Shire Plc (SHPG) shares are up sharply in trading today after the company announced top-line results from a Phase 3 clinical trial, study 306 evaluating its investigational SHP465 for the treatment of symptoms of attention-deficit/ hyperactivity disorder (ADHD) in adults showed a significant treatment benefit compared to placebo. Specifically, SHP465 was superior to placebo as measured by the change from baseline to week 4 in a rating scale called ADHD-RS. It was also superior to placebo on a key secondary endpoint measured by the clinical global impression improvement scale (CGI-I) at week 4.