Study Data Show INTUNIV™ (guanfacine) Extended Release Tablets Co-administered With Stimulants Provided ADHD Symptom Improvement in Children and Adolescents

NEW ORLEANS, May 21 /PRNewswire-FirstCall/ -- Shire plc (LSE: SHP, Nasdaq: SHPGY), the global specialty biopharmaceutical company, today announced new findings on once-daily INTUNIV™ (guanfacine) Extended Release Tablets, the first selective alpha-2A agonist approved for the treatment of Attention Deficit Hyperactivity Disorder (ADHD), at a major psychiatric meeting.  The primary objective of this study was to evaluate the efficacy of INTUNIV, dosed either in the morning or evening compared with placebo, when co-administered with stimulant medications used to treat ADHD in children and adolescents ages 6 to 17 with ADHD and suboptimal response to stimulant alone.  The study met its primary end point, which was the change from baseline to end point in the ADHD Rating Scale-IV (ADHD RS-IV) total score.

"A considerable number of pediatric patients with ADHD experience a suboptimal response to stimulant treatment for their ADHD.  Finding the right treatment while managing medication side effects may be complicated," said Timothy Wilens, M.D., staff in the pediatric psychopharmacology unit at Massachusetts General Hospital and associate professor of psychiatry at Harvard Medical School, who led the study.  "We hope that these new data from a large multisite controlled study evaluating the efficacy and safety of extended-release guanfacine co-administered with stimulants for the treatment of ADHD in children and adolescents will be helpful to clinicians in the management of their patients with ADHD."

The US Food and Drug Administration (FDA) approved INTUNIV on September 2, 2009 as an ADHD treatment for children and adolescents ages 6 to 17, based on two pivotal monotherapy studies.  These data presented today were included as part of a supplemental New Drug Application (sNDA) submitted to the FDA on April 28, 2010 to seek approval for INTUNIV as adjunctive treatment with long-acting oral stimulants for the treatment of ADHD in this patient population.  

In the pivotal trials, INTUNIV alone provided significant efficacy across a range of ADHD symptoms that can be disruptive, such as inattentiveness/being easily distracted, impulsivity/interrupting others, hyperactivity/running around excessively, arguing with adults, and losing temper.  INTUNIV is a non-scheduled medication and has no known potential for abuse or dependence.   INTUNIV is available in US pharmacies in four dosage strengths:  1 milligram (mg), 2 mg, 3 mg, and 4 mg.  

INTUNIV Co-Administered With a Stimulant Demonstrated Significant Symptom Improvement vs. Stimulant Alone

This 9-week, randomized, double-blind, placebo-controlled, parallel-group, dose-optimized phase III study enrolled patients aged 6 to 17 years with a diagnosis of ADHD and suboptimal response* to treatment with a long-acting stimulant.

Throughout the study, patients continued to take their same once-daily dose of a long-acting stimulant and were randomized to three treatment arms:  INTUNIV dosed in the morning, INTUNIV dosed in the evening, or placebo.  A total of 455 patients were evaluated for efficacy and safety.  The study consisted of 5 weeks of dose optimization and 3 weeks of dose maintenance.  INTUNIV was optimized up to 4 mg per day.  

The primary efficacy analysis was the change from baseline in ADHD-RS-IV total score at end point.  ADHD-RS-IV is a standardized test for evaluating symptoms of ADHD and assessing response to treatment.   At baseline, mean ADHD-RS-IV total scores were 37.6, 37.0, and 37.7 for the INTUNIV AM/stimulant, INTUNIV PM/stimulant, and placebo/stimulant treatment groups, respectively.  At study end, mean ADHD-RS-IV total scores were 17.3, 16.1, and 21.7, respectively.  Placebo-adjusted least squares (LS) mean change from baseline at end point for ADHD-RS-IV total score was a decrease of 4.5 (P=.002) for the INTUNIV AM/stimulant and a decrease of 5.3 (P<.001) for the INTUNIV PM/stimulant.

In this study, no unique adverse events were observed with INTUNIV given with stimulant compared with those reported with either treatment alone.  The most commonly reported treatment emergent adverse events (TEAEs) among patients treated with INTUNIV and a stimulant (greater than or equal to 5 percent) were headache, somnolence, upper respiratory tract infection, fatigue, insomnia, upper abdominal pain, dizziness, decreased appetite, cough, irritability, and nausea.  The most commonly reported TEAEs among patients in the placebo/stimulant group were headache, upper respiratory tract infection, and irritability.  The majority of TEAEs were mild to moderate in severity.   The rate of discontinuation due to TEAEs was 2.7 percent in the INTUNIV AM/stimulant group, 3.9 percent in the INTUNIV PM/stimulant group, and 0.7 percent in the placebo/stimulant group.  There were three serious adverse events reported among study participants (including one report of syncope) and all were considered unrelated to study drug.  No deaths occurred during the study.

"Shire is committed to ADHD and continues to develop a range of ADHD treatments for health care providers and patients," said Michael Yasick, Senior Vice President of Shire's ADHD Business Unit.  "We are pleased with the results of this trial and are currently working with the FDA to secure an indication for use of INTUNIV with stimulants in the treatment of ADHD."  

This study was supported by funding from Shire Development Inc.  Dr Timothy Wilens was a speaker and received grant support from and is a consultant for Shire.  

