An Efficacy and Safety Study of Subcutaneous Anakinra in Chinese Patients With Systemic Juvenile Idiopathic Arthritis (SJIA) and Adult-Onset Still's Disease (AOSD)

A Prospective, Open-label, Multicenter, Post-authorization, Efficacy and Safety Study of Subcutaneous Anakinra in Chinese Patients With Systemic Juvenile Idiopathic Arthritis (SJIA) and Adult-Onset Still's Disease (AOSD)

The purpose of this study is to evaluate the efficacy and safety of anakinra in Chinese patients with Systemic Juvenile Idiopathic Arthritis (SJIA) and Adult-Onset Still's Disease (AOSD).The study consists of up to four weeks screening, to see if a patient is suitable to the study, 48 weeks of treatment with anakinra and 4 weeks safety follow up after last dose of anakinra. In total 60 patients(expected allocation is 30 SJIA and 30 AOSD), male or female patients, 8 months of age or older with a body weight ≥ 10 kg, will be enrolled to the study.

Study Overview

• Status: Withdrawn
• Conditions: Systemic Juvenile Idiopathic Arthritis (sJIA); Adult Onset Still's Disease (AOSD)
• Intervention / Treatment: Drug: Anakinra (Kineret®)

Detailed Description

This is a prospective, open-label, multicenter, efficacy and safety study of anakinra in Chinese patients with Still's disease (SJIA and AOSD). The study consists of a 48-Week treatment period with anakinra followed by a 4-Week period to evaluate safety of anakinra after the last dose of IMP. The study is divided into three parts: screening, treatment period, and safety follow-up, and will be performed in China.

The study will recruit a total of 60 patients (expected allocation is 30 SJIA and 30 AOSD).

The patient will enter screening after informed consent is obtained and will undergo screening assessments to confirm eligibility. Duration of the screening period will be kept as short as possible and should not exceed 4 weeks.

Patients will be assigned to study drug after they have met all of the inclusion criteria and none of the exclusion criteria. Patients will receive treatment with anakinra for 48 weeks.

After the last dose of anakinra at Week 48, the safety will continue to be evaluated at a Safety Follow-up visit i.e., at Week 52.

14 visits and 1 telephone contact are scheduled during the study as follows: Screening visit (Visit 0), Day 1 (Baseline visit), Day 4Tel, Week 1, Week 2, Week 4, Week 8, Week 12, Week 16, Week 20, Week 24, Week 32, Week 40, Week 48 (last dose of anakinra), and Week 52 (end of study).

All patients included in the study will be carefully monitored by the investigator. Patients can withdraw from the study drug at any time for any reason. If a patient permanently discontinues study drug, at any time during the study prior to week 48, a Study Drug Discontinuation visit should be performed, if possible before standard of care treatment is initiated. If clinically not feasible, the Study Drug Discontinuation visit should be performed as soon as possible.

4 weeks after discontinuation of study drug, a subsequent Safety Follow-up visit will be performed, according to the assessments described for the Week 52 visit, after which the patient will be withdrawn from the study.

• Study Type: Interventional
• Phase: Phase 4

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Informed consent form signed by the patient or a legal guardian representative.
2. Male or female patients, 8 months of age or older with a body weight ≥ 10 kg.
3. Diagnosis of Still's disease.

4. Criteria for diagnosis of Still's disease:

   1. If < 16 years of age at disease onset, the diagnosis is made according to international league for associations of rheumatology (ILAR) criteria for SJIA.
   2. If ≥ 16 years of age at disease onset, the diagnosis is made according to Yamaguchi criteria for AOSD.

5. Active disease confirmed by the following three signs and symptoms:

   1. Active arthritis in ≥ 1 joint.
   2. CRP > 30 mg/L.
   3. At least one fever episode attributable to the disease within one week before enrollment.

