A phase 2 autologous cellular therapy trial in patients with acute, complete spinal cord injury: pragmatics, recruitment, and demographics
Study design:Post hoc analysis from a randomized controlled cellular therapy trial in acute, complete spinal cord injury (SCI).Objectives:Description and quantitative review of study logistics, referral patterns, current practice patterns and subject demographics.Setting:Subjects were recruited to one of six international study centers.Methods:Data are presented from 1816 patients pre-screened, 75 participants screened and 50 randomized.Results:Of the 1816 patients pre-screened, 53.7% did not meet initial study criteria, primarily due to an injury outside the time window (14 days) or failure to meet neurological criteria (complete SCI between C5 motor/C4 sensory and T11). MRIs were obtained on 339 patients; 51.0% were ineligible based on imaging criteria. Of the 75 participants enrolled, 25 failed screening (SF), leaving 50 randomized. The primary reason for SF was based on the neurological exam (51.9%), followed by failure to meet MRI criteria (22.2%). Of the 50 randomized subjects, there were no significant differences in demographics in the active versus control arms. In those participants for whom data was available, 93.8% (45 of 48) of randomized participants received steroids before study entry, whereas 94.0% (47 of 50) had spine surgery before study enrollment.Conclusion:The ‘funnel effect’ (large numbers of potentially eligible participants with a small number enrolled) impacts all trials, but was particularly challenging in this trial due to eligibility criteria and logistics. Data collected may provide information on current practice patterns and the issues encountered and addressed may facilitate design of future trials.