Mean change from baseline on the semiquantitative scale (SQS) for mycobacterial culture growth through the end of the open-label phase (missing value equals failure; modified intent-to-treat population). The SQS is a mycobacterial culture reporting method expressed on a seven-step scale that uses outcomes ranging from no growth at 6 weeks (step 1), growth in liquid media only (step 2), agar positive (1–49 colonies) (step 3), 1+ (step 4), 2+ (step 5), 3+ (step 6), and 4+ (step 7). Change from baseline ranges from +6 (worsening) to −6 (improvement) steps. Death, regardless of cause, was considered a failure and is represented by a +7-step worsening. *All patients in the open-label phase received liposomal amikacin for inhalation (LAI). PBO = placebo.