   Definition of fever: Body temperature ≥ 38.0 °C attributable to the disease

6. Background treatment with stable dose of ≤ 1 mg/kg/d (Max 60 mg/d) of oral prednisolone or equivalent for at least 3 days prior to enrollment is permitted.
7. If currently on methotrexate (MTX) treatment, the dose must be stable for at least 4 weeks prior to enrollment. Maximum dose allowed is 20 mg/m2/week. If the patient discontinued MTX prior to enrollment, the discontinuation is required to be at least 4 weeks prior to enrollment.
8. Female patients of childbearing potential and male patient with female partner of childbearing potential must use an effective method of contraception during the study (abstinence being a possible option). A negative pregnancy test prior to enrollment is also required.
9. In case of use of oral contraception, women should have been stable on the same brand (or generic equivalent) for a minimum of 3 months before taking study treatment.
10. Negative tuberculosis screening confirmed at the Screening visit by the Mantoux Tuberculin skin test (TST) using purified protein derivative (PPD), or by Interferon-Gamma-Release Assays (IGRAs) e.g., QuantiFERON® TB Gold Plus (QFT-Plus) or T¬Spot-® (TB Test) within 8 weeks prior to enrollment. Negative results must be complemented by the medical history, physical examination, and Chest X-Ray. Patients presenting positive TST or IGRA, with or without active or clinical suspicion of latent tuberculosis, are not eligible to enter the study.

Previously vaccinated for Tuberculosis patients: IGRA positive patients are not eligible to enter the Study; TST positive patients with an induration of 15 mm and more are also not eligible to enter the study, TST positive patients (with an induration less than 15 mm) are also not eligible to enter the study, unless an IGRA test is subsequently performed and provides a negative result.

Exclusion Criteria:

1. Previous enrollment to this study
2. Participation in another clinical interventional study 30 days prior to enrollment.
3. Treatment with an investigational drug within 5 half-lives prior to enrollment.
4. Previous or current treatment with anakinra, or any other IL-1 inhibitor, except for canakinumab. Previous treatment with canakinumab is allowed if canakinumab was discontinued for reasons other than lack of efficacy and after a washout period of minimum 130 days (Refer to Exclusion Criteria 5). Patients who have discontinued canakinumab because of insufficient effect, refractory disease or toxicities are not allowed to be enrolled in the study.

5. Use of the following therapies prior to enrollment:

   • Narcotic analgesics within 24 hours prior to enrollment.
   • Dapsone within 1 week prior to enrollment or etanercept within 2 weeks prior to enrollment.
   • Intraarticular, intramuscular, or intravenous administration of glucocorticoids within 72h (3 days) prior to enrollment, or intravenous immunoglobulin within 4 weeks prior to enrollment.
   • Leflunomide, infliximab or adalimumab within 8 weeks prior to enrollment.
   • Thalidomide within 72h (3 days) prior to enrollment, cyclosporine within 5 weeks prior to enrollment, tacrolimus hydrate within 2 weeks prior to enrollment, mycophenolate mofetil within 1 week prior to enrollment, 6-mercaptopurine within 48h (2 days) prior to enrollment, azathioprine within 72h (3 days) prior to enrollment, cyclophosphamide within 96h (4 days) prior to enrollment, chlorambucil within 48h (2 days) prior to enrollment, Janus kinase (JAK) inhibitors within 5 half-lives prior to enrollment, or any other immunosuppressant within 12 weeks prior to enrollment.
   • Tocilizumab within 4 weeks prior to enrollment or any other immunomodulatory medication within 5 half-lives prior to enrollment.
   • Rituximab within 26 weeks prior to enrollment.
   • Canakinumab within 130 days prior to enrollment.
6. Live vaccines within 4 weeks prior to enrollment.
7. Known presence or suspicion of active, chronic or recurrent bacterial, fungal or viral infections, including but not limited to tuberculosis, human immunodeficiency virus (HIV) infection, coronavirus disease (Covid-19) infection, hepatitis B or C infection at baseline.

