Duloxetine: clinical pharmacokinetics and drug interactions

New drug combination regimen based on pharmacokinetic characteristics-Erdafitinib combined with sertraline or duloxetine

The aim of this study is to investigate novel strategies for reducing adverse reactions caused by erdafitinib through a drug combination based on its pharmacokinetic characteristics. The spectrum and characterizations of drugs that can inhibit the metabolism of erdafitinib are examined both in vitro and in vivo. The efficacy of combination regimens are then evaluated using subcutaneous xenograft tumor models. The results demonstrated that sertraline and duloxetine, out of more than 100 screened drugs, inhibited the metabolism of erdafitinib through mixed and non-competitive inhibition, respectively. This inhibition primarily occurred via the CYP2C9 and CYP2D6 pathways. The primary alleles of CYP2C9 and CYP2D6 not only determine the metabolic characteristics of erdafitinib but also influence the strength of drug-drug interactions. Co-administration of sertraline or duloxetine with erdafitinib in rats and mice resulted in nearly a three-fold increase in the blood exposure of erdafitinib and its major metabolite M6. When sertraline or duloxetine was combined with 1/3 of the erdafitinib dosage, the anti-proliferative and pro-apoptotic effects on SNU-16 xenografts were comparable to those of the original full dose of erdafitinib. However, the combination regimen significantly mitigated hyperphosphatemia, retinal damage, intestinal villus damage, and gut microbiome dysbiosis. This study utilized pharmacokinetic methods to propose a new formulation of erdafitinib combined with sertraline or duloxetine. The findings suggest that this combination has potential for clinical co-administration based on a database analysis, thereby providing a novel strategy for anti-tumor treatment with fibroblast growth factor receptor (FGFR) inhibitors.

Analgesic medication considerations for chronic pain management post-bariatric surgery

INTRODUCTION

Bariatric surgery, an option for obesity management, can significantly alter gastrointestinal structure and processes. These changes can impact the pharmacokinetics (PK) of medications, which can translate to clinical differences in efficacy and safety. Chronic pain is prevalent in obesity and often persists post-bariatric surgery.

AREAS COVERED

This narrative review examines the PubMed literature from 1990 to January 2024 for the impact of bariatric surgery on the management of chronic pain medications including non-opioid (acetaminophen, non-steroidal anti-inflammatory drugs, antidepressants, and cannabinoids) and opioid medications.

EXPERT OPINION

An individualized medication management approach is ideal for post-bariatric surgery patients, as PK parameters, type of surgery, time since surgery, and patient-specific factors make it difficult to support blanket recommendations. Close monitoring of efficacy and safety outcomes is essential in chronic pain management. While the PK of acetaminophen and opioids are impacted, the value of these medications in the setting of chronic pain is dwindling as more efficacy and safety data emerges. A life-long ban of NSAIDs due to marginal ulcer risk is not endorsed; rather, we advocate for shifting the focus to marginal ulcer prevention strategies, individualized benefit-risk analysis, and safety monitoring using surrogate markers.

Duloxetine enhances PAX6 expression and suppresses innate immune responses in murine LPS-induced corneal inflammation

BACKGROUND-AIM

PAX6 is a key regulator of eye development and epithelial homeostasis in the cornea. When deficient, chronic corneal inflammation, neovascularization and limbal stem cell deficiency can occur. Here we investigated the potential of duloxetine, a generic serotonin reuptake inhibitor that can upregulate PAX6 in vitro, for its in vivo activity in the context of corneal inflammation.

METHODS

Duloxetine tolerance was tested in a human limbal stem cell line and isogenic CRISPR-knockout PAX6+/- cells. C57BL/6-Wildtype mice were administered duloxetine eye drops at concentrations of 1 μM - 2 mM and tested for toxicity and corneal PAX6 expression. In LPS-induced corneal inflammation in mice, duloxetine's effect on PAX6 expression, corneal opacification and inflammatory responses were evaluated by in vivo corneal imaging, immunostaining, and whole-transcriptome microarray analysis.

