Abstracts

Rationale: The assessment of efficacy in an adult focal epilepsy clinical trial using an electronic seizure diary (eDiary) instead of a paper diary is being explored, following on from the successful use of an eDiary in pediatric epilepsy clinical trials. We sought to determine the compliance with the eDiary in the X-TOLE adult focal onset epilepsy study.

Methods: The eDiary compliance was assessed by evaluation of the database for the proportion of eDiary days completed per study phase. Central surveillance of eDiary functionality and compliance was utilized to inform participating sites of their subjects’ status, in order to enable them to provide encouragement in real time. Seizure counts could only be entered in the eDiary on the day after their occurrence until up to 3 retrospective days.

Results: The median (range) duration of the Baseline period was 57.5 (53-139) days for the first 300 subjects randomized in the study (age range:18-74 yeas). During Baseline, eDiary compliance was 95.6 ± 6.7% (mean ± SD) and median compliance was 98.4% for these 300 subjects. A minimum of 80% eDiary compliance was required for randomization and 15 subjects failed Baseline for this reason. A further 71 subjects were not randomized, due to recording less than the protocol-specified minimum of 4 seizures/month, or >21 consecutive days without a seizure during Baseline. At the time of writing, for the 235 subjects that had completed the 56 day randomized treatment period, eDiary compliance during the randomization period was maintained at 94.8 ± 8.4% (mean ± SD) and median compliance was 98.2%.

An unexpected opportunity to explore the flexibility and utility of an eDiary was presented by the occurrence of the global COVID pandemic. The eDiary had a capability of capturing 200 days. Therefore, when in-person visits needed to be delayed due to COVID, as per protocol amendment, the subjects were permitted to continue in Baseline up to a maximum of 140 days until the required in-person randomization visit could take place. The seizure requirement (≥4 seizures per month) to be randomized was assessed over the first 56 days and it was determined whether the baseline could continue, if an in-person visit could not be performed. Thirty-two subjects thus had an extended Baseline period of 67-139 days.

Conclusions: We learned that eDiary compliance could be maintained very highly in adult focal epilepsy subjects, aided by central monitoring in real time. Further, in the face of unforeseen circumstances, the eDiary helped to maintain a strong connection to the subject’s clinical status to enable eventual progression through the study with accurate information.

Funding: Please list any funding that was received in support of this abstract.: This research was funded by Xenon Pharmaceuticals Inc.