Pivotal Study Design
From pilot study data, the evaluable pivotal study cohort was expected to demonstrate difference between Intergel and control group mean mAFS = 4.1: second look mean mAFS score adjusted for baseline.
Assumptions:
Loss to follow-up: 20% Intergel group; 10% control group
Loss to follow-up patients assigned mAFS score = 16 in Intent to Treat Analysis (ITT).
Clinically significant difference between Intergel and control group mean mAFS = 4.1 => 2.1 with adjustment for expected loss to follow - up (ITT).
Sample size, n = 180, to detect a difference of 2.1 in mean mAFS score, standard deviation = 5.0 for both groups, assuming ITT analysis.
Power = 80%; Significance level = 0.05.