The immunogenicity of anti-tumor necrosis factor alpha (anti-TNF) therapy in inflammatory bowel disease (IBD) is an important cause of loss of response to therapy that may lead to escalation of dose or discontinuation of therapy. Antibodies may develop to infliximab (ATI) or to adalimumab (ATA) and cause this loss of response, also known as a secondary loss of response. An alternative approach is the addition of immunomodulator (IM) therapy to counteract the antibody response and regain efficacy of the biologic medication. The investigators' goal is to treat patients' who have lost response to adalimumab or infliximab with an immunomodulator with the goal of eliminating the circulating antibodies to the anti-TNF and restoring efficacy.