Drug safety evaluation of olanzapine pamoate

Pharmacokinetic characteristics of risperidone ISM for the treatment of schizophrenia

INTRODUCTION

Risperidone-ISM is a novel intramuscular long-acting injectable formulation (LAI) of risperidone approved for the treatment of schizophrenia in adults. Knowledge regarding the pharmacokinetic properties of risperidone-ISM can improve care.

AREAS COVERED

We assessed the pharmacokinetic properties of risperidone-ISM. Most importantly, risperidone-ISM achieves therapeutic blood levels within 12-48 h after the first injection without the need for overlapping oral cotreatment, loading dose, or booster injection. Second, the in-situ microparticle (ISM) technology achieves stable blood levels, allowing currently 1-monthly injections. Third, females and patients with higher body mass index may have lower risperidone-ISM clearance, translating into higher risperidone serum levels. Fourth, there are only minimal risperidone-ISM clearance differences between deltoid and gluteal injections that balance out at steady state. However, aspects including pharmacogenetic and drug-drug interactions involving risperidone-ISM would benefit from further clarification.

EXPERT OPINION

Risperidone-ISM achieves therapeutic blood levels within 12-48 h after a single injection, currently lasting for 1 month, easing the initiation of a LAI risperidone formulation in adults with schizophrenia where LAIs remain underutilized. Prescriptions of LAIs, including risperidone-ISM, are likely to increase with an improved understanding of pharmacokinetic profiles and patient acceptability and outcomes, including in real-world settings informing drug selection.

Olanzapine-Induced Parkinsonism and Akathisia: A Case Report

This article sheds light on the case of a 22-year-old patient with paranoid schizophrenia. A treatment regimen of olanzapine (an atypical antipsychotic) of 15 mg/day was initiated for the patient and it was associated with extrapyramidal symptoms (EPS) such as drug-induced parkinsonism (DIP) and akathisia. Based on the different treatment regimens available, the patient was switched to an alternate antipsychotic along with anticholinergics, antihistamines, and benzodiazepines, following which the patient recovered well and did not report any further side effects. The highlighted case stresses the need for proper monitoring of the drug dose and sequential periodic examination of the patient to nullify the risk of adverse effects and poor compliance.

Olanzapine pamoate for the treatment of schizophrenia--a safety evaluation

INTRODUCTION

Non-adherence to long-term treatment is a major issue for patients with schizophrenia and is associated with an increased risk of relapse. Long-acting injectable (LAI) antipsychotics can offer a useful option to improve adherence. Due to the type of sustained-release mechanism, olanzapine pamoate (OLAI) can differ in safety as compared with oral olanzapine. Recent safety data concerning olanzapine pamoate required an update of previous systematic reviews.

AREAS COVERED

Safety data were found in US and EU clinical trial registries, and a literature search was undertaken using the databases PubMed and EMBASE to find all relevant published studies. Where appropriate, the number needed to harm and 95% confidence interval for categorical safety outcomes were calculated.

EXPERT OPINION

The safety profile of OLAI was similar to the well-known safety profile of oral olanzapine, except for the risk of occurrence of post-injection delirium/sedation syndrome (PDSS). Olanzapine pamoate can be a choice for schizophrenic patients with a history of response to and acceptable tolerance of oral olanzapine, who have easy access to mental healthcare settings with emergency services for the treatment of PDSS. Long-term, prospective studies assessing the efficacy and safety of OLAI and head-to-head comparisons with other LAI and oral antipsychotics are needed.

Clinical outcomes with olanzapine long-acting injection: impact of the 3-hour observation period on patient satisfaction and well-being

BACKGROUND

The objective of the present analysis is to determine the impact of the 3-hour observation period for olanzapine long-acting injection (LAI) on patient satisfaction and well-being by comparing data collected before and after its implementation.

METHODS

This is a post hoc analysis of patients treated with olanzapine LAI in 1) a 6-month fixed-dose randomized controlled trial and/or 2) a 6-year open-label safety study. This analysis was limited to patients with schizophrenia who were treated with olanzapine LAI consistent with the approved indication and dosing recommendations of the European Union Summary of Product Characteristics (N=966). Of the 966 patients, the analysis further focused only on those patients who received both 1) at least one injection before the implementation of the 3-hour observation period and 2) at least one injection after implementation of the 3-hour observation period (N=487). Patient satisfaction was assessed with the three-item Patient Satisfaction with Medication Questionnaire-Modified. Responses were averaged across all postbaseline visits occurring before (ie, without) the implementation of the 3-hour observation period and across all postbaseline visits occurring after (ie, with) the implementation of the 3-hour observation period. In addition, the rate of postinjection delirium/sedation syndrome events was calculated.

RESULTS

There was no meaningful change after implementation of the 3-hour observation period in satisfaction (before: mean [SD] =4.0 [1.02] and after: mean [SD] =4.1 [0.82]), preference for olanzapine LAI over oral medication (before: mean [SD] =4.0 [0.90] and after: mean [SD] =4.1 [0.77]), or ratings of satisfaction regarding side effects (before: mean [SD] =1.9 [0.79] and after: mean [SD] =1.8 [0.60]). For the total population (N=966), postinjection delirium/sedation syndrome occurred in 26 (0.07%) of 38,010 injections.

CONCLUSION

For patients with schizophrenia receiving treatment with olanzapine LAI, the 3-hour observation period had no impact on their satisfaction with the medication or on their subjective well-being.

Post-injection delirium/sedation syndrome in patients treated with olanzapine pamoate: mechanism, incidence, and management

Second-generation antipsychotics (SGAs) are a mainstay in the treatment of patients with schizophrenia. However, continuity in intake of the prescribed medication has been one of the greatest challenges in these patients. One option to improve medication adherence is to prescribe depot or long-acting injectable formulations (LAIs) of antipsychotics. Following risperidone, several other SGAs have been introduced as LAIs. Olanzapine pamoate, paliperidone palmitate, and aripiprazole are the new-generation LAIs, which are available for 2- to 4-week intervals of application in many countries. The literature shows a clear advantage of these drugs over placebo regarding symptom reduction and relapse prevention. LAIs show a similar safety profile to oral formulations of the relevant drug, with the exception of olanzapine pamoate, which can lead to rare cases of post-injection delirium/sedation syndrome (PDSS). PDSS is characterized by heavy sedation (possibly including coma) and/or delirium after injection. During PDSS events, patients show higher plasma concentrations of olanzapine, leading to the assumption that unintended partial intravascular injection or blood vessel injury during the injection is causative of PDSS. Therefore, a risk-management plan proposing an observation period of 3 h was introduced. In August 2013, a new proposal by the European Medicines Agency terminated the requirement to accompany these patients to their next destination, although this requirement remains in place according to US FDA recommendations.