Significant efficacy in reducing ADHD symptoms

The data demonstrated that INTUNIV showed significant efficacy in reducing ADHD symptoms for patients taking the medication when compared to patients taking placebo at all measured time points up to 24 hours postdose.

The U.S. Food and Drug Administration (FDA) issued an approvable letter on June 20, 2007, regarding INTUNIV. Shire is conducting additional clinical work which is designed to enhance the label. Upon approval, INTUNIV will be the first selective alpha-2A receptor agonist indicated for the treatment of ADHD that may provide an important treatment option for patients and physicians.

Summary of Analyses

The pooled analysis evaluated results from these patients on a weight adjusted mg/kg basis from two similarly designed, randomized, double-blind, forced-dose titration, multicenter phase III trials. The primary efficacy measure for both studies was change in the ADHD Rating Scale (ADHD-RS-IV) total score from baseline to endpoint. All patient groups treated with INTUNIV showed significantly greater improvement in ADHD-RS-IV total score from baseline to endpoint than the placebo group (P < .001). The ADHD-RS-IV is a standardized, validated test for assessing symptoms of ADHD and for assessing their response to treatment.

The analysis also studied duration of effect using the Conners' Parent Rating Scale-Revised Short Form (CPRS-R), which is a comprehensive scale that used observer and self-report ratings to help assess ADHD and evaluate behavioral issues in children and adolescents. The CPRS-R assessments were completed on specified days at approximately 6 PM (after school and before dinner), 8 PM (dinner through bedtime) and 6 AM (waking time/new dose administration time), which represented 12, 14 and 24 hours after the administration of the dose of INTUNIV, respectively. The data demonstrated significant improvement of ADHD symptoms based on total endpoint CPRS-R scores for all weight adjusted dose groups treated with INTUNIV when compared to placebo for all time periods (at 12 hours, P < = .001; at 14 hours, P < .001; and at 24 hours, P=.003).

A separate analysis of the same phase III studies evaluated the percentage of ADHD patients who responded to weight-adjusted treatment with INTUNIV versus those participants receiving placebo. Using the change in the ADHD-RS-IV total score from baseline to endpoint as the primary efficacy measure, responders were defined as those with a 25 percent reduction in score from baseline to endpoint. Findings from the analysis showed that all groups treated with INTUNIV responded to the medication in a shorter time period than the placebo group (14 days versus 20 days, respectively, P = .001).

In the phase III studies, adverse events (AEs) were reported in 80.7 percent of patients treated with INTUNIV and 71.8 percent of patients treated with placebo. Overall, the AEs were mostly mild to moderate in severity. Adverse reactions that appeared to be dose-related in patients given INTUNIV included upper abdominal pain, constipation, dizziness, dry mouth, hypotension, sedation, and somnolence. Serious AEs reported in these analyses were uncommon and rates were similar between patients treated with INTUNIV and patients treated with placebo (0.6% of the INTUNIV group and 0.7% of placebo group, respectively). -Porter Novelli