Abstract
Purpose :
The number of potential eligible subjects for clinical trials (CT) is key for planning the number of investigator sites and duration of a clinical study. The effects of the inclusion and exclusion criteria are difficult to predict and often lead to significantly over optimistic claims by clinicians. For rare chronic conditions, e.g. Stargardt disease (STGD), these errors may lead to early termination and failure of the CT. We utilized a STGD specific database with ≥400 STGD subjects built over 20+ years at the Radboudumc in Nijmegen, and cross-matched clinical features with the inclusion and exclusion criteria for a study to evaluate the safety and efficacy of soraprazan in the treatment of STGD in adult subjects. This was then used to fine tune the inclusion exclusion criteria.
Methods :
A protocol synopsis was carefully designed with involvement of all key investigators, sponsors and other relevant staff. The inclusion criteria narrowed the target population to adults (≥18 years old), with a genetically confirmed, clinical diagnosis of STGD, with an onset before the age of 45 years, BCVA 0.8-0.4, clear media, and with good foveal fixation (EudraCT No. 2018-001496-20, Sponsored by Katairo GmbH, supported by EU program Horizon 2020). Age, BCVA and date of last visit were anticipated to be critical and cross checked to database entries.
Results :
Of the total 406 patients in the database, 238 patients met the age criteria. Patients with a last entry >5 years old were excluded, bringing the number of potential subjects down to 119. Only 13 of these had a BCVA ≥0.4; allowing a BCVA of ≥0.2 and ≥0.1 increased the number of eligible subjects to 23 and 61 respectively. Using this approach, it was possible to review the impact of BCVA on subject availability and adjust the inclusion criteria to ≥0.2 to balance the speed of recruitment rate with the chances of observing a treatment effect.
Conclusions :
Academic centers with an interest in conducting clinical trial research are strongly encouraged to set up patient databases in the diseases of interest. These can be a major planning and efficiency tool for clinical trials in rare conditions. It is important that all relevant consents, in line with national regulation, for the use of such databases is obtained.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.