Statistical analysis
SECONDARY
A sample size of 150 patients for PRIME and PRIME2 each was estimated to provide 90% power to detect a 28% difference in the primary endpoint between dupilumab and placebo with a Fisher exact test at a two-sided alpha of 0.05, assuming response rates of 39% and 11%, respectively. Efficacy analyses were performed in the intention-to-treat population, which included all randomized patients analyzed according to the intervention group allocated by randomization regardless of whether the treatment kit was used or not. Safety analyses were performed on all patients randomly assigned to study intervention and who received at least one dose of study intervention. Patients were analyzed according to the intervention they received.A study-level multiplicity procedure was used to control for the overall type I error rate for testing primary, key secondary and selected other endpoints (Extended Data Table 