Efficacy Study of Targeted, Local Delivery of Drugs to Treat Crohn's Disease

Overview

The study is being undertaken to evaluate whether delayed-release medications, designed to begin to open in the lower intestinal tract, the main site of Crohn's Disease, are more effective than standard systemically delivered drugs to promote remission or response in CD patients. It is hypothesized that the delayed-release medications will go right to the injured tissue and heal the disease more quickly. The delayed-release test drugs are 6-mercaptopurine (at a dose of 40 mg daily) or calcitriol (at a dose of 5 mcg three times a week) versus Purinethol (6-MP at a dose of 1-2 mg/kg body weight daily). Calcitriol is a synthetically manufactured replica of a natural substance in the body that is derived from Vitamin D. There is much medical evidence that shows that lack of Vitamin D can be a possible risk factor in developing autoimmune disorders, including Crohn's Disease. Moreover, calcitriol has been shown in animal models to improve the symptoms of Crohn's Disease.

This pilot clinical study is designed to evaluate the efficacy and safety of oral administration of novel, delayed-release test formulations, for targeted delivery to the ileum in Crohn's Disease patients. The local delivery drugs (delayed-release formulations of 6-mercaptopurine or calcitriol) will be compared to standard Purinethol treatment after 12 weeks of treatment to evaluate: * (1) local intestinal mucosal inflammation and damage as shown by markers of biopsy tissue (CDEIS and pathologist review of biopsies); * (2) Clinical symptoms of active Crohn's Disease \[CDAI scores- remission \<150; response- a drop of 100 points from baseline; IBDQ scores- \>= 180 indicative of remission\]; and * (3)Systemic improvement as shown by blood immunological and inflammatory markers (CRP and ESR). It is hypothesized that since CD is a localized autoimmune inflammation of the intestinal mucosa, a far more effective, and potentially safer treatment would be targeted, local delivery of effective drugs directly to the disease site. The drug would be concentrated in the specific area of disease, while unwanted systemic side effects would be minimized. The drugs selected for evaluation are 6-MP (a mainstay of CD treatment for over 30 years) and calcitriol, a synthetically manufactured Vitamin D derivative, which is being evaluated in many studies for its impressive immunomodulatory effects in cancer, MS and other autoimmune disorders.