As is often the case, the major challenge was in recruiting a sufficient number of patients. In this study, the challenge was exacerbated by an aggressive timeline, the need to include only IBS patients who were not experiencing constipation, and the existence of competing non-constipation IBS studies.

Quintiles was able to anticipate recruiting challenges and was prepared, meeting recruitment goals in only 10 months, well ahead of the anticipated 15. Subsequently, database lock was completed early, allowing an earlier submission of the NDA.