Baseline characteristics and hospitalizations in patients with schizophrenia receiving olanzapine long-acting injection: an interim analysis from a non-interventional, prospective observational safety study.

BACKGROUND: Depot antipsychotics are a treatment option for medication nonadherence in patients with schizophrenia. Nonadherence can lead to increased relapse and hospitalization rates. This article reports hospitalization data before and after initiation of olanzapine long-acting injection (LAI), a depot antipsychotic. METHODS: Data were assessed from an ongoing, multinational, prospective, observational post-authorisation safety study being conducted to evaluate post-injection delirium/sedation syndrome (PDSS), an adverse reaction that can occur following injection of olanzapine LAI. Eligible patients were aged ≥18 years, diagnosed with schizophrenia, were prescribed olanzapine LAI, and lived outside the United States. Psychiatric hospitalization and medication data were collected retrospectively for the 6-month period before study entry and prospectively throughout the study. Paired t-tests and McNemar's tests were used to assess changes in hospitalization incidence and duration. Stepwise Cox proportional hazards models assessed factors associated with hospitalizations. Analyses were based on data from the first 3 years of the continuously enrolling study (N = 668). RESULTS: The average duration of olanzapine LAI exposure for all patients was 0.768 years. Of the 529 patients who received at least 1 injection of olanzapine LAI and were not hospitalized at study entry, 8.1% had at least 1 subsequent psychiatric hospitalization with a mean duration of 2.0 days. Of the 288 patients who had a >6-month follow-up, 8.3% had at least 1 post-baseline psychiatric hospitalization with a mean duration of 2.3 days. The incidence of hospitalizations in the 6-month period after treatment was significantly lower than that in the 6-month period prior to treatment (8.3 vs 32.6%, respectively; P < 0.001). Furthermore, mean hospitalization duration decreased from 11.5 days in the 6-month period before treatment to 2.3 days in the 6-month period after treatment (P < 0.001). Psychiatric hospitalization in the prior 12 months (P < 0.0001) and recreational drug use within 24 h of baseline visit (P = 0.015) were identified as potential predictors of time to first psychiatric hospitalization after beginning to take olanzapine LAI. At the time of interim analysis, 5 PDSS events had occurred, which was too few for a full analysis of those events. CONCLUSIONS: Results indicate a significant reduction in the incidence and days of hospitalization from the 6-month period before to the 6-month period after olanzapine LAI initiation, which suggests reduced relapse and hospitalization during treatment. Results should be interpreted with caution due to the observational nature of the study and use of retrospective baseline data.

A 6-year open-label study of the efficacy and safety of olanzapine long-acting injection in patients with schizophrenia: a post hoc analysis based on the European label recommendation.

PURPOSE: To assess the long-term efficacy and safety of olanzapine long-acting injection (LAI) in the treatment of schizophrenia, focusing on clinical trial data consistent with the approved indication and dosing recommendations in the European label and which forms the basis for treatment decisions made by clinicians in daily clinical practice. PATIENTS AND METHODS: This was a post hoc analysis of a 6-year open-label study of olanzapine LAI in patients (male or female, 18-75 years old) with schizophrenia entering this study following feeder studies of olanzapine LAI. Patients were flexibly dosed (45-405 mg, 2- to 4-week intervals), but those receiving oral olanzapine supplementation whose total olanzapine dose was >20 mg/day equivalent were excluded from this post hoc analysis. RESULTS: Data from 669 patients were analyzed (44.5% completed). Positive and Negative Syndrome Scale total scores did not change significantly from baseline to endpoint; Clinical Global Impression-Severity scores improved significantly. Mean weight change was +2.19 kg (P<0.001), with 40.8% of patients experiencing ≥7% weight gain. There were 24 occurrences of post-injection delirium/sedation syndrome (PDSS). CONCLUSION: Olanzapine LAI appeared to be effective in the long-term maintenance of schizophrenia, and the safety profile was consistent with that of oral olanzapine, except for injection-related events and PDSS events.

Within-drug benefit-risk evaluation of olanzapine long-acting injection at one and two years of treatment.

