABP 654 (Wezlana), was approved in November 2024, followed by AVT04 (Uzpruvo) in 2024. Otulfi became the fourth biosimilar to Stelara approved in the US.⁵

REFERENCES

1. FDA Grants Interchangeable Designation to Fresenius Kabi’s biosimilar Otulfi (ustekinumab-aauz). News release. Fresenius Kabi. May 19, 2025. Accessed May 20, 2025. https://www.businesswire.com/news/home/20250519113313/en/FDA-Grants-Interchangeable-Designation-to-Fresenius-Kabis-biosimilar-Otulfi-ustekinumab-aauz

2. Fresenius Kabi and Formycon Receive U.S. FDA Approval for Biosimilar Otulfi (ustekinumab-aauz). News release. Fresenius Kabi. September 30, 2024. Accessed May 20, 2025. https://www.fresenius-kabi.com/news/fresenius-kabi-and-formycon-receive-us-fda-approval-for-biosimilar-otulfi

3. Mayo Clinic. Ustekinumab-aauz (intravenous route, subcutaneous route). Updated April 1, 2025. Accessed May 20, 2025. https://www.mayoclinic.org/drugs-supplements/ustekinumab-aauz-intravenous-route-subcutaneous-route/description/drg-80002775

4. Otulfi [package insert]. Fresenius Kabi. 2024. https://www.biospecialized.com/wp-content/uploads/2023/03/prescribing-information-otulfi-US.pdf

5. Ferreri D. Future Directions for Ustekinumab Biosimilars in Crohn Disease. The Center for Biosimilars. May 3, 2025. Accessed May 20, 2025. https://www.centerforbiosimilars.com/view/future-directions-for-ustekinumab-biosimilars-in-crohn-disease