There is provided a compound of formula I or a pharmacologically acceptable salt thereof for use in a method of treating Hodgkin lymphoma in a patient in need thereof comprising administering to said patient an effective amount of said compound of formula I or a pharmacologically acceptable salt thereof: a combination of said compound of formula I or a pharmaceutically acceptable salt thereof with Brentuximab Vedotin and said combination for use in a method of treating Hodgkin lymphoma in a patient in need thereof comprising administering to said patient an effective amount of said combination.