Theodor studied statistics at the Dortmund University of Technology and at the University of Auckland. He joined the Institute of Biostatistics at Hannover Medical School in 2009 where his main areas of work were consulting, teaching and clinical trials. He also served as a deputy member for the Ethics Committee at Hannover Medical School and completed a PhD in Biostatistics. Theodor works as a Seconded National Expert at the EMA since September 2020.