Mario D. Saltarelli

A double-blind, randomized, placebo-controlled trial of divalproex extended-release in the treatment of bipolar disorder in children and adolescents.

OBJECTIVE To compare the efficacy and safety of divalproex extended-release (ER) to placebo in a 28-day double-blind study of bipolar disorder in children and adolescents and evaluate the safety of divalproex ER in a 6-month open-label extension study. METHOD In the double-blind study, 150 patients (manic or mixed episode, aged 10-17 years) with baseline Young Mania Rating Scale (YMRS) score of 20 or higher were randomized to once-daily placebo or divalproex ER, which was titrated to clinical response or serum valproate concentration of 80 to 125 microg/mL. Sixty-six patients enrolled in the extension study. RESULTS In the double-blind study, a treatment effect was not observed with divalproex ER based on change in mean YMRS score (divalproex ER -8.8 [n = 74]; placebo -7.9 [n = 70]) or secondary measures. Divalproex was similar to placebo based on incidence of adverse events. Four subjects treated with divalproex ER and three treated with placebo discontinued because of adverse events. Mean ammonia levels increased in the divalproex ER group, but only one patient was symptomatic. In the long-term study, YMRS scores decreased modestly (2.2 points from baseline). The most common adverse events were headache and vomiting. CONCLUSIONS The results of the study do not provide support for the use of divalproex ER in the treatment of youths with bipolar I disorder, mixed or manic state. Further controlled trials are required to confirm or refute the findings from this study.

Blockade of [11C](+)-PHNO binding in human subjects by the dopamine D3 receptor antagonist ABT-925

Dopamine D3 receptors are preferentially localized in the limbic system and midbrain, and thus may be involved in the pathophysiology of neuropsychiatry disorders. [11C](+)-PHNO is the first preferential D3 receptor radioligand in humans, yet there are no blockade studies with a D3 receptor antagonist in humans. This study characterized the blockade of [11C](+)-PHNO binding by ABT-925, a D3 receptor antagonist, in healthy male subjects. Sixteen subjects underwent 2-3 positron emission tomography (PET) scans, at baseline and following one or two doses of ABT-925 ranging from 50 mg to 600 mg. Receptor occupancies were estimated for globus pallidus, substantia nigra, caudate, putamen, and ventral striatum. At the 600-mg dose (n=9), ABT-925 receptor occupancy (mean+/-s.d.) was higher in substantia nigra (75+/-10%) and globus pallidus (64+/-22%) than in ventral striatum (44+/-17%), caudate (40+/-18%) and putamen (38+/-17%) (ANOVA: F4,140=15.02, p<0.001). The fractions of [11C](+)-PHNO binding attributable to D3 receptors in D3 receptor-rich regions were 100% (substantia nigra) and 90% (globus pallidus), and in D2 receptor-rich regions were 55% (caudate) and 53% (putamen). The ED50 of ABT-925 was 4.37 microg/ml across regions. Our results demonstrate that [11C](+)-PHNO binding can be blocked by a D3 receptor antagonist and confirm preclinical findings that [11C](+)-PHNO signal in the substantia nigra and globus pallidus is mainly reflective of its binding to D3 receptors. Thus, [11C](+)-PHNO seems a suitable PET radiotracer to estimate D3 receptor occupancy in humans.

Divalproex ER Combined with Olanzapine or Risperidone for Treatment of Acute Exacerbations of Schizophrenia

The objective of this study was to evaluate the efficacy and safety of divalproex sodium extended release (divalproex ER) vs placebo in combination with olanzapine or risperidone for the treatment of acute exacerbations of schizophrenia. In this 12-week, randomized, double-blind, parallel-group, multi-center trial, a total of 402 patients were randomized and treated; 103 received olanzapine/placebo, 99 received olanzapine/divalproex ER, 101 received risperidone/placebo, and 99 received risperidone/divalproex ER. Divalproex ER was initiated on day 1 at 20 mg/kg per day q AM and was titrated to clinical effect on days 3, 7, and 10, not to exceed a maximum dosage of 35 mg/kg per day. Olanzapine and risperidone were initiated at 5 and 2 mg/day q PM, respectively, increased to 10 and 4 mg/day on day 3, and increased to fixed target doses of 15 and 6 mg/day on day 6. No significant treatment difference was demonstrated between the combination therapy and antipsychotic monotherapy groups on the primary efficacy variable of the mean change from baseline to day 14 last observation carried forward on the Positive and Negative Syndrome Scale (PANSS) total score, although antipsychotic monotherapy did demonstrate superiority to combination therapy on the PANSS Negative subscale at several time points. Combination therapy also failed to show an advantage over antipsychotic monotherapy at day 84 on the PANSS total score. Most adverse events observed in the study were mild to moderate in severity, and the overall number of adverse events did not differ significantly between the combination therapy groups and their corresponding antipsychotic monotherapy group.