RESULTS

No toxicity was observed in vitro for duloxetine concentrations up to 10μΜ. In vivo, duloxetine drops were well-tolerated up to 50 μM. Duloxetine drops at 10μΜ significantly upregulated PAX6 protein levels in the cornea by 30 % within 2 days. In the LPS model, duloxetine resulted in a sustained 33 % PAX6 protein upregulation in the cornea at 7 days, and in reduced opacity within 2 days, accompanied by a significant dampening of IL-17A signaling, neutrophil degranulation, microglial activation, macrophage markers, and MMP expression, despite non-significant changes in total inflammatory cell infiltration.

CONCLUSION

Short-term administration of a repurposed generic drug, duloxetine, upregulates PAX6 protein levels in the cornea of mice and exerts an anti-inflammatory activity by dampening innate immune responses.

Interactions of antidepressants with concomitant medications-safety of complex therapies in multimorbidities

Depression is the fourth most serious disease in the world. Left untreated, it is a cause of suicide attempts, emergence or exacerbation worsening of serious diseases, bodily and mental disorders, as well as increased risk of cardiovascular diseases, stroke, diabetes, and obesity, as well as endocrine and neurological diseases. Frequent coexistence of depression and other diseases requires the simultaneous use of several drugs from different therapeutic groups, which very often interact and intensify comorbidities, sometimes unrelated mechanisms. Sufficient awareness of potential drug interactions is critical in clinical practice, as it allows both to avoid disruption of proper pharmacotherapy and achieve substantive results. Therefore, this review aims to analyze the interactions of antidepressants with other concomitant medications. Against the backdrop of experimental research and a thorough analysis of the up-to-date literature, the authors discuss in detail the mechanisms and effects of action of individual drug interactions and adaptogens, including the latest antidepressants.

Effectiveness of Duloxetine versus Other Therapeutic Modalities in Patients with Diabetic Neuropathic Pain: A Systematic Review and Meta-Analysis

Objectives: Diabetic peripheral neuropathy (DPN) is a chronic complication of diabetes mellitus (DM) with symptoms like intense pain and impaired quality of life. This condition has no treatment; instead, the pain is managed with various antidepressants, including duloxetine. The aim of this study is to analyze the evidence on the efficacy of duloxetine in the management of DPN. Methods: A systematic search in different databases was conducted using the keywords "diabetic neuropathy", "duloxetine therapy", "neuropathic pain", and "Diabetes Mellitus". Finally, eight studies were included in this meta-analysis. Results: All articles comparing duloxetine at different doses vs. a placebo reported significant differences in favor of duloxetine on pain scales like 24 h Average Pain Severity (standardized mean difference [SMD] = -1.06, confidence interval [CI] = -1.09 to -1.03, and p < 0.00001) and BPI Severity (SMD = -0.70, CI = -0.72 to -0.68, and p < 0.00001), among others. A total of 75% of the meta-analyses of studies comparing duloxetine at different doses showed a tendency in favor of the 120 mg/d dose. There were significant differences in favor of duloxetine when compared to routine care on the Euro Quality of Life (SMD = -0.04, CI = -0.04 to -0.03, and p < 0.00001) and SF-36 Survey (SMD = -5.86, CI = -6.28 to -5.44, and p < 0.00001) scales. There were no significant differences on the visual analog scale (VAS) when comparing duloxetine and gabapentin. Conclusions: Duloxetine appears to be effective in the management of DPN in different pain, symptom improvement, and quality of life scales.