8. Clinical evidence of liver disease or liver injury as indicated by presence of abnormal liver tests:

   1. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) > 5 x upper limit of normal (ULN), or
   2. AST or ALT > 3 x ULN and elevated bilirubin > 2 x ULN.
9. Presence of severe chronic kidney disease (CKD) stages 4 and 5 (estimated creatinine clearance < 30 mL/min/1.73m2).
10. Presence of neutropenia (ANC < 1.5 x 109/L).
11. Presence of thrombocytopenia (platelets count < 100 x 109/L).
12. Presence or suspicion of macrophage activation syndrome (MAS) at baseline.
13. A diagnosis of macrophage activation syndrome (MAS) within the last 2 months prior to enrollment.
14. History of malignancy within 5 years prior to enrollment. Exceptions are basal cell skin cancer, carcinoma-in-situ of the cervix, or low-risk prostate cancer after curative therapy.
15. Known hypersensitivity to E. Coli-derived proteins, or any components of anakinra.
16. Pregnant or lactating women.
17. Foreseeable inability to cooperate with given instructions or study procedures.
18. Presence of any medical, psychological condition, or laboratory result that in the opinion of the investigator can interfere with the patient's ability to comply with the protocol requirements, or make the patient not appropriate for inclusion to the study and treatment with IMP.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Anakinra; Anakinra, once daily s.c. injection, starting dose of 100 mg/day for patients with body weight ≥ 50 kg and 1-2 mg/kg/day for patients with body weight < 50 kg. Pediatric and adult patients weighing ≥ 50kg will receive 100 mg anakinra per day by subcutaneous injection. Pediatric and adult patients weighing < 50 kg should be dosed by body weight with a starting dose of anakinra of 1 to 2 mg/kg/day (with a max of 100 mg/day). If patients receiving 1 mg/kg/d are not responding at Week 1, the dose will be escalated to 2 mg/kg/day. If at the appreciation of the investigator, a patient < 16 years old with a body weight below 50 kg, is not responding sufficiently to anakinra treatment at Week 4 visit, the dose will be adjusted according to actual body weight (rounded to the nearest kg) and will be increased up to 4 mg/kg/day with a max of 200 mg/day or the continuation of anakinra will be considered by the investigator.

