Dresdner Kleinwort Wasserstein has promoted Arndt Muthreich, its global head of investment grade credit research, to run its overall credit research business following the resignation of Lior Jassur, who was head of high-yield debt coverage.

Jassur, who joined Wasserstein Perella, the US boutique, in late 1999 and has been part of the research team at DrKW since the German bank bought Wasserstein Perella for $1.4bn (€1.2bn) in January 2001, is understood to have moved to a non-research role at a rival bank.