Systematic review and meta-analysis on the therapeutic reference range for escitalopram: Blood concentrations, clinical effects and serotonin transporter occupancy

Unveiling potential adverse events associated with escitalopram oxalate: A real-world analysis based FDA adverse event reporting system database

OBJECTIVE

The study aimed to conduct a multidimensional evaluation of potential adverse events (AEs) of escitalopram oxalate based on the FDA adverse event reporting system (FAERS) database.

METHODS

This study utilized the reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma-poisson shrinker (MGPS) to mine and analyze data from the FAERS database from the first quarter of 2004 to the second quarter of 2023.

RESULTS

There was a total of 19,854 AE reports related to escitalopram oxalate, extracting 625 preferred terms (PTs), and covering 27 system organ classes (SOCs). The results showed that the number of reports by females was significantly higher than males, accounting for 57.68%. The reporting number was higher in 2018 and 2019, accounting for 9.50% and 10.18% of the total reports, respectively. The main reporters were consumers and other health professionals, accounting for 26.99% and 26.75% respectively. The majority of the reports were primarily from the United States. Newly emerging AE signals such as intentional overdose (n = 691, ROR 8.51, PRR 8.45, IC 3.05, Empirical Bayesian Geometric Mean (EBGM) 8.35), suicide attempt (n = 665, ROR 8.58, PRR 8.52, IC 3.06, EBGM 8.42), serum serotonin (n = 5, ROR 1044.78, PRR 1044.71, IC 2.56, EBGM 392.39), anti-actin antibody positive (n = 5, ROR 626.87, PRR 626.83, IC 2.56, EBGM 313.91), among others, were not mentioned in the drug's label.

CONCLUSION

While escitalopram oxalate has clear benefits in the treatment of depression and other mental health disorders, the presence of AEs also suggests risks associated with its use. Particularly concerning are risks of suicide and changes in serum serotonin levels.

Assessing Pharmacokinetic Correlates of Escitalopram-Related Adverse Drug Reactions

BACKGROUND

To assess the pharmacokinetic correlates of reported adverse drug reactions (ADRs) under antidepressant treatment with escitalopram (ESC) using a large therapeutic drug monitoring database.

METHODS

A large naturalistic sample of inpatients and outpatients prescribed ESC was analyzed. ADRs were classified using the Udvalg for Kliniske Undersogelser side effect rating scale. We compared ESC-treated patients with (n = 35) and without ADRs (n = 273) using ESC plasma concentrations as the primary outcome. We also compared ADR rates in the 2 groups based on 2 cut-off ESC levels reflecting the recommended upper thresholds of the therapeutic reference range of 80 ng/mL, suggested by the consensus therapeutic drug monitoring guidelines, and 40 ng/mL, based on recent meta-analysis data. The effects of age, sex, smoking, daily ESC dose, plasma concentrations, and concentrations corrected for daily dose were included in a binary logistic regression model to predict ADRs.

RESULTS

No differences in clinical, demographic, or pharmacokinetic parameters were observed between patients with and without ADRs ( P > 0.05). Patients with ESC-related ADRs were more frequently diagnosed with psychotic disorders than those without (25% vs. 7.1%, P = 0.004). None of the variables was associated with ADR risk. Overall, ADR rates were not significantly different in patients above versus below thresholds of ESC concentrations (ESC concentrations >40 [n = 59] vs. ≤40 ng/mL [n = 249] and >80 [n = 8] vs. ≤80 ng/mL [n = 300]; P = 0.56 and P = 1.0, respectively).

CONCLUSIONS

No distinct pharmacokinetic patterns underlying ESC-associated ADRs were observed. Further studies with more specific assessments of ADRs in larger cohorts are required to better identify potential underlying patterns.

Update Lessons from PET Imaging Part II: A Systematic Critical Review on Therapeutic Plasma Concentrations of Antidepressants

BACKGROUND

Compared with antipsychotics, the relationship between antidepressant blood (plasma or serum) concentrations and target engagement is less well-established.

METHODS

We have discussed the literature on the relationship between plasma concentrations of antidepressant drugs and their target occupancy. Antidepressants reviewed in this work are citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine, duloxetine, milnacipran, tricyclic antidepressants (amitriptyline, nortriptyline, and clomipramine), bupropion, tranylcypromine, moclobemide, and vortioxetine. Four electronic databases were systematically searched.