We sought to evaluate the within-drug benefit-risk of olanzapine long-acting injection (LAI) using both quantitative and qualitative methods. Subjects included 1192 adult patients with schizophrenia or schizoaffective disorder who participated in clinical trials with the opportunity for at least two years of continuous treatment with olanzapine LAI (45-405 mg every two to four weeks). Using the Benefit Risk Action Team (BRAT) framework, we evaluated frequency versus duration of benefits and risks commonly observed with atypical antipsychotics. We then used the Transparent Uniform Risk/Benefit Overview (TURBO) method, which weighs the drug's two most medically serious and/or frequent adverse events versus its primary benefit (effectiveness) and an ancillary benefit. The most frequent events among all patients were remaining free of relapse (91.4% for an average of 306 days at one year, 88.4% for 546 days at two years) and symptomatic remission (81.7% for an average of 239 days at one year, 84.1% for 438 days at two years). One- and two-year incidence of ≥7% weight gain was 33.3% and 41.7%. Incidences for sexual dysfunction, hyperprolactinemia, and post-injection delirium/sedation syndrome (PDSS) were <2%. TURBO ratings unanimously selected PDSS and weight gain as key risks and resulted in an average score in the acceptable benefit-risk balance range.

Long-term safety and efficacy of olanzapine long-acting injection in patients with schizophrenia or schizoaffective disorder: a 6-year, multinational, single-arm, open-label study.

The objective of this study was to assess the long-term safety and efficacy of olanzapine long-acting injection (LAI). A 6-year, single-arm, open-label extension study of olanzapine LAI was conducted at 127 sites in 25 countries. Patients were 18-76 years of age, were diagnosed with schizophrenia or schizoaffective disorder (N=931), and had been previously enrolled in one of three clinical trials of olanzapine LAI. Patients received flexibly dosed (45-405 mg) olanzapine LAI every 2-4 weeks. The mean duration of exposure was ∼3 years. A total of 393 (42.2%) patients completed the study. The mean weight change was +2.1 kg (P<0.001), with 40.6% of patients experiencing 7% or higher weight gain. Treatment-emergent categorical changes occurred in fasting glucose, total cholesterol, and triglyceride levels. Pharmacokinetic analyses revealed no systemic accumulation of olanzapine after long-term treatment. There were 36 occurrences of post-injection delirium/sedation syndrome, all resolving within 72 h. The mean Positive and Negative Syndrome Scale total and subscale scores did not change significantly over the course of the study, indicating clinical stability. Olanzapine LAI appeared effective as a long-term maintenance treatment, with a safety profile generally consistent with the known profile of oral olanzapine, except for injection-related events (including post-injection delirium/sedation syndrome).

Safety and efficacy of olanzapine in the long-term treatment of Japanese patients with bipolar I disorder, depression: an integrated analysis.

AIM: Safety and efficacy of long-term olanzapine treatment in Japanese patients with bipolar depression were assessed. METHODS: An integrated analysis of data from two studies was performed in olanzapine-treated patients (n = 165) with bipolar depression. Study 1 was a 6-week, double-blind, global study. Patients were randomly assigned to olanzapine or placebo followed by 18 weeks of open-label treatment. Study 2 was an open-label extension of Study 1 involving only Japanese patients. Patients assigned to Pre-olanzapine and Pre-placebo in Study 1 were treated for 24 weeks (total olanzapine exposure 42 or 48 weeks) and newly recruited patients (New-olanzapine) were treated for 48 weeks. Safety outcomes included treatment-emergent adverse events and changes in metabolic parameters. Efficacy outcome was assessed with Montgomery-Åsberg Depression Rating Scale score. RESULTS: Forty-three percent of patients completed the 42- or 48-week olanzapine treatment period. The most common treatment-emergent adverse event was weight increased (47.9%). Significant increases were seen in weight (3.5 kg), and in fasting glucose (3.5 mg/dL), fasting total cholesterol (8.1 mg/dL), and fasting triglycerides (35.1 mg/dL). Remission rates (Montgomery-Åsberg Depression Rating Scale total score ≤12 at any time) were 79.8% for the Pre-olanzapine group, 90.2% for the Pre-placebo group, and 85.0% for the New-olanzapine group. No patents developed mania during treatment. CONCLUSIONS: Long-term use of olanzapine in a Japanese population with bipolar depression is associated with increases in weight and fasting metabolic measures, and also with improved depressive symptoms with avoidance of mania. Clinicians must carefully consider the benefits and risks of long-term therapy with olanzapine.

