FDA Approves Ustekinumab-stba for All Forms & Dosages as Its Reference Product

On June 15, the U.S. Food & Drug Administration (FDA) approved a 45 mg/0.5 mL single-dose vial of ustekinumab-stba (Steqeyma) for subcutaneous injection for the treatment of plaque psoriasis or psoriatic arthritis (PsA) in pediatric patients weighing less than 60 kg and aged 6 to 17 years old.¹

This approval expands the drug’s dosing flexibility for pediatric patients. Additionally, ustekinumab-stba is now available in the same dosage forms and strengths as its reference product, ustekinumab (Stelara).

The FDA initially approved ustekinumab-stba as biosimilar to and interchangeable with ustekinumab for the same indications on Dec. 17, 2024. The agent is available for intravenous (IV) infusion and in prefilled syringes of 45 mg/0.5 mL and 90 mg/mL for subcutaneous injections.²

Ustekinumab & Its Biosimilars

Ustekinumab is a human interleukin (IL) 12 and IL-23 antagonist, anti-inflammatory agent, given by subcutaneous injection or IV infusion and administered at least every four weeks for the treatment of psoriasis and PsA.

In September 2009, the FDA approved the biologics license application for ustekinumab for the treatment of adults with moderate to severe plaque psoriasis who were candidates for phototherapy or systemic therapy.³ As of November 2024, the agent was subsequently FDA approved for the treatment of adults with active PsA, moderate to severe active Crohn’s disease and/or moderate to severe active ulcerative colitis. ⁴

Ustekinumab is also FDA approved for the treatment of pediatric patients 6 years of age and older with moderate to severe plaque psoriasis who are candidates for phototherapy or systemic therapy, and/or those with active PsA.⁴

In addition to ustekinumab-stba, FDA has approved six other medications as biosimilar to, and interchangeable with, ustekinumab. They are:

• Ustekinumab-aauz (Otulfi) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL) and for IV infusion;
• Ustekinumab-ttwe (Pyzchiva) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL) and for IV infusion;
• Ustekinumab-aekn (Selarsdi) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL) and for IV infusion;
• Ustekinumab-hmny (Starjemza) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL) and for IV infusion;
• Ustekinumab-auub (Wezlana) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL), auto-injectors (45 mg/0.5 mL and 90 mg/mL) and for IV infusion; and
• Ustekinumab-kfce (Yesintek) as a single-dose vial (45 mg/0.5 mL), prefilled syringes (45 mg/0.5 mL and 90 mg/mL) and for IV infusion.⁵

Michele B. Kaufman, PharmD, BCGP, is a freelance medical writer based in New York City and a pharmacist at New York Presbyterian Lower Manhattan Hospital.

References

1. Celltrion announces U.S. FDA approval of additional presentation of Steqeyma (ustekinumab-stba), expanding dosing options for pediatric patients [news release]. Celltrion Inc. 2025 Jun 16.
2. Biologics license application approval letter: Steqeyma (ustekinumab-stba). U.S. Food & Drug Administration. 2024 Dec 17.
3. Biologics license application approval letter: Stelara (ustekinumab). U.S. Food & Drug Administration. 2009 Sep 25.
4. Highlights of subscribing information: Stelara (ustekinumab). U.S. Food & Drug Administration. 2024 Nov.
5. Purple Book: Database of licensed biologic products. Ustekinumab. U.S. Food & Drug Administration. 2025.