Sex-Gender Differences Are Completely Neglected in Treatments for Neuropathic Pain

As sex-gender differences have been described in the responses of patients to certain medications, we hypothesized that the responses to medications recommended for neuropathic pain may differ between men and women. We conducted a literature review to identify articles reporting potential sex-gender differences in the efficacy and safety of these medications. Only a limited number of studies investigated potential sex-gender differences. Our results show that women seem to achieve higher blood concentrations than men during treatment with amitriptyline, nortriptyline, duloxetine, venlafaxine, and pregabalin. Compared to men, higher rates of women develop side effects during treatment with gabapentin, lidocaine, and tramadol. Globally, the sex-gender differences would suggest initially administering smaller doses of these medications to women with neuropathic pain compared to those administered to men. However, most of these differences have been revealed by studies focused on the treatment of other diseases (e.g., depression). Studies focused on neuropathic pain have overlooked potential sex-gender differences in patient responses to medications. Despite the fact that up to 60% of patients with neuropathic pain fail to achieve an adequate response to medications, the potential role of sex-gender differences in the efficacy and safety of pharmacotherapy has not adequately been investigated. Targeted studies should be implemented to facilitate personalized treatments for neuropathic pain.

Caution for psychiatrists: malignant hyperthermia risks with the anesthetic agent succinylcholine (Suxamethonium) during electroconvulsive therapy

BACKGROUND

Malignant hyperthermia is a potentially lethal condition triggered by specific anesthetic drugs, especially a depolarizing muscle relaxant of succinylcholine (Suxamethonium). Despite the frequent use of succinylcholine with electroconvulsive therapy (ECT), there has been no reported case of potentially lethal malignant hyperthermia following ECT. In addition, the time interval between the administration of succinylcholine and the onset of malignant hyperthermia has not been outlined in the context of ECT.

CASE PRESENTATION

We present the case of a 79-year-old woman suffering from severe depression, who experienced severe malignant hyperthermia due to succinylcholine administration during an ECT session. She presented with a high fever of 40.2 °C, tachycardia of 140/min, hypertension with a blood pressure exceeding 200 mmHg, significant muscle rigidity, and impaired consciousness. These symptoms emerged two hours after ECT, which occurred in a psychiatric ward rather than an operating room, and reached their peak in less than 24 h. She was given 60 mg of dantrolene, which quickly reduced the muscular rigidity. Subsequently, she received two additional doses of 20 mg and 60 mg of dantrolene, which brought her fever down to 36.2 °C and completely eased her muscle rigidity within two days after ECT.

CONCLUSIONS

This is the first reported case of potentially lethal malignant hyperthermia after ECT. In addition, it highlights the delayed onset of malignant hyperthermia following an ECT procedure, emphasizing the necessity for psychiatrists to recognize its onset even after the treatment. In the light of potentially lethal consequences of malignant hyperthermia, it is critically important for psychiatrists to closely monitor both intraoperative and postoperative patient's vital signs and characteristic physical presentations, promptly identify any symptomatic emergence, and treat it immediately with dantrolene.

Ageing-related considerations for medication used in supportive care in cancer

Both randomized controlled trials (RCTs) and retrospective studies have shown that a comprehensive geriatric assessment (CGA) prior to a patient commencing systemic anti-cancer therapy (SACT) results in improved quality of life outcomes and is associated with a decreased risk of grade 3-5 toxicity; however, data are lacking in relation to adverse drug events (ADE) associated with supportive care medications. Supportive care medications are prescribed as prophylactic agents in a SACT regimen, for management of treatment related toxicity and for symptoms caused by the disease itself. While necessary, the commencement of SACT and supportive medications may cause, or exacerbate, a significant drug burden in older patients, some of whom may have existing comorbidities. For many medications, older adults are underrepresented in pharmacokinetic and pharmacodynamic modelling studies. In this article we will review ageing-related changes in pharmacokinetics and pharmacodynamics, as well as how these changes may impact supportive care medications. Additional considerations for prescribing these medications in older adults with cancer, such as polypharmacy, potentially inappropriate medications, drug-drug interactions, and anticholinergic burden, as well as ageing-related considerations and recommendations for supportive care medications commonly used in older adults with cancer are also reviewed.

Pharmacotherapy for osteoarthritis-related pain: current and emerging therapies

INTRODUCTION

Osteoarthritis (OA) related pain has affected millions of people worldwide. However, the current pharmacological options for managing OA-related pain have not achieved a satisfactory effect.

AREAS COVERED

This narrative review provides an overview of the current and emerging drugs for OA-related pain. It covers the drugs' mechanism of action, safety, efficacy, and limitations. The National Library of Medicine (PubMed) database was primarily searched from 2000 to 2024.

