Translation as a medium of cultural communication and transformation in late antiquity and the Middle Ages is at the center of Dr Vagelpohl's research. Translations from Greek into Arabic had an immeasurable impact on all aspects of medieval and modern Islamic civilization; they are emblematic for the wide-ranging cultural and scientific exchanges between East and West in the early Middle Ages. Apart from the linguistic issues involved, Dr Vagelpohl is also keenly interested in the complex interactions between Muslim scholars and their religious beliefs and the antique philosophical and scientific heritage throughout the Middle Ages.

At Warwick, he contributed from 2008 to 2012 to the Warwick Epidemics, the edition of the Arabic version of the first two books of Galen's Commentary on the Hippocratic Epidemics funded by the Wellcome Trust and supervised by Simon Swain and Peter E Pormann. In fall 2012, he started his own Wellcome Fellowship project, an edition and translation of Book 6 of the same commentary.