Pgi23 Identifying Endpoints for Irritable Bowel Syndrome (Ibs) Clinical Trials: Incorporating the Patient's Voice

Psychometric validation of symptom severity measures in irritable bowel syndrome with constipation

“…The results of the present psychometric evaluation are consistent with the results of similar psychometric analyses conducted with phase 2b linaclotide trial data and build on the qualitative evidence for the IBS‐C Symptom Severity Measures demonstrating that these measures have satisfactory psychometric properties and are reliable, valid and responsive in an IBS‐C population. Ensuring the measures used to derive trial endpoints have acceptable psychometric properties supports the conclusion of a treatment benefit for linaclotide in the primary bowel symptom and abdominal symptom endpoints and all key secondary endpoints in the clinical studies.…”

“…Ensuring the measures used to derive trial endpoints have acceptable psychometric properties supports the conclusion of a treatment benefit for linaclotide in the primary bowel symptom and abdominal symptom endpoints and all key secondary endpoints in the clinical studies. While the full set of IBS‐C symptoms addressed by the IBS‐C Symptom Severity Measures has been identified as important to patients through extensive qualitative research and content validation, currently only two symptoms – abdominal pain and BM frequency – are recommended by the FDA to define primary endpoints in IBS‐C trials to support drug approval . However, because the FDA has indicated a preference for the development and use of a multi‐item PRO instrument to capture all clinically important symptoms of IBS‐C within the primary endpoint of future trials, the factor analyses explored the feasibility of one or more multi‐item IBS‐C composites.…”

“…Reliable and valid patient‐reported outcome (PRO) measures are needed to directly assess patient's response to therapy. Based on a synthesis of relevant literature and patient interviews, and in accordance with recommendations set forth in the Food and Drug Administration's (FDA's) guidance, Patient‐Reported Outcome ( PRO ) Measures: Use in Medical Product Development to Support Labeling Claims , a novel set of patient‐reported IBS‐C Symptom Severity Measures was developed to assess abdominal and bowel symptoms within the linaclotide clinical development programme . Based on these PRO symptom measures, primary and secondary endpoints were developed for a phase 2b study and two phase 3 trials investigating the efficacy and safety of linaclotide, a minimally absorbed peptide agonist of the intestinal guanylate cyclase type‐C receptor, in patients with IBS‐C …”