Predicting non-responsiveness of ibd patients

An in vitro diagnostic method for predicting the responsiveness of an IBD (Irritable Bowel Disease) patient to a therapy with an intracellularly acting immunosuppressive agent of interest, said method comprising the steps of

• providing a sample of said IBD patient from a biological sample taken from said IBD patient at a time before treatment with the intracellularly acting immunosuppressive agent of interest or up to the 4th month of treatment with the immunosuppressive agent of interest,
• said sample comprising effector mononuclear cells,
• obtaining a transporter activity level by measuring transport activity by a multidrug ABC transporter, in the effector mononuclear cells in said sample, and
• comparing the transporter activity level with a reference transporter activity level,
• said reference transporter activity value being determined in a group of patients, which serve as a reference, i.e. for comparison by
• providing biological samples of said group of patients, said sample comprising effector mononuclear cells from said patient, and
• obtaining one or more transporter activity value(s) by measuring transport activity by one or more multidrug ABC transporter(s) selected from the group consisting of B, C and G class, in the effector mononuclear cells in said sample, wherein said transporter is the same as the transporter the activity is measured in the method of the invention,
• considering said patient as a non-responder to the therapy with the intracellularly acting immunosuppressive agent of interest when the transporter activity level is significantly different from the respective reference transporter activity level
• wherein the intracellularly acting immunosuppressive agent is different from a steroid when the multidrug ABC transporter(s) is MDR1.