The randomized phase of this study, used for hypotheses testing, enrolled participants from both the United States (US) and EU. An open-label, single-arm extension was available for participants in the EU who completed at least one course of AZLI or TIS during the randomized portion of the study. These participants were eligible to receive 3 additional cycles of AZLI in a 28-day, intermittent, repeating treatment regimen. Results of the extension phase will be available the first quarter (Q1) of 2012.