Hand osteoarthritis (OA) is a prevalent and debilitating joint disorder that impairs daily functioning and quality of life. Current treatments are often inadequate in managing the symptoms and progression of the disease. The cytokine interleukin (IL)-17 has been implicated in the inflammatory processes associated with OA, making it a potential target for therapeutic intervention. This trial aims to evaluate the efficacy of vunakizumab, an IL-17A inhibitor, in reducing pain and improving functional outcomes in patients with erosive hand OA.

This multicentre, randomised, placebo-controlled, double-blind trial will enrol 150 participants aged 30–80 years with symptomatic erosive hand OA. Participants will be randomised in a 1:1 ratio to receive either vunakizumab 120 mg or placebo subcutaneously every 4 weeks for 24 weeks, with a loading dose injection period during the first 4 weeks. The primary outcome is the change in hand pain assessed by the Visual Analogue Scale at 28 weeks. Secondary outcomes include changes in physical function measured by the Functional Index for Hand Osteoarthritis, the Quick Disabilities of the Arm, Shoulder and Hand questionnaire and the Health Assessment Questionnaire, as well as changes in grip strength and radiographic and MRI evaluations of the hands.

Written informed consent will be obtained from all participants. The study was approved by the Ethics Committee of Shanghai Sixth People’s Hospital (2024–217) and will adhere to the Declaration of Helsinki. Research results will be published in peer-reviewed journals.

ChiCTR2500101031; https://www.chictr.org.cn/showproj.html?proj=264789.