EXPERT OPINION

Current treatment options are limited and suboptimal for OA pain management. Topical nonsteroidal anti-inflammatory drugs (NSAIDs) are the recognized and first-line treatment in the management of OA-related pain, and other drugs are inconsistent recommendations by guidelines. Emerging treatment options are promising for OA-related pain, including nerve growth factor (NGF) inhibitors, ion channel inhibitors, and calcitonin gene-related peptide (CGRP) antagonists. Besides, drugs repurposing from antidepressants and antiepileptic analgesics are shedding light on the management of OA-related pain. The management of OA-related pain is challenging as pain is heterogeneous and subjective. A more comprehensive strategy combined with non-pharmacological therapy needs to be considered, and tailored management options to individualized patients.

Comparison of Protective Effects of Antidepressants Mediated by Serotonin Receptor in Aβ-Oligomer-Induced Neurotoxicity

Amyloid β-peptide (Aβ) synthesis and deposition are the primary factors underlying the pathophysiology of Alzheimer's disease (AD). Aβ oligomer (Aβo) exerts its neurotoxic effects by inducing oxidative stress and lesions by adhering to cellular membranes. Though several antidepressants have been investigated as neuroprotective agents in AD, a detailed comparison of their neuroprotection against Aβo-induced neurotoxicity is lacking. Here, we aimed to elucidate the neuroprotective effects of clinically prescribed selective serotonin reuptake inhibitors, serotonin-norepinephrine reuptake inhibitors, and noradrenergic and specific serotonergic antidepressants at the cellular level and establish the underlying mechanisms for their potential clinical applications. Therefore, we compared the neuroprotective effects of three antidepressants, fluoxetine (Flx), duloxetine (Dlx), and mirtazapine (Mir), by their ability to prevent oxidative stress-induced cell damage, using SH-SY5Y cells, by evaluating cell viability, generation of reactive oxygen species (ROS) and mitochondrial ROS, and peroxidation of cell membrane phospholipids. These antidepressants exhibited potent antioxidant activity (Dlx > Mir > Flx) and improved cell viability. Furthermore, pretreatment with a 5-hydroxytryptamine 1A (5-HT1A) antagonist suppressed their effects, suggesting that the 5-HT1A receptor is involved in the antioxidant mechanism of the antidepressants' neuroprotection. These findings suggest the beneficial effects of antidepressant treatment in AD through the prevention of Aβ-induced oxidative stress.

Utilizing Pharmacogenomics Results to Guide Antidepressant Selection: A Case Report

The case discussion demonstrates the benefit of using Pharmacogenomic (PGx) results to aid in the selection of antidepressant therapy and improve response to treatment. Nearly half of patients diagnosed with major depressive disorder fail initial therapy and may require multiple trials of antidepressants. Genetic variation in several metabolic enzymes contribute to the variable response to antidepressant therapy. PGx testing provides an opportunity to inform antidepressant selection and optimize therapeutic outcomes, while minimizing risk of adverse events. A 79-year-old female who had been experiencing a suboptimal response to escitalopram following dose escalation over a period of three years was referred for a PGx consultation. A clinical pharmacist assessed significant drug-gene, drug-drug, and drug-drug-gene interactions, and relevant clinical information to recommend alternative antidepressant therapy, which resulted in mood improvement.

Duloxetine reduces opioid consumption and pain after total hip or knee arthroplasty: a meta-analysis of randomized controlled trials

PURPOSE

There is no consensus in the current literature on the analgesic role of duloxetine after total hip arthroplasty (THA) or total knee arthroplasty (TKA). Thus, we designed this meta-analysis to reveal the analgesic effectiveness and safety of duloxetine in TKA or THA.

METHODS

As of October 2022, two authors (L.C. and W.Q.J.) independently searched five main databases (EMBASE, Web of Science, PubMed, Cochrane Library, and Google Scholar) to find relevant studies. Duloxetine vs. placebo in randomized controlled trials (RCTs) for THA or TKA were included. We set perioperative total opioid consumption as the primary outcome. Secondary outcomes included resting or dynamic pain scores over time, gastrointestinal adverse events, neurological adverse events, and other adverse reactions.

