FDA Approves Seventh Ustekinumab Biosimilar

The FDA has approved Celltrion’s CT-P43/ustekinumab-stba under the name Steqeyma, an ustekinumab biosimilar, for subcutaneous injection or intravenous infusion for both adult and pediatric patients with plaque psoriasis (PsO) and active psoriatic arthritis (PsA) as well as adults with Crohn disease (CD) and ulcerative colitis (UC).1 CT-P43 is expected to launch in February 2025.

"The approval of STEQEYMA reflects Celltrion's continued investment in providing treatment options to patients diagnosed with ulcerative colitis, Crohn's disease, psoriasis, and psoriatic arthritis," Thomas Nusbickel, Chief Commercial Officer, Celltrion USA, said in a statement.1 "STEQEYMA is now the latest biologic in our immunology portfolio, joining ZYMFENTRA® (infliximab-dyyb). Our portfolio, supported by our fully integrated platform, establishes Celltrion USA as an important player in the U.S. immunology market."

The FDA approval of STEQEYMA was based on the totality of evidence, including the results from a phase III study in adults with moderate to severe plaque psoriasis, in which the primary endpoint was the rate of change in the Psoriasis Area and Severity Index (PASI) for skin symptoms. The clinical results demonstrated that STEQEYMA and its reference product, ustekinumab, are highly similar, and have no clinically meaningful differences in terms of safety and efficacy.

CT-P43 was approved based on evidence from a phase 3 trial which provided evidence of equivalent efficacy to originator ustekinumab, with comparable pharmacokinetic, safety, and immunogenicity profiles in over 500 patients.

The trial was led by Kim Papp, MD, PhD, president of Probity Medical Research Inc, and her team wholaunched a double-blind, randomized phase 3 trial comparing CT-P43 against ustekinumab in adult patients with moderate to severe plaque psoriasis from 34 centers in Estonia, Poland, Republic of Korea, and Ukraine.2

Upon analysis, mean percent improvements in PASI score at week 12 were 77.93% for the CT-P43 cohort and 75.89% for the originator ustekinumab cohort using the FDA approach. Using the EMA approach, the corresponding values were 78.26% and 77.33%, respectively. Further analysis suggested the estimated treatment differences were 2.05 (90% CI, -0.23 to 4.32) and 0.94 (95% CI, -2.29 to 4.16), with investigators noting equivalence was achieved for both sets of assumptions. Investigators also highlighted additional efficacy parameters and pharmacokinetic, safety, and immunogenicity outcomes were comparable between treatment groups, including after switching from originator ustekinumab to CT-P43.2

Ustekinumab-stba marks the seventh ustekinumab biosimilar to get FDA approval. Ustekinumab is a fully human monoclonal antibody that selectively inhibits both interleukin (IL)-12 and IL-23 and was originally approved over a decade ago for moderate to severe plaque psoriasis in adult patients.

"Plaque psoriasis and psoriatic arthritis are both autoimmune disorders that affect the skin and present differently in all patients," Mark G. Lebwohl, MD, Icahn School of Medicine at Mount Sinai, New York, added.2 "The approval of new treatment option is welcome news for people living with certain chronic inflammatory conditions, such as psoriasis, which affect more than 3% of the US adult population."

REFERENCES

1. U.S. FDA approves Celltrion's STEQEYMA® (ustekinumab-stba), a biosimilar to STELARA® (ustekinumab). News release. Celltrion. December 17, 2024. https://www.prnewswire.com/news-releases/us-fda-approves-celltrions-steqeyma-ustekinumab-stba-a-biosimilar-to-stelara-ustekinumab-302334458.html

2. Papp KA, Lebwohl MG, Thaçi D, et al. Efficacy and Safety of Candidate Biosimilar CT-P43 Versus Originator Ustekinumab in Moderate to Severe Plaque Psoriasis: 28-Week Results of a Randomised, Active-Controlled, Double-Blind, Phase III Study. BioDrugs. Published online November 22, 2023. doi:10.1007/s40259-023-00630-5