Safety and Immunogenicity of the Live Attenuated Tetravalent Butantan-Dengue Vaccine in Autoimmune Rheumatic Diseases

Inclusion Criteria: * Age between 12 and 59 years * Male or female * Clinical diagnosis of an autoimmune rheumatic disease (ARD) based on internationally accepted criteria (e.g., rheumatoid arthritis, systemic lupus erythematosus, juvenile idiopathic arthritis, Sjögren's syndrome, vasculitis) * Healthy control matched by age and sex * ARD patients with clinically stable disease for at least 3 months * ARD patients under low-grade immunosuppression or no immunosuppression * Acceptable immunosuppressive treatments include: Hydroxychloroquine Sulfasalazine Prednisone ≤ 20 mg/day Methotrexate ≤ 0.4 mg/kg/week (maximum 20 mg/week) Leflunomide 20 mg/day Azathioprine \< 3 mg/kg/day Combination therapy with low-dose prednisone (≤ 7.5 mg/day), hydroxychloroquine, or sulfasalazine * Healthy controls with no history of autoimmune or chronic infectious diseases * Healthy controls not taking immunosuppressive medications Willing and able to comply with study procedures and follow-up * Female participants of reproductive potential with negative pregnancy test at baseline * Female participants of reproductive potential agreeing to use effective contraception for at least 90 days after vaccination Exclusion Criteria: * Prior receipt of any dengue vaccine * Receipt of a live attenuated vaccine within 4 weeks prior to enrollment * Receipt of an inactivated vaccine within 2 weeks prior to enrollment * Known allergy to any component of the vaccine * Febrile illness (≥ 37.8°C) within 72 hours prior to vaccination * History of immunodeficiency syndromes * History of asplenia * History of cancer * History of HIV infection * History of primary immunodeficiencies * Immunosuppression due to organ transplant * Chronic uncontrolled comorbidities (e.g., heart failure, renal failure, hepatic insufficiency, diabetes mellitus) * Hospitalization or acute illness at screening * Receipt of blood transfusion within 3 months prior to enrollment * Current pregnancy or breastfeeding * Intention to become pregnant within 90 days post-vaccination * Participation in another clinical trial within 30 days prior to enrollment