Pilot/Ph I Safety and Efficacy of ODSH in Protein Losing Enteropathy Secondary to Single Ventricle Palliative Surgery

Protein Losing Enteropathy (PLE)is a serious and sometimes fatal condition that develops in approximately 10% of children who have undergone the single ventricle palliative surgery known as the Fontan procedure. The mechanisms by which PLE develops are not fully understood, however a recent mechanism has been proposed consistent with the specific loss of heparan sulfate proteoglycans from the basolateral surface of the intestinal epithelial cells resulting in the loss of serum protein including albumin and immunoglobulins into the gastrointestinal tract that is associated with protein losing enteropathy. A number of clinical studies have suggested that heparin administration can have clinical benefit in children with PLE, however the risk of bleeding as a consequence of treatment is an important concern and commonly limits its administration. ODSH (2-0, 3-0 desulfated heparin) is a modified heparin that preserves the anti-inflammatory properties of heparin with minimal or no anticoagulation effects. ODSH has been studied in the rodent model of PLE an has shown improvement of PLE in this model due to restoration of heparan sulfate and Syndecan 1 with stabilization of the cell matrix of the capillary endothelium. This open label clinical study will enroll 9 subjects with a dose escalation (3 doses) study design. Three subjects will be treated with the lower dose of ODSH then an ad hoc safety committee will assess the safety information to make a recommendation regarding advancing to the next higher dose of ODSH until, if appropriate, the 3 dose cohorts have been completed. Plasma albumin and fecal alpha 1 antitrypsin which are both biological markers of protein loss through the intestinal lumen in this condition, are the primary variables that will be evaluated as evidence of a therapeutic effect together with the improvement of PLE signs and symptoms. The effect of ODSH on the associated diarrhea, abdominal pain, and peripheral edema or ascites will be evaluated using visual/categorical scales for the patients to assess symptoms and clinical evaluation by the investigator.