Yangchun Du

Evaluation of Opioid Modulation in Major Depressive Disorder

Although opioids have known antidepressant activity, their use in major depressive disorder (MDD) has been greatly limited by risk of abuse and addiction. Our aim was to determine whether opioid modulation achieved through a combination of a μ-opioid partial agonist, buprenorphine (BUP), and a potent μ-opioid antagonist, samidorphan (SAM), would demonstrate antidepressant activity without addictive potential. A placebo-controlled crossover study assessed the opioid pharmacodynamic profile following escalating doses of SAM co-administered with BUP in opioid-experienced adults. A subsequent 1-week, placebo-controlled, parallel-group study was conducted in subjects with MDD and an inadequate response to standard antidepressant therapy. This second study evaluated safety and efficacy of ratios of BUP/SAM that were associated with partial and with maximal blockade of opioid responses in the initial study. Pupillometry, visual analog scale assessments, and self-reported questionnaires demonstrated that increasing amounts of SAM added to a fixed dose of BUP resulted in dose-dependent reductions in objective and subjective opioid effects, including euphoria and drug liking, in opioid-experienced adults. Following 7 days of treatment in subjects with MDD, a 1 : 1 ratio of BUP and SAM, the ratio associated with maximal antagonism of opioid effects, exhibited statistically significant improvement vs placebo in HAM-D17 total score (p=0.032) and nearly significant improvement in Montgomery-Åsberg Depression Rating Scale (MADRS) total score (p=0.054). Overall, BUP/SAM therapy was well tolerated. A combination of BUP and SAM showed antidepressant activity in subjects with MDD. Balanced agonist–antagonist opioid modulation represents a novel and potentially clinically important approach to the treatment of MDD and other psychiatric disorders.

Opioid Modulation With Buprenorphine/Samidorphan as Adjunctive Treatment for Inadequate Response to Antidepressants: A Randomized Double-Blind Placebo-Controlled Trial

OBJECTIVE Major depressive disorder has been associated with dysregulation of the endogenous opioid system. The authors sought to determine whether opioid modulation achieved through administration of ALKS 5461, a combination of a μ- and κ-opioid partial agonist, buprenorphine, and a μ-opioid antagonist, samidorphan, would exhibit antidepressant activity in patients with major depression. METHOD A multicenter, randomized, double-blind, placebo-controlled, two-stage sequential parallel comparison design study was conducted in adults with major depression who had an inadequate response to one or two courses of antidepressant treatment. Participants were randomly assigned to receive adjunctive treatment with 2 mg/2 mg of buprenorphine/samidorphan (the 2/2 dosage group), 8 mg/8 mg of buprenorphine/samidorphan (the 8/8 dosage group), or placebo. Antidepressant effect was measured based on change from baseline to the end of 4 weeks of treatment on the 17-item Hamilton Depression Rating Scale (HAM-D), the Montgomery-Åsberg Depression Rating Scale (MADRS), and the Clinical Global Impressions severity scale (CGI-S). RESULTS Compared with the placebo group, there were significantly greater improvements in the 2/2 dosage group across the three depression outcome measures (HAM-D: -2.8, 95% CI=-5.1, -0.6; MADRS: -4.9, 95% CI=-8.2, -1.6; CGI-S: -0.5, 95% CI=-0.9, -0.1). There was also evidence of improvement in the 8/8 dosage group, although it did not achieve statistical significance. Overall, the buprenorphine/samidorphan combinations were well tolerated, and there was no evidence of opioid withdrawal on treatment discontinuation. CONCLUSIONS The buprenorphine/samidorphan combination is a novel and promising candidate for treatment of major depressive disorder in patients who have an inadequate response to standard antidepressants.

