Data Show Comparable Efficacy, Added Cost Benefit With Adalimumab Biosimilar vs Humira

Patients with ankylosing spondylitis may be able to get the same benefits as Humira (adalimumab) at a lower cost by using the biosimilar IBI303, based on real-world results from a hospital in China.1

Drawing on data from 106 patients treated between May 2020 and December 2023, the study highlights how biosimilars like IBI303 can ease financial pressure on patients and health care systems without sacrificing quality of care.

The retrospective analysis out of Shenzhen Luohu People’s Hospital in China adds to the growing body of real-world evidence showing that the adalimumab biosimilar IBI303 delivers comparable effectiveness to Humira while offering significant cost savings in the treatment of ankylosing spondylitis.

Ankylosing spondylitis is a chronic inflammatory disease that primarily targets the spine, often resulting in persistent pain and mobility issues. The condition affects an estimated 0.2% to 0.5% of the US population.2 Globally, its occurrence ranges from 0.4 to 14 new cases per 100,000 people each year. Symptoms typically begin early in adulthood, with the onset peaking in a person's 20s and 30s. A significant majority, around 80% of patients, experience symptoms by age 30 or younger, while only a small fraction (5%) will see symptoms emerge after age 45.

Adalimumab has been a mainstay in ankylosing spondylitis management, but the high cost of originator products such as Humira has posed major access challenges—especially in resource-constrained settings.1 Biosimilars offer a lower-cost alternative, but real-world data are essential to understanding their performance outside the controlled environment of clinical trials.

In this analysis, 38 patients received Humira and 68 received IBI303. The researchers looked at adalimumab retention rates at 52 weeks as the primary outcome. At 1 year, retention was higher in the IBI303 group (63%) than the Humira group (44%). IBI303 also showed stronger early retention at 24 weeks (82% vs 67%).

Safety outcomes were nearly identical. Just 2 patients in each group experienced mild infusion-related reactions, with no statistically significant differences between the arms.

Cost differences were notable. Median treatment costs were significantly lower for patients on IBI303 compared with those on Humira, both at 12 weeks ($762.20 vs $903.70; P = .042) and at 52 weeks ($2543.00 vs. $2982.30; P = .004). The data suggest IBI303 may be a more cost-effective option for long-term disease management.

According to the authors, IBI303 demonstrated not only comparable effectiveness and safety but also higher retention and lower overall cost—key considerations in chronic disease treatment.

Although this study was conducted in China, its implications are far-reaching. As the US health care system continues to wrestle with drug pricing and access, real-world data like these bolster the case for broader adoption of biosimilars. IBI303’s strong performance supports the notion that biosimilars aren’t just budget alternatives—they’re viable first-line options that can help expand access to care while controlling costs.

The study also provided insight into dosing, with data suggesting that a maintenance dose of 40 mg every 4 weeks may be sufficient for many patients, potentially offering further savings.

The authors concluded, “From a Chinese perspective, there is no difference in retention rate and safety between IBI303 and Humira in real-world use [in patients with ankylosing spondylitis], but because IBI303 has [a] lower price, it will lighten patients’ economic burden, and our drug exposure results can provide data support for tapering of biological therapy.”

References

1. Cheng X, Fu Z, Liu J, et al. Comparative real-world retention rate and safety of biosimilar IBI303 versus Humira in ankylosing spondylitis: a retrospective study. Medicine (Baltimore). 2025;104(26):e43010. doi:10.1097/MD.0000000000043010

2. Ankylosing spondylitis. Johns Hopkins Arthritis Center. Accessed July 17, 2025. https://www.hopkinsarthritis.org/arthritis-info/ankylosing-spondylitis/