*Suboptimal response was defined as treatment with a stable dose of stimulant for at least four weeks with improvement, yet persistence of mild to moderate ADHD symptoms (defined as an ADHD-RS-IV total score of at least 24 and Clinical Global Impressions-Severity of illness scale score of at least three).

About INTUNIV

Once-daily INTUNIV is the first non-scheduled selective alpha-2A agonist for the treatment of ADHD in children and adolescents aged 6 to 17.  INTUNIV was approved in the United States in September 2009 and is available in US pharmacies in four dosage strengths of 1 mg, 2 mg, 3 mg, and 4 mg.  INTUNIV is not a controlled substance and has no known potential for abuse or dependence.

Although it is not known exactly how INTUNIV works, guanfacine, the active ingredient in INTUNIV, has been shown to interact with certain receptors in the part of the brain called the prefrontal cortex (PFC).   Research has shown that behaviors related to ADHD, such as inattention and impulsiveness, may be controlled in this part of the brain.

Additional information about INTUNIV and Full Prescribing Information are available at www.intunivpro.com.

Indication and Important Safety Information

INTUNIV is indicated for the treatment of Attention Deficit Hyperactivity Disorder (ADHD) in children and adolescents ages 6 to 17.  Efficacy was established in two controlled clinical trials (8 and 9 weeks in duration).  The physician electing to use INTUNIV for extended periods should periodically reevaluate its long-term usefulness for the individual patient.

INTUNIV is indicated as an integral part of a total treatment program for ADHD that may include other measures (psychological, educational, and social).

INTUNIV should not be used in patients with a history of hypersensitivity to guanfacine or any of its inactive ingredients or by patients taking other products containing guanfacine.

Hypotension, bradycardia, and syncope were observed in clinical trials.  Use INTUNIV with caution in treating patients who have experienced hypotension, bradycardia, heart block, or syncope, or who may have a condition that predisposes them to syncope; are treated concomitantly with antihypertensives or other drugs that can reduce blood pressure or heart rate or increase the risk of syncope.  Heart rate and blood pressure should be measured prior to initiation of therapy, following dose increases, and periodically while on therapy.  Advise patients to avoid becoming dehydrated or overheated.

Sedation and somnolence were commonly observed in clinical trials.  The potential for additive sedative effects with CNS depressant drugs should be considered.  Patients should be cautioned against operating heavy equipment or driving until they know how they respond to INTUNIV.  Advise patients to avoid use with alcohol.

Common adverse reactions in patients taking INTUNIV that may be dose related over the range of 1 to 4 mg/day include somnolence, sedation, abdominal pain, dizziness, hypotension/decreased blood pressure, dry mouth, and constipation.

Please see accompanying Full Prescribing Information at http://www.intuniv.com/documents/INTUNIV_Full_Prescribing_Information.pdf  

About ADHD

ADHD is one of the most common psychiatric disorders in children and adolescents.  Worldwide prevalence of ADHD is estimated at 5.3 percent (with large variability), according to a comprehensive systematic review of this topic published in 2007 in the American Journal of Psychiatry.  In the United States, approximately 7.8 percent of all school-aged children, or about 4.4 million children aged 4 to 17 years, have been diagnosed with ADHD at some point in their lives, according to the Centers for Disease Control and Prevention (CDC).

ADHD is a psychiatric behavioral disorder that manifests as a persistent pattern of inattention and/or hyperactivity-impulsivity that is more frequent and severe than is typically observed in individuals at a comparable level of development.  The specific etiology of ADHD is unknown and there is no single diagnostic test for this disorder.  Adequate diagnosis requires the use of medical and special psychological, educational and social resources, utilizing diagnostic criteria such as Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV®) or International Classification of Diseases 10 (ICD-10).

Although there is no cure for ADHD, there are accepted treatments that specifically target its symptoms.  Standard treatments include educational approaches, psychological or behavioral modification, and/or medication.

SHIRE PLC

Shire's strategic goal is to become the leading specialty biopharmaceutical company that focuses on meeting the needs of the specialist physician. Shire focuses its business on attention deficit hyperactivity disorder (ADHD), human genetic therapies (HGT) and gastrointestinal (GI) diseases as well as opportunities in other therapeutic areas to the extent they arise through acquisitions. Shire's in-licensing, merger and acquisition efforts are focused on products in specialist markets with strong intellectual property protection and global rights. Shire believes that a carefully selected and balanced portfolio of products with strategically aligned and relatively small-scale sales forces will deliver strong results.

For further information on Shire, please visit the Company's website: www.shire.com.

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Statements included herein that are not historical facts are forward-looking statements. Such forward-looking statements involve a number of risks and uncertainties and are subject to change at any time. In the event such risks or uncertainties materialize, the Company's results could be materially adversely affected. The risks and uncertainties include, but are not limited to, risks associated with: the inherent uncertainty of research, development, approval, reimbursement, manufacturing and commercialization of the Company's Specialty Pharmaceutical and Human Genetic Therapies products, as well as the ability to secure and integrate new products for commercialization and/or development; government regulation of the Company's products; the Company's ability to manufacture its products in sufficient quantities to meet demand; the impact of competitive therapies on the Company's products; the Company's ability to register, maintain and enforce patents and other intellectual property rights relating to its products; the Company's ability to obtain and maintain government and other third-party reimbursement for its products; and other risks and uncertainties detailed from time to time in the Company's filings with the Securities and Exchange Commission.

SOURCE Shire plc