Drug: Anakinra (Kineret®); Subcutaneous injections once daily for 48 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ACR30 response at Week 4 with absence of fever attributable to the disease during the 7 days preceding Week 4 visit.	Definition of American College of Rheumatology (ACR) 30 response in SJIA and AOSD patients: An improvement of ≥ 30% from baseline to Week 4 visit, in at least 3 of any 6 variables of the ACR core set listed below, with no more than 1 variable worsening by > 30%. 1. Physician global assessment of disease activity (visual analogue scale [VAS]). 2. Patient/parent global assessment of overall well-being (VAS). 3. Number of joints with active arthritis. 4. Number of joints with limitation of motion. 5. Assessment of physical function (Child health assessment questionnaire [CHAQ]/ Stanford health assessment questionnaire [SHAQ]). 6. CRP (mg/L). Definition of fever: Body temperature ≥ 38.0 °C attributable to the disease. Definition of active arthritis: Joint with swelling. In absence of swelling, limitation of range of motion accompanied by either pain on motion or tenderness not due to deformity.	Up to 48 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Absence of fever during the 7 days preceding week 4.		Up to week 48.
Absence of rash during the 7 days preceding Week 4.		Up to week 48.
ACR50, ACR70, and ACR90 response with absence of fever during the 7 days preceding Week 4.		Up to week 48.
Absence of fever during the 7 days preceding each visit.		Up to week 48.
Absence of rash during the 7 days preceding each visit.		Up to week 48.
ACR30 response with absence of fever during the 7 days preceding each visit.	Definition of ACR30 response in SJIA and AOSD patients: An improvement of ≥ 30%, in at least 3 of any 6 variables of the ACR core set listed below, with no more than 1 variable worsening by > 30%, and no intermittent fever attributable to the disease during the preceding 7 days.	Up to week 48.
ACR50 response with absence of fever during the 7 days preceding each visit.	Definition of ACR50 response in SJIA and AOSD patients: An improvement of ≥ 50%, in at least 3 of any 6 variables of the ACR core set listed below, with no more than 1 variable worsening by > 30%, and no intermittent fever attributable to the disease during the preceding 7 days.	Up to week 48.
ACR70 response with absence of fever during the 7 days preceding each visit.	Definition of ACR70 response in SJIA and AOSD patients: An improvement of ≥ 70% in at least 3 of any 6 variables of the ACR core set listed below, with no more than 1 variable worsening by > 30%, and no intermittent fever attributable to the disease during the preceding 7 days.	Up to week 48.
ACR90 response with absence of fever during the 7 days preceding each visit.	Definition of ACR90 response in SJIA and AOSD patients: An improvement of ≥ 90% in at least 3 of any 6 variables of the ACR core set listed below, with no more than 1 variable worsening by > 30%, and no intermittent fever attributable to the disease during the preceding 7 days.	Up to week 48.
Change from baseline in physician global assessment of disease activity (VAS).		Up to week 48.
Change from baseline in patient/parent global assessment of overall well-being (VAS).		Up to week 48.
Change from baseline in C-reactive protein (CRP) concentrations.	CRP levels (measured in mg/L) will be determined in serum.	Up to week 48.
Change from baseline in ferritin concentrations.	Ferritin levels (measured in ng/ml) will be determined in serum.	Up to week 48.
Change from white blood cell counts.	White blood cell counts (measured in cells per μL) will be determined in serum.	Up to week 48.
Occurrence of inactive disease	Proportion of patients who reach inactive disease at Week 8 and at the following respective visits up to Week 48.	Up to week 48.
Number of Participants with Adverse Events (AEs), Serious Adverse Events (SAEs), deaths, and AEs leading to study drug discontinuation	An AE is any untoward medical occurrence in a study patient to whom a medicinal product is administered, and which does not necessarily have a causal relationship with this treatment. AEs include abnormal test findings, clinically significant signs and symptoms, changes in physical examination findings, progression or worsening of underlying disease. Serious adverse events (SAEs) were defined as any untoward medical occurrences that result in death, are life threatening, require (or prolong) hospitalization, cause persistent or significant disability/incapacity, result in congenital anomalies or birth defects, or are other conditions which in judgement of investigators represent significant hazards.	Up to week 52.
Changes over time in blood pressure	Blood pressure (mmHg) change of each patient are evaluated over time.	Up to week 48.
Changes over time in heart rate	Heart rate (beats per minute) change of each patient are evaluated over time.	Up to week 48.
Changes over time in body temperature	Body temperature (Celsius degrees) change of each patient are evaluated over time.	Up to week 48.
Changes over time in body weight	Body weight (kilograms) for all patients are evaluated over time.	Up to week 48.
Changes over time in height	Height (centimeters) are evaluated over time for pediatric patients	Up to week 48.
Changes over time in Laboratory safety assessment		Up to week 48.
Number of patients with abnormal laboratory values		Up to week 48.
Evaluation of the pharmacokinetic of anakinra in patients with Still's disease.	Anakinra serum concentration at Baseline, Week 2 and Week 4 visits.	Up to 4 weeks

Collaborators and Investigators

• Sponsor: Swedish Orphan Biovitrum
• Collaborators: Tigermed Consulting Co., Ltd

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2025
• Primary Completion (Estimated): September 30, 2028
• Study Completion (Estimated): September 30, 2028

Study Registration Dates

• First Submitted: June 24, 2026
• First Submitted That Met QC Criteria: July 10, 2026
• First Posted (Actual): July 16, 2026

Study Record Updates

• Last Update Posted (Actual): July 16, 2026
• Last Update Submitted That Met QC Criteria: July 10, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Connective Tissue Diseases; Autoimmune Diseases; Immune System Diseases; Arthritis, Rheumatoid; Skin and Connective Tissue Diseases; Arthritis, Juvenile; Still's Disease, Adult-Onset; Peptides; Amino Acids, Peptides, and Proteins; Proteins; Biological Factors; Intercellular Signaling Peptides and Proteins; Cytokines; Interleukin 1 Receptor Antagonist Protein
• Other Study ID Numbers: Sobi.ANAKIN-304

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No