Statistical Methods: All statistical tests related to treatment effect were 2-sided, and statistical significance was declared at the 0.05 probability level. Least squares means (LSMeans) were used to estimate treatment effect. Populations analyzed included the Full Analysis (intent-to-treat [ITT]) Set (FAS), Per-Protocol Set (PPS), Safety-Analyzable Set, and All-Screened Analysis Set. Demographic and baseline data for all subjects in the Safety-Analyzable Set were summarized and listed. The effects of treatment at the Overall and all other analysis Time Points were assessed using ANCOVA models. The main effects model contained terms for treatment and Investigator site, with baseline TSSC value as a covariate. The LSMeans and standard errors were based on the main effects model. Methods of analysis of secondary efficacy data included analysis of covariance (ANCOVA) models and Cochran-Mantel-Haenszel (CMH) row mean scores tests. Analysis of drug safety included the incidence of treatment-emergent AEs (TEAE), concomitant medications, vital signs, and physical examination findings for the Safety-Analyzable Set.