The invention relates to a combination comprising an antineoplastic agent, e.g. an antimetabolite antineoplastic agent and a type 1 serotonin receptor (HTR1) modulator, e.g. a HTR1 antagonist. In addition the invention relates to a pharmaceutical composition comprising a combination of the invention and a pharmaceutically acceptable excipient. The invention also relates to the combination and pharmaceutical composition according to the invention for use in medicine, particularly for use in the prevention and/or treatment of a hematological malignancy.