Dr Middelburg obtained his Bachelor's degree in Chemistry at Nijmegen University (the Netherlands). In 2015, he continued with the research Master Drug Innovation in Utrecht, switching towards the biological side of science. During his internships, he studied the prevention of cow's milk allergy by encapsulating tolerogenic peptides in nanoparticles (Utrecht Institute of Pharmaceutical Sciences, the Netherlands), the role of the protein DKK2 in melanoma using mouse models (the Netherlands Cancer Institute) and the development of a rhesus macaque bispecific neutralizing antibody against HIV (the Scripps Research Institute, USA).

After obtaining his Master's degree in 2018, he started his PhD at the department of Medical Oncology at the Leiden University Medical Center under supervision of Professor Dr Thorbald van Hall and Professor Dr Sjoerd van der Burg. During his doctoral work, he mainly focused on improving the efficacy of CD3 bispecific antibody therapy in solid cancers through therapeutic vaccination approaches in collaboration with biotech company Genmab, resulting in multiple first-author publications (Cancer Cell, Nature Communications, JITC) and a patent (WO2022/049220 A2 entitled Antibody Therapy). Additionally, he conducted more fundamental research involving the immune checkpoint ligand Qa-1b, resulting in a first-author publication in Cell Reports.

He then joined the lab of Associate Professor Paul Beavis in the department of Cancer Immunology at Peter MacCallum Cancer Centre in 2024 as a postdoctoral researcher. His current interests involve improving CAR T cell therapy in both solid and haematological malignancies through genetic (CRISPR/Cas9) engineering to improve the persistence and function of CAR T cells, which are both known to be major obstacles for therapeutic efficacy.