According to the Centers for Disease Control (CDC), data suggest that the number of people worldwide who suffer from ulcerative colitis (UC) — a chronic and serious disease of the colon — varies greatly, from 0.1 person per 100,000 to 16 people per 100,000. The illness is most prevalent in Europe and North America and less common in developing Asian countries.
Most UC patients respond extremely well to systemic steroids and are able to avoid colectomy. A smaller percentage of people, however, suffer from steroid refractory ulcerative colitis — failure to respond to corticosteroids — and need alternative treatment options.
The primary challenge was in recruiting a sufficient number of patients as the potential study population of true steroid refractory patients was quite small. Numerous patients thought to be steroid refractory actually responded to corticosteroids during screening and could not be included. Many sites were reluctant to put patients on 40-50 mg of corticosteroids as per protocol. Finally, the existence of several competing large global studies further reduced the pool of potential patients and interested sites.
In addition, the Mayo score (or Disease Activity Index [DAI] used to define and measure disease activity) depended heavily on the somewhat subjective sub-scores assigned from endoscopy findings and physicians' global assessment. As a result, patient scores were neither standardized nor objective.
In order to address the known recruitment challenges, Quintiles used aggressive startup and pre-screening activities and was exceptionally diligent in site selection. The only sites targeted were those that could prove their ability to enroll by providing historical data from other UC trials and that were not involved in a competing trial.