A pooled analysis of injection site-related adverse events in patients with schizophrenia treated with olanzapine long-acting injection.

BACKGROUND: Depot antipsychotic injections are an important tool for the management of patients with schizophrenia who have difficulty with adherence to oral medication. However, pain and discomfort at the injection site can be a potential impediment to the use of these long-acting formulations. We report here the results of a pooled analysis of injection site-related adverse events (AEs) collected during treatment with the olanzapine long-acting injection (olanzapine LAI). METHODS: Unsolicited injection site-related AEs were pooled from 7 olanzapine LAI clinical trials conducted in patients between March 2001 and December 2010. All patients had a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) or Fourth Edition, Text Revision (DSM-IV-TR) diagnosis of schizophrenia or schizoaffective disorder and were between the ages of 18 and 75. Doses ranged from 45 to 405 mg olanzapine LAI, and injection intervals were 2, 3, or 4 weeks. Events were evaluated for severity, timing, possible risk factors, and outcome. A criterion of p < .05 for statistical significance was used for all tests. RESULTS: A total of 1752 patients received at least 1 olanzapine LAI injection. Of these, 92 patients (5.3%) reported at least 1 injection site-related AE, with "pain" being the most common type (2.9%). Most events were mild (81.4%) and the median duration was 3 days. Four patients (0.2%) discontinued due to injection site-related AEs. Dose volume and body mass index did not appear to affect the probability of injection site-related AEs. However, patients who experienced a post-injection delirium/sedation syndrome event (n = 37) were more likely to have or have had an injection site-related AE at some time during the study. Incidence of injection site-related AEs appeared to decrease over time. In 94.2% of the injection site-related AEs, no specific treatment or concomitant medication was reported; in 9 cases, patients received pharmacologic treatment for reaction, mass, abscess, rash, or pain. CONCLUSIONS: Injection site-related AEs with olanzapine LAI were generally mild. The incidence and nature of these injection site-related AEs were generally similar to those occurring during treatment with other injectable antipsychotics. TRIAL REGISTRATION: ClinicalTrials.gov ID; URL: NCT00094640, NCT00088478, NCT00088491, NCT00088465, and NCT00320489.

Incidences of extrapyramidal symptoms in patients with schizophrenia after treatment with long-acting injection (depot) or oral formulations of olanzapine.

BACKGROUND: The incidence of extrapyramidal symptoms (EPS) has been shown to be generally low among patients with schizophrenia receiving oral olanzapine. A long-acting injection (LAI) of olanzapine has recently been approved for the treatment of schizophrenia in a number of countries. Accordingly, the objective of the current analyses was to compare the incidences of EPS during treatment with olanzapine LAI versus oral olanzapine. METHODS: The incidences of treatment-emergent EPS were examined in adults with schizophrenia receiving olanzapine LAI or oral olanzapine for up to 3 years. Short-term data were obtained from two double-blind studies of olanzapine LAI: one included a placebo comparator, and the other included oral olanzapine as an active comparator. Long-term data were obtained from an open-label extension study for olanzapine LAI and from an integrated database for oral olanzapine. RESULTS: The short-term incidence of EPS was 5.6% during treatment with olanzapine LAI (45-405 mg every 2-4 weeks) and 5.0% with oral olanzapine (5-20 mg/day). Akathisia (2.6% LAI, 1.2% oral), and Parkinson-like symptoms (1.8% LAI, 3.7% oral) were similar between treatment groups. The incidence of EPS for long-term treatment was 9.2% for olanzapine LAI. Incidences of EPS events were not significantly different between patients receiving olanzapine LAI or oral olanzapine for up to 3 years. CONCLUSIONS: These findings suggest that EPS profiles are similar for olanzapine LAI and oral olanzapine.

Efficacy and safety of olanzapine for treatment of patients with bipolar depression: Japanese subpopulation analysis of a randomized, double-blind, placebo-controlled study.

