In many immune-mediated diseases such as Crohn’s disease and rheumatoid arthritis the immune system requires suppression. This is where biological therapy comes in, such as the administration of therapeutic antibodies targeting inflammatory proteins or blocking the activity/trafficking of immune cells. However, treatment success is variable and there are no biomarkers capable of predicting clinical response, causing unnecessary suffering to patients and high healthcare costs. The EU-funded METHYLOMIC project focuses on epigenetics as a means of predicting the outcome of biological therapies. Researchers will introduce and validate DNA methylation biomarkers as accurate predictors of response to therapy.