Suicidality and divalproex sodium: analysis of controlled studies in multiple indications

BackgroundRecent analyses of antiepileptic drugs have indicated an increase in the risk of suicidality. The objective of this report was to provide clinical information and an independent meta-analysis of divalproex sodium and suicidality events by analyzing data from 13 placebo-controlled studies and 1 low-dose controlled study.MethodsAdverse events considered to be possibly suicide related were identified using the Columbia Classification Algorithm of Suicide Assessment (C-CASA) methodology. Indications included epilepsy, bipolar disorder, migraine prophylaxis, impulsive aggression, and dementia. Narratives were produced for every event, and suicidality event ratings were performed by a third party blinded to treatment assignment. Statistical analyses were conducted using methodology similar to that reported by the US Food and Drug Administration (FDA).ResultsSuicidality events were identified in 5 of the 13 placebo-controlled studies. Of the 1,327 (0.83%) subjects taking divalproex sodium, 11 had suicidality events: 2 suicide attempts and 9 suicidal ideation. Of 992 (0.91%) subjects taking placebo, 9 had suicidality events: 1 preparatory act toward suicide, 2 suicide attempts, and 6 suicidal ideation. Across placebo-controlled studies, the overall estimated odds ratio (OR) of suicidal behavior or ideation was 0.72 (95% CI 0.29 to 1.84). The OR for suicidal behavior was 0.37 (95% CI 0.04 to 2.58), and the OR for suicidal ideation was 0.90 (95% CI 0.31 to 2.79).ConclusionsIn this meta-analysis, divalproex sodium does not appear to increase the risk of suicide-related adverse events relative to placebo in the populations studied. Clinicians should nonetheless remain vigilant in assessing suicidality, not only in patients treated for mental disorders with inherently high suicide risk, but also in patients taking antiepileptic medications.

Divalproex Extended-Release in Adolescent Migraine Prophylaxis: Results of a Randomized, Double-Blind, Placebo-Controlled Study

Objective.— To evaluate the efficacy, tolerability, and safety of 3 different doses of divalproex sodium extended‐release vs placebo in the prophylaxis of migraine headaches in adolescents.

Safety and Efficacy of ABT-089 in Pediatric Attention-Deficit/Hyperactivity Disorder: Results from Two Randomized Placebo-Controlled Clinical Trials.

OBJECTIVE To assess the safety and efficacy of ABT-089, a novel α(4)β(2) neuronal nicotinic receptor partial agonist, vs. placebo in children with attention-deficit/hyperactivity disorder (ADHD). METHOD Two multicenter, randomized, double-blind, placebo-controlled, parallel-group studies of children 6 through 12 years of age were conducted. Study 1 (n = 274) assessed six treatment groups over 8 weeks: 4 once-daily (QD) ABT-089 doses (0.085-0.700 mg/kg), QD atomoxetine, and placebo. Study 2 (n = 119) assessed three treatment groups over 6 weeks: 2 QD ABT-089 doses (0.7 mg/kg, 1.4 mg/kg) and placebo. The primary efficacy variable was the investigator-administered Attention-Deficit/Hyperactivity Disorder Rating Scale-IV: Home Version (ADHD-RS-IV [HV]) Total Score. Safety was assessed by adverse event (AE) monitoring, laboratory tests, vital signs, physical examinations, and electrocardiogram measures. RESULTS There was no statistically significant difference between ABT-089 and placebo in mean change from baseline to final evaluation of ADHD-RS-IV (HV) Total Score or other outcome measures at any dose in either study. In Study 1, atomoxetine showed statistically significant improvement for the primary and most secondary endpoints. ABT-089 was generally safe and well tolerated, with no statistically significant difference between any ABT-089 dose and placebo in the overall incidence of any specific AE, and no clinically significant changes in other safety measures. CONCLUSIONS ABT-089 did not show efficacy on the primary efficacy variable, the ADHD-RS-IV (HV) Total Score, or other measures of ADHD symptomatology in children with ADHD, and had a safety profile similar to placebo. These results contrast with published reports of efficacy of nicotinic modulators in adults with ADHD.

