Post hoc Analysis of the Relationship Between Plasma Citrulline and Parenteral Support Needs in Patients With Short Bowel Syndrome With Intestinal Failure Receiving Teduglutide: 1185

Introduction: Plasma citrulline has been proposed as a biomarker for remnant intestinal length, but it is unclear whether plasma citrulline levels reflect intestinal absorptive function. This post hoc analysis investigated the relationship between reductions in parenteral support (PS) volume and changes in plasma citrulline levels with teduglutide (TED) in patients with intestinal failure associated with short bowel syndrome (SBS-IF). Methods: STEPS (NCT00798967; EudraCT 2008-006193-15) was a 24-week, placebo-controlled study of TED 0.05 mg/kg/day in patients with SBS-IF. Plasma citrulline levels were assessed at baseline and Week 24 in all patients randomized to TED and in patients stratified by bowel anatomy. Results: In the TED arm (n=42), plasma citrulline levels at baseline were significantly correlated with remnant small bowel length (R2=0.14; P=0.02; n=36) but not with baseline PS volume (R2=0.03; P=0.30; n=39). The correlation between baseline plasma citrulline and plasma citrulline change at Week 24 was significant (R2=0.80; P< 0.0001; n=39). No correlation was found between change in plasma citrulline levels and change in PS volume at Week 24 with TED (R2=0.05; P=0.16; n=39). When patients were analyzed by bowel anatomy subgroups, significant increases in plasma citrulline were seen with TED but not placebo (Table).Table: Table. Mean (SD) Change From Baseline at Week 24 in PS Volume and Plasma Citrulline, Stratified by Bowel AnatomyConclusion: Plasma citrulline may serve as a marker of remnant small bowel length in patients with SBS-IF, but plasma citrulline does not predict PS volume reductions with TED. Plasma citrulline changes with TED may reflect increased enterocyte mass.