Last Update: Aug 19, 2026 An Open-label Phase II Trial to Evaluate the Clinical Efficacy, Safety and Tolerability of MAS825 in Pediatric and Adult Participants With Still's Disease ClinicalTrials.gov Identifier: [NCT07203001](https://clinicaltrials.gov/ct2/show/NCT07203001) Novartis Reference Number:CMAS825J12201 [See if you Pre-qualify](#trial-eligibility "See if you Pre-qualify") All compounds are either investigational or being studied for (a) new use(s). Efficacy and safety have not been established. There is no guarantee that they will become commercially available for the use(s) under investigation. ## Study Description The study is a phase II trial designed to evaluate the clinical efficacy, safety, and tolerability of MAS825 (arumakimig) in pediatric and adult participants with Still's disease This is a multicenter, open-label, single-arm study to assess clinical efficacy, safety and tolerability of MAS825 in participants (both pediatric and adult) with Still's disease who have had inadequate response to IL-1 and/or IL-6 or other available therapies. Participants with associated lung disease and/or macrophage activation syndrome may also be included. This study has three periods (Screening, Treatment Period 1, and Treatment Period 2) and a total duration of approximately 16 months. Condition Still´s Disease Phase Phase2 Overall Status Recruiting Number of Participants30 Start Date Nov 03, 2025 Completion Date May 17, 2028 Gender All Age(s) 1 Year - (Child, Adult, Older Adult) ## Interventions Drug ### MAS825 Experimental drug ## Eligibility Criteria Inclusion Criteria: \* Age ≥ 1 with a diagnosis of Still's Disease \* Active diseases defined as: \* CRP or ferritin levels greater than ULN, and any of: \* Fever ≥ 38°C attributed to Still's Disease activity and documented for a number of days prior to Day 1 or \* Rash attributed to Still's Disease activity or \* Musculoskeletal involvement: arthritis in a number of joints per ACP criteria for active joint or \* Serositis or \* Macrophage activation syndrome activity as defined by ferritin levels and at least one of: platelet count, a biomarker or fibrinogen levels attributed to Still's Disease activity by the investigator \* Intolerance or inadequate response to available biologic therapy Exclusion Criteria: \* Patients out of weight range \* Ongoing or previous treatment with immunomodulatory drugs \* A limited number of Still's Disease patients that have previously received MAS825 through a managed access program are permitted on the study \* Glucocorticoid dose exceeding a set limit \* Any conditions or significant medical problems which places the patient at unacceptable risk for MAS825 therapy \* Still's disease patients with evidence of macrophage activation syndrome are permitted in the study \* Still's Disease patients with evidence of interstitial lung disease including those requiring supplemental oxygen therapy are permitted in the study \* History of ongoing, chronic or possibly recurrent infection (e.g. HIV, TB, HCV, HBV) and/or symptoms and signs of clinically significant active bacterial, fungal or viral infections \* Live vaccinations within a set time prior to MAS825 treatment. Live vaccines are prohibited up to several months following the last dose \* History of malignancy of any organ system, including post-transplant lymphoproliferative disorder, treated or untreated, within a number of years, regardless of whether there is evidence of local recurrence and metastases \* History of hypersensitivity to any of the study drugs or to drugs of similar chemical classes or to any of the excipients \* Pregnant or breastfeeding women \* Women of child-bearing potential who do not agree to comply with required contraceptive use Other protocol-defined inclusion/exclusion criteria may apply. France #### Novartis Investigative Site Recruiting Bron,69677,France #### Novartis Investigative Site Recruiting Le Kremlin-Bicêtre,94275,France #### Novartis Investigative Site Recruiting Lille,59037,France #### Novartis Investigative Site Recruiting Paris,75015,France #### Novartis Investigative Site Recruiting Paris,75970,France #### Novartis Investigative Site Recruiting Bordeaux,33076,France Germany #### Novartis Investigative Site Recruiting Heidelberg,69120,Germany #### Novartis Investigative Site Recruiting Münster,48149,Germany #### Novartis Investigative Site Recruiting Sankt Augustin,North Rhine-Westphalia,53757,Germany Italy #### Novartis Investigative Site Recruiting Florence,FI,50139,Italy #### Novartis Investigative Site Recruiting Roma,RM,00165,Italy #### Novartis Investigative Site Recruiting Genova,GE,16147,Italy Spain #### Novartis Investigative Site Recruiting Madrid,28046,Spain #### Novartis Investigative Site Recruiting Esplugues,Barcelona,08950,Spain #### Novartis Investigative Site Recruiting Valencia,46026,Spain Turkey (Türkiye) #### Novartis Investigative Site Recruiting Istanbul,Fatih,34098,Turkey (Türkiye) #### Novartis Investigative Site Recruiting Ankara,Sihhiye-Altindag,06230,Turkey (Türkiye) United States #### University of Utah Recruiting Salt Lake City,Utah,84113,United States ###### Tressie Rollins Phone: [+1 415 515 8212]() Email: ###### Aimee Ogden Hersh #### Legacy Emanuel Research Hosp Portland Recruiting Portland,Oregon,97232,United States ###### Daniel Joseph Kingsbury ###### Brenna Bogle Phone: [+1 503 413 5447]() Email: ## Worldwide Contacts If the location of your choosing does not feature any contact detail, please reach out using the information below. #### Novartis Pharmaceuticals Phone: [ +41613241111](tel:+41613241111) Email: [](mailto:) #### Novartis Pharmaceuticals Phone: [ 1-888-669-6682](tel:1-888-669-6682) Email: