The Dutch company ENPICOM has developed a novel platform to capture and monitor a patient's immune response from a simple blood sample or biopsies. This platform uses advanced bioinformatics algorithms to generate a so-called 'immune fingerprint', based on the RNA sequences in the immune cells of the patient's blood or tissues. Among others, ENPICOM?s platform is capable of real-time monitoring the dynamics of an adaptive immune response, based on e.g. clonal expansion and contraction. In the current Eurotstars project this method will be applied to patient samples from an Ultimovacs' clinical trial investigating the therapeutic cancer vaccine UV1 in patients with advanced melanoma with the aim to demonstrate the utility of this method in characterizing the patients immune response following vaccination for analysis of efficacy and biomarker development