RESULTS

Eight RCTs with 695 patients were incorporated in our study. This meta-analysis showed high evidence that duloxetine was effective in reducing perioperative opioid consumption (Standard mean difference [SMD] = - 0.50, 95% confidence intervals [CI]: -0.70 to - 0.31, P < 0.00001) and low to moderate evidence that duloxetine could reduce pain within three weeks after surgery. Low to high evidence showed no differences between the two groups for most adverse events. Substantial evidence suggests that duloxetine can reduce nausea and vomiting after surgery (Risk ratio [RR] = 0.69, 95% CI: 0.50 to 0.95, P = 0.02, I2 = 4%). However, moderate evidence suggested that duloxetine might be associated with increased postoperative drowsiness (RR = 1.83, 95% CI: 1.08 to 3.09, P = 0.02, I2 = 0%).

CONCLUSION

Duloxetine reduced overall opioid consumption in the perioperative period and relieved pain within three weeks after surgery without increasing the risk of adverse drug events. Duloxetine can be part of a multimodal management regimen in patients with THA and TKA.

Management of anhedonia after epilepsy surgery

Anhedonia is clinically defined as difficulty or inability to feel pleasure or to be motivated to perform activities that were previously pleasurable. Anhedonia is a core feature of depressive disorders but can be present in other conditions such as substance use and anxiety disorders. Herein we report the case of a 34-year-old female who developed marked anhedonia after left cortico-amygdalohippocampectomy. Despite optimal seizure control, the person struggled with anhedonia and other depressive symptoms. After ruling out medico-neurologic complications, she was prescribed with a selective serotonin reuptake inhibitor and cognitive-behavioral therapy. Anhedonia can be a challenging neuropsychiatric presentation that requires ruling out the effects of antiseizure medications, neurosurgery, and other drugs before prescribing antidepressants.

The effect of duloxetine on postoperative pain and opium consumption in spine surgery: A systematic review

Background

Postoperative pain after spinal surgery is a major problem that can impact patients' quality of life. Duloxetine is a serotonin and norepinephrine reuptake inhibitor (SNRI) with analgesic effect in different pain disorders. In this study, we aim to evaluate the safety and analgesic effect of duloxetine on acute and chronic pain following spine surgery.

Methods

A systematic search was completed on MEDLINE, PsycINFO, and Embase through OVID from inception to April 2023 to find relevant articles. We used Cochrane methodology to evaluate the bias of included studies. Investigated outcomes included postoperative pain, opioid consumption, and adverse events.

Results

Seven articles involving 487 participants were included in our systematic review. Out of 7 papers, 5 were randomized clinical trials, 1 was a pilot trial and 1 was a retrospective observational study. The results of these studies indicated the analgesic effect of duloxetine on postoperative pain, which was measured using numeric rating scale, verbal numeric scale, brief pain inventory, and visual analogue scale. Duloxetine was generally safe without serious adverse events. The most common reported adverse events included headache, nausea, vomiting, itching, dizziness, and drowsiness.

Conclusions

Duloxetine may be an effective treatment option for postoperative pain following spine surgery, but further rigorously designed and well-controlled randomized trials are required.

Does sex affect the efficacy of systemic pharmacological treatments of pain in knee osteoarthritis? A systematic review

Objective

To determine whether sex influences the analgesic efficacy of systemic pharmacological treatment in patients with knee osteoarthritis.

Design

A systematic review, guided by Cochrane methods, sourced studies from Medline, Cochrane Library, Embase, and CINAHL Plus with Full Text as of October 10, 2022. Eligible studies were double-blind RCTs evaluating systemic pharmacological treatments for knee osteoarthritis in adults, with minimum 30-day treatment duration, reporting sex-specific results or mentioning sex subgroup analysis for analgesic efficacy. The risk of bias was assessed using the Cochrane Risk of Bias tool version 2 (RoB 2).

