Marc Jansen

Marc Jansen, MD, PhD, is a pediatric immunologist-rheumatologist at UMC Utrecht with a research focus on immune-mediated inflammatory diseases in children. He obtained his PhD in pediatric neuro-oncology, contributing to clinical trial development, imaging studies, and predictive modeling.

In his current clinical practice, Dr. Jansen treats children with systemic autoimmune diseases and neuro(muscular) inflammatory disorders. These chronic conditions often require long-term immunosuppressive therapy, exposing patients to the detrimental effects of persistent inflammation and significant treatment-related toxicity, particularly associated with glucocorticosteroid use.

Dr. Jansen’s research centers on juvenile dermatomyositis (JDM), aiming to develop more effective and safer targeted therapies through biomarker-based decision-making. To elucidate disease mechanisms, he collaborates closely with the Center for Translational Immunology (CTI). In parallel, he conducts therapeutic drug monitoring (TDM) studies in collaboration with the Department of Pharmacy, focusing on the relationship between prednisolone plasma concentrations and glucocorticoid toxicity.

In addition, Dr. Jansen investigates the impact of immunosuppressive and immunomodulatory therapies on vaccine responses in pediatric patients. He chaired the task force that developed the EULAR/PRES European Recommendations on vaccination in children with rheumatic diseases and has led and participated in multiple clinical trials, including studies on anti-TNF therapy and MenACWY vaccination in collaboration with the Dutch National Institute for Public Health and the Environment (RIVM), as well as trials evaluating the safety and immunogenicity of MMR booster and COVID-19 vaccines in immunocompromised children.

Dr. Jansen is actively involved in education and supervision, serving as a supervisor for medical trainees and fellows in pediatric immunology and rheumatology, and contributing to the training of the next generation of clinician-scientists.