BACKGROUND: The efficacy and safety of olanzapine monotherapy are evaluated in Japanese patients from a large, global study of bipolar depression. METHODS: This is an analysis of Japanese patients from a 6-week, global (Japan, China, Korea, Taiwan, and the United States), randomized, double-blind, placebo-controlled, Phase 3 study of patients with a depressive episode of bipolar I disorder. The primary outcome was baseline-to-endpoint change in the Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Secondary outcome measures included the Clinical Global Impressions-Bipolar Version Severity of Illness Scale (CGI-BP), the 17-item Hamilton Depression Rating Scale (HAMD-17) total score, the Young Mania Rating Scale (YMRS) total score, and rates of response (≥50% baseline-to-endpoint reduction in MADRS total score), recovery, and remission. RESULTS: Of the 156 Japanese patients, 104 had been allocated to olanzapine and 52 to placebo. All results are baseline-to-endpoint change. Compared to placebo, patients in the olanzapine group experienced greater improvement in the primary outcome measure, MADRS total score (-14.9 vs. -10.7; p = .01). They also had greater reductions in the following secondary measures: CGI- BP Depression (-1.41 vs. -0.89; p = .008), CGI-BP Bipolar (-1.31 vs. -0.83; p = .01), HAMD-17 (-11.7 vs. -7.9; p < .01), and YMRS (-0.32 vs. 0.34; p = .03). Differences in rates of response, recovery, and remission were not statistically significant. A greater proportion of olanzapine-treated patients reported treatment- emergent adverse events (87.5% vs. 59.6%; p < .001). Patients treated with olanzapine had greater increases in weight (p < .001) and fasting total cholesterol (p = .008); fasting triglycerides (p = .02), and fasting low-density lipoprotein (p = .01). There was a greater reduction in fasting high-density lipoprotein in olanzapine-treated patients (p = .01). Compared with placebo-group patients, more olanzapine-group patients shifted from borderline to high cholesterol (25.0% vs. 0.0%; p = .007) and had clinically significant weight gain (≥7% body weight) (20.2% vs. 1.9%; p = .001). CONCLUSIONS: Results of this analysis support the efficacy and tolerability of olanzapine for the treatment of bipolar depression in Japanese patients. Results in this population were consistent with those seen in the more ethnically diverse parent study. In making treatment decisions for individual patients, clinicians should carefully consider the risks and benefits of olanzapine treatment. TRIAL REGISTRATION: Clinicatrials.gov ID NCT00510146 Olanzapine Treatment of Patients with Bipolar I Disorder.

Randomised, double-blind, placebo-controlled study of olanzapine in patients with bipolar I depression.

BACKGROUND: Atypical antipsychotics are widely used in bipolar mania. However, the efficacy of atypical antipsychotics in bipolar depression has not been comprehensively explored. AIMS: To evaluate olanzapine monotherapy in patients with bipolar depression. METHOD: Patients with bipolar depression received olanzapine (5-20 mg/day, n = 343) or placebo (n = 171) for 6 weeks. The primary outcome was change from baseline to end-point in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Secondary outcomes included: Clinical Global Impression - Bipolar Version (CGI-BP) scale, 17-item Hamilton Rating Scale for Depression (HRSD-17) and Young Mania Rating Scale (YMRS) scores, and the rate of response (≥50% reduction in MADRS at end-point), recovery (MADRS ≤12 for ≥4 weeks plus treatment completion) and remission (MADRS ≤8). The trial was registered with ClinicalTrials.gov (NCT00510146). RESULTS: Olanzapine demonstrated: significantly greater (P<0.04) improvements on MADRS (least-squares mean change -13.82 v. -11.67), HRSD-17 and YMRS total scores and all CGI-BP subscale scores v. placebo; significantly (P≤0.05) more response and remission, but not recovery; significantly (P<0.01) greater mean increases in weight, fasting cholesterol and triglycerides; and significantly more (P<0.001) patients gained ≥7% body weight. CONCLUSIONS: Olanzapine monotherapy appears to be efficacious in bipolar depression. Additional long-term studies are warranted to confirm these results. Safety findings were consistent with the known safety profile of olanzapine.

Treatment-completion rates with olanzapine long-acting injection versus risperidone long-acting injection in a 12-month, open-label treatment of schizophrenia: indirect, exploratory comparisons.