RESULTS

We included 32 articles published 1996-2022. A strong relationship between serotonin transporter (SERT) occupancy and drug concentration is well established for selective serotonin reuptake inhibitors. Lower limits of recommended therapeutic reference ranges largely corroborate with the findings from positron emission tomography studies (80% SERT occupancy). Only a few novel studies have investigated alternative targets, that is, norepinephrine transporters (NETs), dopamine transporters (DATs), or monoamine oxidase A (MAO-A). For certain classes of drugs, positron emission tomography study data are inconclusive. Low DAT occupancy after bupropion treatment speculates its discussed mechanism of action. For MAO inhibitors, a correlation between drug concentration and MAO-A occupancy could not be established.

CONCLUSIONS

Neuroimaging studies are critical in TDM-guided therapy for certain antidepressants, whereas for bupropion and MAO inhibitors, the available evidence offers no further insight. Evidence for selective serotonin reuptake inhibitors is strong and justifies a titration toward suggested ranges. For SNRIs, duloxetine, and venlafaxine, NETs are sufficiently occupied, well above the SERT efficacy threshold. For these drugs, a titration toward higher concentrations (within the recommended range) should be considered in case of no response at lower concentrations.

Pharmacokinetic correlates of clinical response in a naturalistic sample of escitalopram-treated patients

OBJECTIVE

We assessed pharmacokinetic correlates of treatment response to escitalopram using a large therapeutic drug monitoring database.

METHODS

A large naturalistic sample of patients receiving escitalopram was analyzed. Responders were defined as 'very much improved' or 'much improved' based on the Clinical Global Impression - Improvement score, CGI-I. We compared responders (n = 83) vs. non-responders (n = 388) with the primary outcome being the escitalopram plasma concentration and concentration corrected by the daily dose (C/D ratio). Effects of age, sex, body-mass-index (BMI), and C/D ratio were assessed in a multivariate logistic regression model predicting response.

RESULTS

There were no statistically significant differences in clinical and demographic characteristics between responders vs. non-responders. There were also no differences between escitalopram daily doses or plasma concentrations, while C/D ratios were significantly higher in non-responders than in responders (1.6 ± 1.7 vs. 1.2 ± 0.9 (ng/mL)/(mg/day), p = 0.007); C/D ratios (odds ratio 0.52, 95% confidence interval 0.34-0.80, p < 0.003) were associated with response to escitalopram, after controlling for age, sex, and BMI.

CONCLUSIONS

Patients with low clearance of escitalopram as reflected upon high C/D ratios may be less likely respond to escitalopram. Identifying these patients during dose titration may support clinical decision-making, including switching to a different antidepressant instead of increasing daily dose.

Effects of Sleeve Gastrectomy and Roux-en-Y Gastric Bypass on Escitalopram Pharmacokinetics: A Cohort Study

BACKGROUND

Changes in the gastrointestinal physiology after bariatric surgery may affect the pharmacokinetics of medications. Data on the impact of different surgical techniques on the pharmacokinetics of commonly prescribed antidepressants such as escitalopram are limited.

METHODS

This case-only prospective study investigated escitalopram-treated patients who underwent bariatric surgery at hospitals in Central Norway. Escitalopram concentrations were assessed using serial blood samples obtained during a dose interval of 24 hours preoperatively and at 1, 6, and 12 months, postoperatively. The primary outcomes were changes in the area under the time-concentration curve (AUC 0-24 ) with secondary outcomes, including full pharmacokinetic profiling. We performed repeated-measures analysis of variance for the AUC 0-24 and secondary outcomes.

RESULTS

Escitalopram-treated obese patients who underwent sleeve gastrectomy (n = 5) and Roux-en-Y gastric bypass (n = 4) were included. Compared with preoperative baseline, dose-adjusted AUC 0-24 values were within ±20% at all time points, postoperatively in the sleeve gastrectomy and oux-en-Y gastric bypass groups, with the largest changes occurring 1 month postoperatively (+14.5 and +17.2%, respectively). No statistically significant changes in any pharmacokinetic variables over time were reported; however, there was a trend toward increased maximum concentrations after surgery ( P = 0.069).

CONCLUSIONS

Our findings suggest that bariatric surgery has no systematic effect on the pharmacokinetics of escitalopram. However, because of the substantial interindividual variation, therapeutic drug monitoring can be considered to guide postoperative dose adjustments.