A Randomized, Double-Blind, Placebo-Controlled Trial of Aripiprazole Lauroxil in Acute Exacerbation of Schizophrenia

OBJECTIVE This study evaluated the efficacy, safety, and tolerability of aripiprazole lauroxil, a novel long-acting injectable atypical antipsychotic, for the treatment of schizophrenia. METHOD An international multicenter, randomized, double-blind, placebo-controlled trial was conducted between December 2011 and March 2014. Patients (N = 623) aged 18 to 70 years with schizophrenia (DSM-IV-TR criteria), experiencing an acute exacerbation, were randomized in a 1:1:1 ratio to receive gluteal intramuscular injection of aripiprazole lauroxil 441 mg, aripiprazole lauroxil 882 mg, or matching placebo once monthly for 12 weeks. The primary efficacy outcome was change in Positive and Negative Syndrome Scale (PANSS) total score from baseline to day 85. The Clinical Global Impressions-Improvement scale (CGI-I) score at day 85 was the secondary efficacy outcome. Safety and tolerability were assessed. RESULTS The PANSS total score (mean ± standard error [SE]) improved significantly from baseline to day 85 in the aripiprazole lauroxil 441 mg and 882 mg groups, with placebo-adjusted differences of -10.9 ± 1.8 (P < .001) and -11.9 ± 1.8 (P < .001), respectively. Significant (P ≤ .004) improvements in both active treatment groups were demonstrated as early as day 8 and continued throughout the treatment period. The proportion of patients who were very much or much improved on the CGI-I was significantly greater with aripiprazole lauroxil 441 mg and 882 mg treatment versus placebo (P < .001). The most common treatment-emergent adverse events were insomnia, akathisia, headache, and anxiety. The incidence of injection site reactions was low, predominantly described as injection site pain, and was associated with the first injection. CONCLUSIONS Aripiprazole lauroxil demonstrated robust efficacy for treatment of patients experiencing acute exacerbation of schizophrenia. The improvement in psychotic symptoms was statistically significant and clinically meaningful. Symptom improvement occurred rapidly after initiation of aripiprazole lauroxil treatment and was maintained throughout the study. Both aripiprazole lauroxil 441 mg and 882 mg doses were well tolerated. These results support aripiprazole lauroxil as an important new treatment option for schizophrenia. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01469039; Clinicaltrialsregister.eu identifier: 2012-003445-15.

Relative bioavailability and safety of aripiprazole lauroxil, a novel once-monthly, long-acting injectable atypical antipsychotic, following deltoid and gluteal administration in adult subjects with schizophrenia.

Aripiprazole lauroxil is a linker lipid ester of aripiprazole for extended-release intramuscular (IM) injection. This multicenter, randomized, open-label study evaluated the pharmacokinetics (PK), relative bioavailability, and tolerability of a single IM deltoid or gluteal injection of aripiprazole lauroxil in adult subjects with chronic stable schizophrenia or schizoaffective disorder. Forty-six subjects were randomized 1:1 to aripiprazole lauroxil 441 mg IM in the deltoid or gluteal muscle. Samples were collected through 89 days post-dose to measure levels of aripiprazole lauroxil, N-hydroxymethyl aripiprazole, aripiprazole, and dehydro-aripiprazole. Forty-three (93.5%) subjects completed all study assessments; most were CYP2D6 extensive or immediate metabolizers (96%); two (4%) were poor metabolizers. The PK of aripiprazole following aripiprazole lauroxil was characterized by a steady rise in plasma concentrations (Tmax 44-50 days), a broad peak, and prolonged exposure attributable to the dissolution of aripiprazole lauroxil and formation rate-limited elimination of aripiprazole (t1/2=15.4-19.2 days). Deltoid vs. gluteal administration resulted in slightly higher Cmax aripiprazole concentrations [1.31 (1.02, 1.67); GMR 90% CI]; total exposure (AUCinf) was similar between sites of administration [0.84 (0.57, 1.24)]. N-hydroxymethyl-aripiprazole and dehydro-aripiprazole exposures were 10% and 33-36%, respectively, of aripiprazole exposure following aripiprazole lauroxil. The most common adverse events were injection site pain in 20 subjects (43.5%) and headache in 6 subjects (13.0%) of mild intensity occurring at a similar rate with deltoid and gluteal administration. Exposure ranges with deltoid and gluteal administration overlapped, suggesting that these sites may be used interchangeably. Despite a higher incidence of adverse events, deltoid muscle provides a more accessible injection site and could facilitate patient acceptance.

Effect of Aripiprazole Lauroxil on Metabolic and Endocrine Profiles and Related Safety Considerations Among Patients With Acute Schizophrenia.