BACKGROUND: Little is known about the comparative effectiveness of atypical antipsychotics in long-acting injection formulation. Due to the absence of head-to-head studies comparing olanzapine long-acting injection and risperidone long-acting injection, this study was intended to make exploratory, indirect, cross-study comparisons between the long-acting formulations of these two atypical antipsychotics in their effectiveness in treating patients with schizophrenia. METHODS: Indirect, cross-study comparisons between olanzapine long-acting injection and risperidone long-acting injection used 12-month treatment-completion rates, because discontinuation of an antipsychotic for any cause is a recognized proxy measure of the medication's effectiveness in treating schizophrenia. Following a systematic review of the literature, two indirect comparisons were conducted using open-label, single-cohort studies in which subjects were stabilized on an antipsychotic medication before depot initiation. The first analysis compared olanzapine long-acting injection (one study) with pooled data from nine identified risperidone long-acting injection studies. The second analysis was a "sensitivity analysis," using only the most similar studies, one for olanzapine long-acting injection and one for risperidone long-acting injection, which shared near-identical study designs and involved study cohorts with near-identical patient characteristics. Pearson Chi-square tests assessed group differences on treatment-completion rates. RESULTS: Comparison of olanzapine long-acting injection data (931 patients) with the pooled data from the nine risperidone long-acting injection studies (3950 patients) provided almost identical 12-month treatment-completion rates (72.7% versus 72.4%; P = 0.87). When the two most similar studies were compared, the 12-month completion rate for olanzapine long-acting injection was significantly higher than for risperidone long-acting injection (81.3% versus 47.0%; P < 0.001). However, any conclusions drawn from this comparison may be limited by differences in the studies' geographic catchment areas. CONCLUSION: Using treatment-completion rates as a proxy measure of medication effectiveness, olanzapine long-acting injection did not differ significantly from risperidone long-acting injection when including all eligible studies. However, the findings of this exploratory analysis should be interpreted with caution, considering the methodological limitations of these indirect, cross-study comparisons.

Early response predicts subsequent response to olanzapine long-acting injection in a randomized, double-blind clinical trial of treatment for schizophrenia.

BACKGROUND: In patients with schizophrenia, early non-response to oral antipsychotic therapy robustly predicts subsequent non-response to continued treatment with the same medication. This study assessed whether early response predicted later response when using a long-acting injection (LAI) antipsychotic. METHODS: Data were taken from an 8-week, randomized, double-blind, placebo-controlled study of olanzapine LAI in acutely ill patients with schizophrenia (n = 233). Early response was defined as ≥ 30% improvement from baseline to Week 4 in Positive and Negative Syndrome Scale (PANSS0-6) Total score. Subsequent response was defined as ≥ 40% baseline-to-endpoint improvement in PANSS0-6 Total score. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and predictive accuracy were calculated. Clinical and functional outcomes were compared between Early Responders and Early Non-responders. RESULTS: Early response/non-response to olanzapine LAI predicted later response/non-response with high sensitivity (85%), specificity (72%), PPV (78%), NPV (80%), and overall accuracy (79%). Compared to Early Non-responders, Early Responders had significantly greater improvement in PANSS0-6 Total scores at all time points and greater baseline-to-endpoint improvement in PANSS subscale scores, Quality of Life Scale scores, and Short Form-36 Health Survey scores (all p ≤ .01). Among Early Non-responders, 20% demonstrated response by Week 8. Patients who lacked early improvement (at Week 4) in Negative Symptoms and Disorganized Thoughts were more likely to continue being non-responders at Week 8. CONCLUSIONS: Among acutely ill patients with schizophrenia, early response predicted subsequent response to olanzapine LAI. Early Responders experienced significantly better clinical and functional outcomes than Early Non-responders. Findings are consistent with previous research on oral antipsychotics. CLINICAL TRIALS REGISTRY: F1D-MC-HGJZ: Comparison of Intramuscular Olanzapine Depot With Placebo in the Treatment of Patients With Schizophrenia http://clinicaltrials.gov/ct2/show/NCT00088478?term=olanzapine+depot&rank=3Registry identifier - NCT00088478.

Comparison of metabolic changes in patients with schizophrenia during randomized treatment with intramuscular olanzapine long-acting injection versus oral olanzapine.