Escitalopram and Sertraline Population Pharmacokinetic Analysis in Pediatric Patients

BACKGROUND AND OBJECTIVE

Escitalopram and sertraline are commonly prescribed for anxiety and depressive disorders in children and adolescents. The pharmacokinetics (PK) of these medications have been evaluated in adults and demonstrate extensive variability, but studies in pediatric patients are limited. Therefore, we performed a population PK analysis for escitalopram and sertraline in children and adolescents to characterize the effects of demographic, clinical, and pharmacogenetic factors on drug exposure.

METHODS

A PK dataset was generated by extracting data from the electronic health record and opportunistic sampling of escitalopram- and sertraline-treated psychiatrically hospitalized pediatric patients aged 5-18 years. A population PK analysis of escitalopram and sertraline was performed using NONMEM. Concentration-time profiles were simulated using MwPharm++ to evaluate how covariates included in the final models influence medication exposure and compared to adult therapeutic reference ranges.

RESULTS

The final escitalopram cohort consisted of 315 samples from 288 patients, and the sertraline cohort consisted of 265 samples from 255 patients. A one-compartment model with a proportional residual error model best described the data for both medications. For escitalopram, CYP2C19 phenotype and concomitant CYP2C19 inhibitors affected apparent clearance (CL/F), and normalizing CL/F and apparent volume of distribution (V/F) to body surface area (BSA) improved estimations. The final escitalopram model estimated CL/F and V/F at 14.2 L/h/1.73 m2 and 428 L/1.73 m2, respectively. For sertraline, CYP2C19 phenotype and concomitant CYP2C19 inhibitors influenced CL/F, and empirical allometric scaling of patient body weight on CL/F and V/F was significant. The final sertraline model estimated CL/F and V/F at 124 L/h/70 kg and 4320 L/70 kg, respectively. Normalized trough concentrations (Ctrough) for CYP2C19 poor metabolizers taking escitalopram were 3.98-fold higher compared to normal metabolizers (151.1 ng/mL vs 38.0 ng/mL, p < 0.0001), and normalized Ctrough for CYP2C19 poor metabolizers taking sertraline were 3.23-fold higher compared to normal, rapid, and ultrarapid metabolizers combined (121.7 ng/mL vs 37.68 ng/mL, p < 0.0001). Escitalopram- and sertraline-treated poor metabolizers may benefit from a dose reduction of 50-75% and 25-50%, respectively, to normalize exposure to other phenotypes.

CONCLUSION

To our knowledge, this is the largest population PK analysis of escitalopram and sertraline in pediatric patients. Significant PK variability for both medications was observed and was largely explained by CYP2C19 phenotype. Slower CYP2C19 metabolizers taking escitalopram or sertraline may benefit from dose reductions given increased exposure.

Low Escitalopram Concentrations in Patients with Depression predict Treatment Failure: A Naturalistic Retrospective Study

INTRODUCTION

Cross sectional therapeutic drug monitoring (TDM) data mining introduces new opportunities for the investigation of medication treatment effects to find optimal therapeutic windows. Medication discontinuation has been proven useful as an objective surrogate marker to assess treatment failure. This study aimed to investigate the treatment effects of escitalopram and pharmacokinetic influences on blood levels using retrospectively assessed data from a TDM database.

METHODS

Data was collected from 134 patients longitudinally treated with escitalopram for whom TDM was requested to guide drug therapy. Escitalopram metabolism was estimated by the log-transformed dose-corrected concentrations and compared within subpopulations differing in age, gender, renal function, smoking status, body mass index, and comedication.

RESULTS

Patients with a depressive episode who were treated with escitalopram and discontinued the treatment within the hospital stay showed lower serum concentrations compared to patients who continued escitalopram treatment with a concentration of 15 ng/mL separating both groups. Variability was high between individuals and factors influencing blood levels, including dose, sex, and age. Comedication that inhibits cytochrome P450 (CYP) 2C19 isoenzymes were further found to influence escitalopram pharmacokinetics independent of dose, age or sex.

DISCUSSION

Medication switch is a valuable objective surrogate marker to assess treatment effects under real-world conditions. Of note, treatment discontinuation is not always a cause of insufficient response but may also be related to other factors such as medication side effects. TDM might not only be useful in addressing these issues but titrating drug concentrations into the currently recommended reference range for escitalopram will also increase response in non-responders and avoid treatment failure in underdosed patients.