The new chief executive of Credit Suisse’s investment bank has made a series of dramatic changes to its top ranks, as the Swiss bank attempts to return the loss-making division to profit.

David Miller, who succeeded Jim Amine as chief executive of Credit Suisse’s investment banking and capital markets division in November, has installed new leadership and shaken up the structure of the division, according to memos seen by Financial News and confirmed by a spokeswoman from the bank.