A Double-Blind, Randomized, Placebo-Controlled Study of the Dopamine D3 Receptor Antagonist ABT-925 in Patients With Acute Schizophrenia

There is substantial preclinical and clinical evidence to suggest a potential role for the dopamine D3 receptor in the treatment of schizophrenia. ABT-925 is a selective dopamine D3 receptor antagonist with an approximately 100-fold higher in vitro affinity for dopamine D3 versus D2 receptors. This double-blind, randomized, placebo-controlled, escalating-dose, parallel-group study assessed the efficacy and safety of ABT-925 in the treatment of patients with acute exacerbation of schizophrenia. One hundred fifty-five patients were assessed over a 6-week double-blind treatment period (placebo: n = 48; ABT-925 50 mg once daily [QD]: n = 53; ABT-925 150 mg QD: n = 54). The primary efficacy measure was mean change from baseline to final evaluation on the Positive and Negative Syndrome Scale total score. Secondary measures of efficacy and pharmacokinetic parameters were also assessed. Safety assessments included adverse event monitoring, laboratory tests, vital signs, movement rating scales, and electrocardiogram measures. No statistically significant treatment effect was observed with ABT-925 50 mg QD or 150 mg QD compared with placebo on primary or secondary efficacy end points. Pharmacokinetic parameter estimates increased with dose in a linear fashion. ABT-925 50 mg QD and 150 mg QD were generally well tolerated, with adverse event profiles similar to that of placebo. Findings from a concurrent positron emission tomography study among healthy volunteers suggest that the ABT-925 doses used in this study may not have been sufficient to adequately occupy D3 receptors, thereby underscoring the importance of pharmacodynamic markers, such as PET, in determining appropriate compound doses before embarking on studies in a target population.

Divalproex Sodium Extended‐Release for the Prophylaxis of Migraine Headache in Adolescents: Results of a Stand‐Alone, Long‐Term Open‐Label Safety Study

Objective.— The objective of this long‐term open‐label study in adolescents was to assess the safety and tolerability of divalproex sodium extended‐release in the prophylaxis of migraine headaches.

Long-term safety of divalproex sodium extended-release in children and adolescents with bipolar I disorder.

OBJECTIVE The objective of this open-label study was to assess the safety of divalproex sodium extended-release in the treatment of children and adolescents with acute mania associated with bipolar I disorder. METHODS This was a 6-month, Phase 3, open-label study in healthy subjects aged 9-17 years with a current Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition, Text Revision (DSM-IV-TR) diagnosis of bipolar I disorder manic or mixed episode. Divalproex sodium extended-release (DVPX-ER) was initiated at 15 mg/kg per day on day 1 (not to exceed 750 mg/day) with increases allowed to a maximum of 35 mg/kg per day. Study visits were conducted on day 1 and at months 1, 2, 3, and 6. Assessments included standard safety evaluations and appropriate rating scales for clinical effect. RESULTS A total of 226 subjects were enrolled; 109 subjects completed the study. The most common adverse events were weight gain (16%), nausea (9%), and increased appetite (8%). Nonsymptomatic elevations of mean ammonia levels in plasma were observed. The mean Young Mania Rating Scale (YMRS) decreased 12.4 from baseline to final visit; small improvements were seen in behavior and caregiver stress ratings. CONCLUSIONS DVPX-ER was generally well tolerated in children and adolescents with acute mania, with a side-effect profile similar to that observed in adults.

Safety and Tolerability of Divalproex Sodium Extended‐Release in the Prophylaxis of Migraine Headaches: Results of an Open‐Label Extension Trial in Adolescents

Objective.— To evaluate the long‐term safety and tolerability of divalproex sodium extended‐release in the prophylaxis of migraine headaches in adolescents.