OBJECTIVE Aripiprazole lauroxil, a long-acting injectable antipsychotic, demonstrated safety and efficacy in treating symptoms of schizophrenia in a double-blind, placebo-controlled trial. Because the metabolic profile of antipsychotics is an important safety feature, the effects of aripiprazole lauroxil on body weight, endocrine and metabolic profiles, and safety were examined in a secondary analysis. METHODS Patients with schizophrenia (DSM-IV-TR criteria) were randomly assigned to aripiprazole lauroxil 441 mg, aripiprazole lauroxil 882 mg, or placebo intramuscularly once monthly between December 2011 and March 2014. Changes in body weight, body mass index, fasting blood glucose and serum lipids, glycosylated hemoglobin (HbA1c), and prolactin over 12 weeks were assessed. The incidence of treatment-emergent adverse events (AEs) was evaluated. RESULTS Among 622 randomized patients, no clinically relevant changes from baseline to week 12 were observed for any serum lipid, lipoprotein, plasma glucose, or HbA1c value with placebo or either dose of aripiprazole lauroxil. Both doses of aripiprazole lauroxil were associated with reductions in mean prolactin levels, whereas placebo treatment was not. The mean (standard deviation) change from baseline for body weight was 0.74 (3.9) kg, 0.86 (3.7) kg, and 0.01 (3.6) kg for aripiprazole lauroxil 441 mg, aripiprazole lauroxil 882 mg, and placebo groups, respectively. AEs related to metabolic parameters were reported in 2.4%, 1.4%, and 2.4% of patients in the aripiprazole lauroxil 441 mg, aripiprazole lauroxil 882 mg, and placebo groups, respectively. CONCLUSIONS Aripiprazole lauroxil was well tolerated, with a low-risk metabolic profile relative to published data for other antipsychotics. Changes similar to those observed with placebo were observed in the aripiprazole lauroxil groups for metabolic parameters, with modest weight gain in the active treatment groups over the 12-week course. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01469039.

Efficacy and safety of aripiprazole lauroxil in schizophrenic patients presenting with severe psychotic symptoms during an acute exacerbation

Aripiprazole lauroxil (AL), a new long-acting injectable antipsychotic, demonstrated safety and efficacy in treating acute exacerbation symptoms of schizophrenia in a 12-week placebo-controlled trial of two doses of AL (441mg and 882mg) administered every 4weeks. We performed a post hoc analysis of this trial to evaluate the efficacy of AL in the subgroup of patients with severe psychotic symptoms, defined as those with baseline Positive and Negative Syndrome Scale (PANSS) Total score above the median score of 92 (n=309). Change from baseline to Day 85 in PANSS Total score; Positive, Negative, and General Psychopathology subscale scores; and overall response rate were assessed. Statistically significant and clinically meaningful improvements in PANSS Total score were demonstrated with AL 441mg and AL 882mg, with placebo-adjusted differences of -14.7 (p<0.0001) and -16.6 (p<0.0001), respectively. Significant and clinically meaningful findings with both doses of AL were also demonstrated for the PANSS subscales and responder rates. Overall responder rates at Day 85 were significantly greater for AL 441mg (49%; p<0.001) and 882 mg (61%; p<0.001) groups vs. placebo (18%). Common adverse events (>5%) were schizophrenia, akathisia, headache, insomnia, and anxiety. AL demonstrated robust efficacy in treatment of the subgroup of patients experiencing severe psychotic symptoms. Both doses (441mg and 882mg) were effective, with numerically greater improvement in symptoms and proportion of responders favoring the higher dose arm. Both doses had a side effect profile consistent with the known safety profile of aripiprazole.

Effect of aripiprazole lauroxil on agitation and hostility in patients with schizophrenia.