Metabolic changes were examined in patients with schizophrenia during treatment with either oral olanzapine or olanzapine long-acting injection (LAI). Data were collected from patients who had been stabilized on oral olanzapine (10, 15, or 20 mg/day) for ≥4 weeks and then randomized to either continued olanzapine oral treatment (n = 322) or LAI (n = 599; 150 mg/2 weeks, 405 mg/4 weeks, or 300 mg/2 weeks) for up to 24 weeks. Mean and categorical changes in metabolic parameters were analyzed. Mean changes in weight, glucose, and most lipids were generally not significantly different between treatment groups. Weight changes over time followed similar patterns and were not significantly different at endpoint between the two treatment-formulation groups. Low-density lipoprotein cholesterol decreased significantly less among olanzapine LAI-treated patients. Percentages of patients with potentially clinically significant changes in blood glucose and lipid concentrations were similar for the two treatments. Percentages of patients experiencing adverse events related to weight, diabetes, or dyslipidemia were also not significantly different between treatments. Metabolic changes in patients with schizophrenia appeared generally similar during treatment with oral olanzapine or olanzapine LAI.

Dose-associated changes in safety and efficacy parameters observed in a 24-week maintenance trial of olanzapine long-acting injection in patients with schizophrenia.

BACKGROUND: In a recently published 24-week maintenance study of olanzapine long-acting injection (LAI) in schizophrenia (Kane et al., 2010), apparent dose-associated changes were noted in both efficacy and safety parameters. To help clinicians balance safety and efficacy when choosing a dose of olanzapine LAI, we further studied these changes. METHODS: Outpatients with schizophrenia who had maintained stability on open-label oral olanzapine for 4 to 8 weeks were randomly assigned to "low" (150 mg/2 weeks; N = 140), "medium" (405 mg/4 weeks; N = 318), or "high" (300 mg/2 weeks; N = 141) dosages of olanzapine LAI for 24 weeks. Potential relationships between dose and several safety or efficacy measures were examined via regression analysis, the Jonckheere-Terpstra test (continuous data), or the Cochran-Armitage test (categorical data). RESULTS: Safety parameters statistically significantly related to dose were mean weight change (low: +0.67 [SD = 4.38], medium: +0.89 [SD = 3.87], high: +1.70 [SD = 4.14] kg, p = .024; effect size [ES] = 0.264 high vs. low dose), mean change in prolactin (low: -5.61 [SD = 12.49], medium: -2.76 [SD = 19.02]), high: +3.58 [SD = 33.78] µg/L, p = .001; ES = 0.410 high vs. low dose), fasting triglycerides change from normal at baseline to high (low: 3.2%, medium: 6.0%, high: 18.9%, p = .001; NNT = 7 high vs. low dose) and fasting high-density lipoprotein cholesterol change from normal at baseline to low (low: 13.8%, medium: 19.6%, high: 30.7%, p = .019; NNT = 6 high vs. low dose). Efficacy measures significantly related to dose included Positive and Negative Syndrome Scale total score mean change (low: +2.66 [SD = 14.95], medium: -0.09 [SD = 13.47], high: -2.19 [SD = 13.11], p <.01; ES = 0.356 high vs. low dose), relapse rate (low: 16%, medium: 10%, high: 5%, p = .003; NNT = 9 high vs. low dose), all-cause discontinuation rate (low: 36%, medium: 30%, high: 24%, p = .037; NNT = 9 high vs. low dose), and rate of discontinuation due to efficacy-related reasons (low: 20%, medium: 14%, high: 6%, p <.001). Time to all-cause discontinuation (p = .035) and time to relapse (p = .005) were also significantly related to dose. CONCLUSIONS: Analyses of several safety and efficacy parameters revealed significant associations with dose of olanzapine LAI, with the highest dose generally showing greater efficacy as well as greater adverse changes in metabolic safety measures. When considering olanzapine LAI, as with all antipsychotics, it is important to carefully consider the potential benefits and risks for an individual patient. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00088491.

Post-injection delirium/sedation syndrome in patients with schizophrenia treated with olanzapine long-acting injection, I: analysis of cases.

