Phase 3 Trial Shows SB16 Biosimilar Comparable to Denosumab in Postmenopausal Osteoporosis
Overview
In a 12-month phase 3 randomized study involving 457 women with postmenopausal osteoporosis, SB16 demonstrated equivalent efficacy to reference denosumab in increasing lumbar spine bone mineral density (BMD). Secondary endpoints, pharmacokinetics, pharmacodynamics, safety, and immunogenicity profiles were also comparable, supporting SB16 as a biosimilar alternative.
Background
Postmenopausal osteoporosis (PMO) is a common chronic bone disease characterized by decreased bone mass and increased fracture risk. Denosumab, a monoclonal antibody targeting RANK ligand, reduces bone resorption and increases bone density. Biosimilars like SB16 are developed to match the reference biologic's quality, efficacy, and safety through rigorous comparability studies. This trial aimed to evaluate SB16's biosimilarity to denosumab in PMO patients over 12 months.
Data Highlights
Parameter
SB16
Denosumab
Difference (90% CI)
Percent change in lumbar spine BMD at 12 months (full analysis set)
Not specified
Not specified
0.33% (−0.25 to 0.91)
Percent change in lumbar spine BMD at 12 months (per-protocol set)
Not specified
Not specified
0.39% (−0.36 to 1.13)
Key Findings
The least-squares mean difference in percent change from baseline lumbar spine BMD at 12 months was 0.33% (90% CI, −0.25 to 0.91) in the full analysis set, within the predefined equivalence margin.
In the per-protocol set, the difference was 0.39% (95% CI, −0.36 to 1.13), also within equivalence margins.
Secondary endpoints including BMD changes at other skeletal sites, pharmacokinetics, and pharmacodynamics were comparable between SB16 and denosumab.
Safety and immunogenicity profiles showed no clinically meaningful differences between the two treatments.
SB16 demonstrated highly similar physicochemical and biological properties to denosumab in prior analytical and phase 1 studies.
Clinical Implications
SB16 offers a biosimilar treatment option to denosumab for postmenopausal osteoporosis, potentially increasing patient access and reducing costs. Clinicians can expect similar efficacy and safety profiles when prescribing SB16. Continued monitoring during longer-term use and switching phases remains important.
Conclusion
The 12-month data from this phase 3 trial support the biosimilarity of SB16 to reference denosumab in women with postmenopausal osteoporosis, demonstrating equivalent efficacy, safety, and immunogenicity.
by Bente Langdahl, Yoon-Sok Chung, Rafal Plebanski, Edward Czerwinski, Eva Dokoupilova, Jerzy Supronik, Jan Rosa, Andrzej Mydlak, Anna Rowińska-Osuch, Ki-Hyun Baek, Audrone Urboniene, Robert Mordaka, Sohui Ahn, Young Hee Rho, Jisuk Ban, Richard Eastell
