Post authorization safety study comparing quetiapine to risperidone and olanzapine

Pharmacokinetic Prediction of Immediate- and Extended-Release Tablets for Patients with Liver Disease Using Whole Body Physiologically-Based Pharmacokinetic Modeling for the Antipsychotic Drug Quetiapine

Although quetiapine metabolism occurs extensively in the liver and careful dosing is recommended in patients with liver disease, there has been a paucity of pharmacometric studies to adjust the clinical dose of quetiapine according to liver-disease severity. This study aimed to establish a whole-body, physiologically-based pharmacokinetic (WB-PBPK) model to explain interindividual variability in quetiapine PK and quantitatively predict PK in patients with liver disease. The developed WB-PBPK model well described the PK characteristics of different quetiapine regimens in healthy populations. The PK predictions could also be applied to patients with schizophrenia (without significant differences from healthy subjects). For the same total dose of quetiapine, both immediate-release (IR) and extended-release (ER) tablets showed significantly increased exposure and decreased clearance in patients with liver disease compared to healthy subjects. The model showed that steady-state plasma quetiapine concentrations exceeded the usual therapeutic range after multiple doses of IR tablets 250 mg three times daily or ER tablets 800 mg once daily in patients with liver disease. Therefore, the doses of quetiapine IR or ER tablets could be reduced by 0.10-0.50 times depending on liver-disease severity, so that mean steady-state plasma concentrations could be positioned near the therapeutic range. WB-PBPK modeling for quetiapine enabled quantitative prediction of PK according to IR or ER formulation and liver-disease severity. The results of this study provide useful data for improving the therapeutic use of quetiapine by enabling dose selection based on formulation and liver-disease severity.

Association between selective serotonin reuptake inhibitor and risk of peripheral artery disease in diabetes mellitus: Propensity score matching and landmark analysis

An increasing number of studies have demonstrated the bidirectional hemostatic effect of selective serotonin reuptake inhibitors (SSRIs) on the risk of cerebrovascular and cardiovascular diseases. However, no previous study has focused on the relationship between SSRI and the risk of peripheral artery disease (PAD) in diabetes mellitus (DM). We sought to evaluate the association between SSRIs and the PAD risk in individuals with DM.We conducted a retrospective, population-based cohort study using data from the Longitudinal Health Insurance Database from 1999 to 2010 in Taiwan. A total of 5049 DM patients were included and divided into 2 groups: DM with SSRI users and DM with SSRI non-users. Propensity score matching and 1-year landmark analysis were used for our study design. Stratified Cox proportional hazard regressions were used to analyze the hazard ratio of the PAD risk in certain subgroups.DM with SSRI users did not affect the PAD risk compared to DM with SSRI non-users. These findings were consistent with all sensitivity analyses (i.e., age, sex, SSRI doses, antithrombotic medication use, and medical and psychiatric comorbidities).In this study, we found that there was no significant difference of PAD risk between DM with SSRI users and DM with SSRI non-users. DM with SSRI user did not affect PAD risk across any SSRI dose, age, sex, antithrombotic medications, and multiple comorbidities in the subgroup analysis.

Drug Repurposing for the Management of Depression: Where Do We Stand Currently?

A slow rate of new drug discovery and higher costs of new drug development attracted the attention of scientists and physicians for the repurposing and repositioning of old medications. Experimental studies and off-label use of drugs have helped drive data for further studies of approving these medications. A deeper understanding of the pathogenesis of depression encourages novel discoveries through drug repurposing and drug repositioning to treat depression. In addition to reducing neurotransmitters like epinephrine and serotonin, other mechanisms such as inflammation, insufficient blood supply, and neurotoxicants are now considered as the possible involved mechanisms. Considering the mentioned mechanisms has resulted in repurposed medications to treat treatment-resistant depression (TRD) as alternative approaches. This review aims to discuss the available treatments and their progress way during repositioning. Neurotransmitters' antagonists, atypical antipsychotics, and CNS stimulants have been studied for the repurposing aims. However, they need proper studies in terms of formulation, matching with regulatory standards, and efficacy.

Dose-response association of acute-phase quetiapine treatment with risk of new-onset hypothyroidism in schizophrenia patients

AIMS

To assess association between quetiapine treatment and risk of new-onset hypothyroidism in schizophrenia patients.

METHODS

We conducted a retrospective cohort study in a tertiary hospital in China between January 2016 and December 2018. Schizophrenia patients with normal thyroid tests at admission were included. Hypothyroidism, which was defined as thyroid-stimulating hormone >4.20 mU/L and free thyroxine <12.00 pmol/L, or on L-thyroxine prescriptions, was the outcome measure, and quetiapine treatment between admission and subsequent thyroid test was the exposure measure of this study. Adjusted relative risks and 95% confidence intervals were used to assess the independent association of quetiapine treatment with risk of new-onset hypothyroidism. The dose-response association was further analysed by 3 quetiapine doses: low (≤<=0.2 g/d), medium (0.2-0.6 g/d), and high (>0.6 g/d).

RESULTS

A total of 2022 eligible patients were included in the final analysis. Sixty patients (15.0%) in the quetiapine group developed hypothyroidism, while 56 patients (3.5%) in the nonquetiapine group developed hypothyroidism. Relative risk (95% confidence interval) of developing hypothyroidism for quetiapine use was 4.01 (2.86-5.64) after adjusting for several potential confounding factors. A strong dose-response association between quetiapine use and risk of developing hypothyroidism was observed: adjusted relative risks (95% confidence intervals) were 1.00 (0.25-2.59), 4.22 (2.80-6.25) and 5.62 (3.66-8.38), respectively, for low-, medium- and high-dose quetiapine, as compared with no quetiapine.

CONCLUSION

Acute phase quetiapine treatment for schizophrenia patients was strongly associated with increased risk of developing new-onset hypothyroidism, with a clear dose-response association.