BACKGROUND: An advance in the treatment of schizophrenia is the development of long-acting intramuscular formulations of antipsychotics, such as olanzapine long-acting injection (LAI). During clinical trials, a post-injection syndrome characterized by signs of delirium and/or excessive sedation was identified in a small percentage of patients following injection with olanzapine LAI. METHODS: Safety data from all completed and ongoing trials of olanzapine LAI were reviewed for possible cases of this post-injection syndrome. Descriptive analyses were conducted to characterize incidence, clinical presentation, and outcome. Regression analyses were conducted to assess possible risk factors. RESULTS: Based on approximately 45,000 olanzapine LAI injections given to 2054 patients in clinical trials through 14 October 2008, post-injection delirium/sedation syndrome occurred in approximately 0.07% of injections or 1.4% of patients (30 cases in 29 patients). Symptomatology was consistent with olanzapine overdose (e.g., sedation, confusion, slurred speech, altered gait, or unconsciousness). However, no clinically significant decreases in vital signs were observed. Symptom onset ranged from immediate to 3 to 5 hours post injection, with a median onset time of 25 minutes post injection. All patients recovered within 1.5 to 72 hours, and the majority continued to receive further olanzapine LAI injections following the event. No clear risk factors were identified. CONCLUSIONS: Post-injection delirium/sedation syndrome can be readily identified based on symptom presentation, progression, and temporal relationship to the injection, and is consistent with olanzapine overdose following probable accidental intravascular injection of a portion of the olanzapine LAI dose. Although there is no specific antidote for olanzapine overdose, patients can be treated symptomatically as needed. Special precautions include use of proper injection technique and a post-injection observation period. TRIAL REGISTRATION: ClinicalTrials.gov ID; URL: http://http//www.clinicaltrials.gov/: NCT00094640, NCT00088478, NCT00088491, NCT00088465, and NCT00320489.

Post-injection delirium/sedation syndrome in patients with schizophrenia treated with olanzapine long-acting injection, II: investigations of mechanism.

BACKGROUND: Olanzapine long-acting injection (LAI) is a salt-based depot antipsychotic combining olanzapine and pamoic acid. The slow intramuscular dissolution of this practically insoluble salt produces an extended release of olanzapine lasting up to 4 weeks. However, in a small number of injections (< 0.1%), patients experienced symptoms suggestive of olanzapine overdose, a phenomenon that has been termed "post-injection delirium/sedation syndrome" (PDSS). The authors conducted a series of parallel investigations into the possible reasons PDSS events occur. METHODS: Healthcare providers involved in the PDSS cases were queried for clinical information around the events. Plasma samples from patients experiencing PDSS were collected when possible (12/30 cases) and olanzapine concentrations compared with the known pharmacokinetic profile for olanzapine LAI. Product batches and used vials from the PDSS cases were evaluated for compliance with established manufacturing standards and/or possible user error. Because this depot formulation depends upon slow dissolution at the intramuscular injection site, in-vitro experiments were conducted to assess solubility of olanzapine pamoate in various media. RESULTS: Injection administrators reported no unusual occurrences during the injection. No anomalies were found with the product batches or the remaining suspension in the used vials. Olanzapine concentrations during PDSS events were higher than the expected 5-73 ng/mL range, with concentrations exceeding 100 ng/mL and in some cases reaching >600 ng/mL during the first hours after injection but then returning to the expected therapeutic range within 24 to 72 hours. Solubility and dissolution rate of olanzapine pamoate were also found to be substantially greater in plasma than in other media such as those approximating the environment in muscle tissue. CONCLUSIONS: Manufacturing irregularities, improper drug reconstitution, and inappropriate dosing were ruled out as possible causes of PDSS. In-vitro solubility and in-vivo pharmacokinetic investigations suggest that PDSS is related to exposure of the injected product to a substantial volume of blood. This exposure is most likely the result of unintended partial intravascular injection or blood vessel injury during the injection (occurring even with proper injection technique) with subsequent seepage of the medication into the vasculature, which would produce higher than intended olanzapine concentrations and symptoms consistent with PDSS. TRIAL REGISTRATION: ClinicalTrials.gov ID; URL: http://http//www.clinicaltrials.gov/: NCT00094640, NCT00088478, NCT00088491, NCT00088465, and NCT00320489.