Table 1.

Calculated sample size requirements

Parameters	Double-blinda	Open-label extensionb
A1P mean (SE)	−1.45 (0.23)	−1.45 (0.23)
Placebo mean (SE)	−2.19 (0.25)	−1.74 (0.25)
Difference	0.74	0.29
Common SD	2.25	2.25
Effect size	0.32	0.13
N per group	147	946

SE standard error, SD standard deviation, N number of patients

^aAnnual rate of lung density change from baseline to 24 months (A1PI versus placebo)

^bAnnual rate of lung density change from baseline to 24 months (A1PI versus delayed-start A1PI)