This study aimed to evaluate the effects of aripiprazole lauroxil on hostility and aggressive behavior in patients with schizophrenia. Patients aged 18–70 years with a diagnosis of schizophrenia and currently experiencing an acute exacerbation or relapse were randomized to intramuscular (IM) aripiprazole lauroxil 441 mg (n=207), 882 mg (n=208), or placebo (n=207) for 12 weeks. In post-hoc analyses, hostility and aggression were assessed by the Positive and Negative Syndrome Scale (PANSS) Hostility item (P7) and a specific antihostility effect was assessed by adjusting for positive symptoms of schizophrenia, somnolence, and akathisia. The PANSS excited component score [P4 (Excitement), P7 (Hostility), G4 (Tension), G8 (Uncooperativeness), and G14 (Poor impulse control)], and the Personal and Social Performance scale disturbing and aggressive behavior domain were also assessed. Of the 147 patients who received aripiprazole lauroxil 882 mg and with a baseline PANSS Hostility item P7 more than 1, there was a significant (P<0.05) improvement versus placebo on the PANSS Hostility item P7 score by mixed-model repeated-measures at the end of the study, which remained significant when PANSS-positive symptoms and somnolence or akathisia were included as additional covariates. The proportion with PANSS Hostility item P7 more than 1 at endpoint was significantly (P<0.05) lower with aripiprazole lauroxil versus placebo (53.6, 46.1, and 66.3% for 441, 882 mg, and placebo). A significant (P<0.05) improvement was found with aripiprazole lauroxil versus placebo for change from baseline in the PANSS excited component score. The proportion of patients with aggressive behavior on the Personal and Social Performance scale was significantly (P<0.05) lower for aripiprazole lauroxil: 30.0% for 441 mg versus 44.1% for placebo (P=0.006) and 22.2% for 881 mg (P<0.001 versus placebo). Treatment with aripiprazole lauroxil resulted in decreases in agitation and hostility in patients with schizophrenia and this antihostility effect appears to be independent of a general antipsychotic effect.

Durability of therapeutic response with long-term aripiprazole lauroxil treatment following successful resolution of an acute episode of Schizophrenia

OBJECTIVE To evaluate durability of therapeutic effect of long-term treatment with aripiprazole lauroxil in patients with schizophrenia following successful treatment of an acute psychotic episode. METHODS This post hoc analysis assessed long-term outcomes for a subgroup of patients who entered a 52-week extension study after being successfully stabilized with one of 2 doses of aripiprazole lauroxil (441 or 882 mg) in a pivotal 12-week, placebo-controlled, randomized clinical trial. Durability of therapeutic effect was measured by the proportion of patients completing the 1-year course of aripiprazole lauroxil, the trajectories of the Positive and Negative Syndrome Scale (PANSS) total and the Clinical Global Impression-Severity (CGI-S) item scores beyond the first 12 weeks, and the likelihood of remission at any follow-up point. RESULTS In total, 181 patients treated with aripiprazole lauroxil entered the extension study; 73% and 66% of patients from the 441 mg and 882 mg groups, respectively, completed all 13 aripiprazole lauroxil treatments scheduled every 4 weeks over 52 weeks. Both groups continued on a positive trajectory of symptom improvements (P < .0001 for reductions in PANSS total and CGI-S scores from week 12 to end of follow-up). Most patients (74% and 68% in the aripiprazole lauroxil 441 mg and 882 mg groups, respectively) achieved remission during follow-up. CONCLUSIONS These post hoc analyses of a subgroup of patients demonstrate the continued therapeutic efficacy of aripiprazole lauroxil after successful treatment of an acute episode of schizophrenia. Both the 441 mg and 882 mg groups had similar retention rates, degree of symptom improvement, and likelihood of remission. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT01469039; European Clinical Trials Database (EudraCT) numbers: 2012-003445-15 and 2012-003996-20​​​​.

Effect of patient age on treatment response in a study of the acute exacerbation of psychosis in schizophrenia

Younger patients with schizophrenia have most likely experienced fewer adverse consequences of the illness than older patients who may have experienced a lifetime of treatment as well as socio-economic problems as a consequence of the illness. There is limited information regarding differential efficacy of long-acting injectable (LAI) antipsychotic medications across the age span in patients with schizophrenia. We conducted a post hoc age and gender analysis of treatment response to aripiprazole lauroxil (AL; ARISTADA®; Alkermes, Inc.), in a 12-week, double-blind, placebo-controlled, multinational, Phase 3 study evaluating two doses of AL (441mg and 882mg) versus placebo in adult patients experiencing an acute exacerbation of schizophrenia within the previous 2months. We examined change in the total Positive and Negative Syndrome Scale (PANSS) scores from baseline using analysis of covariance and categorical treatment response (defined as ≥30% total PANSS score improvement from baseline) in the following age groups: <30, 30-39, 40-49, and 50-69years old. Age and gender did not moderate the treatment response in this study. Both AL 441mg and AL 882mg showed an early and significant improvement of the mean total PANSS scores and categorical treatment responses compared to placebo in all four age groups, including younger patients regardless of gender that was sustained over the 85-day treatment period.