2A3 mAb (Northwestern University)

Crohn's disease is an autoimmune disorder that affects nearly 1.4 million Americans. The etiology of Crohn's disease is not completely understood, however, research has suggested a genetic link. There is currently no known cure for Crohn's disease and, as a result, most government-funded research is being conducted to increase the quality of life of afflicted patients (i.e. reducing chronic inflammation and alleviating growth impairment in pediatric patients). A number of treatment options are available including an alpha-4 integrin inhibitor and several TNF-alpha inhibitors. Furthermore, research is being conducted on several alternative treatment options to help understand exactly which cellular mechanisms (i.e. inducing apoptosis in leukocytes) are required for clinical efficacy. This review seeks to chronicle the current available treatment options for patients affected by Crohn's disease to aid in understanding potential cellular mechanistic requirements for an efficacious drug, and shed light on potential options for future treatment.

The number of anti-inflammatory and immunomodulatory drugs being developed in the pharmaceutical industry has increased considerably in the past decade. This increase in research and development has been paralleled by questions from both regulatory agencies and industry on how best to assess decreased host resistance to infections or adverse immunostimulation caused by immunomodulatory agents such as anti-cytokine antibodies (e.g., the tumor necrosis factor-alpha inhibitors), anti-adhesion molecule antibodies (e.g., anti-alpha-4 integrin inhibitors) and immunostimulatory molecules (e.g., anti-CD28 antibodies). Although several methods have been developed for nonclinical assessment of immunotoxicity, highly publicized adverse events have brought to light significant gaps in the application of nonclinical immunotoxicity testing in assessing potential risk in humans. Confounding this problem is inconsistent application of immunotoxicology methods for risk assessment within the scientific community, limited understanding of appropriate immunotoxicity testing strategy for immunomodulators and inconsistent testing requests by regulatory agencies. To address these concerns, The Immunotoxicology Technical Committee (ITC) of the International Life Science Institute (ILSI) Health and Environmental Sciences Institute (HESI) organized a workshop on Immunomodulators and Clinical Immunotoxicology in May 2007. The Workshop was convened to identify key gaps in nonclinical and clinical immunotoxicity testing of anti-inflammatory and immunomodulatory agents and to begin to develop consistent approaches for immunotoxicity testing and risk assessment. This paper summarizes the outcome of the HESI ITC Immunomodulators and Clinical Immunotoxicology Workshop. Topics not discussed at the Workshop were outside the scope of this report. Although more work is needed to develop consistent approaches for immunotoxicity assessment of immunomodulators, this Workshop provided the foundation for future discussion.