Results

9 studies (5201 participants) met inclusion criteria, analyzing drugs including duloxetine, etoricoxib, tapentadol, naproxcinod, lutikizumab, and rofecoxib. Only one study reported sex-specific results. Review findings suggested no significant sex-based differences in treatment efficacy, however, data were limited due to a lack of sex-specific reporting or inclusion of sex in subgroup analyses.

Conclusions

Current evidence does not support the existence of sex differences in the analgesic efficacy of systemic knee osteoarthritis treatments. However, this conclusion is substantially limited by the paucity of sex-specific reporting of results or subgroup analyses in most primary studies, emphasizing the need for future research to report on sex-stratified data to allow for comprehensive, personalized treatment strategies.

Addressing Ancestry and Sex Bias in Pharmacogenomics

The association of an individual's genetic makeup with their response to drugs is referred to as pharmacogenomics. By understanding the relationship between genetic variants and drug efficacy or toxicity, we are able to optimize pharmacological therapy according to an individual's genotype. Pharmacogenomics research has historically suffered from bias and underrepresentation of people from certain ancestry groups and of the female sex. These biases can arise from factors such as drugs and indications studied, selection of study participants, and methods used to collect and analyze data. To examine the representation of biogeographical populations in pharmacogenomic data sets, we describe individuals involved in gene-drug response studies from PharmGKB, a leading repository of drug-gene annotations, and showcaseCYP2D6, a gene that metabolizes approximately 25% of all prescribed drugs. We also show how the historical underrepresentation of females in clinical trials has led to significantly more adverse drug reactions in females than in males.

The Impact of the CYP2D6 and CYP1A2 Gene Polymorphisms on Response to Duloxetine in Patients with Major Depression

Depression is a global mental health concern, and personalized treatment approaches are needed to optimize its management. This study aimed to investigate the influence of the CYP2D6 and CYP1A2 gene polymorphisms on the efficacy of duloxetine in reducing depressive and anxiety symptoms. A sample of 100 outpatients with major depression, who initiated monotherapy with duloxetine, were followed up. Polymorphisms in the CYP2D6 and CYP1A2 genes were assessed. The severity of depressive and anxiety symptoms was recorded using standardized scales. Adverse drug reactions (ADRs) were analyzed. Statistical analyses, including linear regression, were conducted to examine the relationships between genetic polymorphisms, clinical variables, and treatment outcomes. Patients with higher values of the duloxetine metabolic index (DMI) for CYP2D6, indicating a faster metabolism, achieved a greater reduction in anxiety symptoms. The occurrence of ADRs was associated with a lower reduction in anxiety symptoms. However, no significant associations were found between studied gene polymorphisms and reduction in depressive symptoms. No significant effects of the DMI for CYP1A2 were found. Patients with a slower metabolism may experience less benefit from duloxetine therapy in terms of anxiety symptom reduction. Personalizing treatment based on the CYP2D6 and CYP1A2 gene polymorphisms can enhance the effectiveness of antidepressant therapy and improve patient outcomes.

Psychopharmacology of smoking cessation medications: focus on patients with mental health disorders

The adverse effects of smoking cessation in individuals with mental health disorders have been a point of concern, and progress in the development of treatment has been slow. The primary first-line treatments for smoking cessation are Nicotine Replacement Therapy, Bupropion, Varenicline, and behavioural support. Nortriptyline and Clonidine are second-line treatments used when the first-line treatments are not effective or are contraindicated. Smoking cessation medications have been shown to be effective in reducing nicotine cravings and withdrawal symptoms and promoting smoking cessation among patients living with mental disorders. However, these medications may have implications for patients' mental health and need to be monitored closely. The efficacy and side effects of these medications may vary depending on the patient's psychiatric condition, medication regimen, substance use, or medical comorbidities. The purpose of this review is to synthesise the pharmacokinetics, pharmacodynamics, therapeutic effects, adverse effects, and pharmacological interactions of first- and second-line smoking cessation drugs, with an emphasis on patients suffering from mental illnesses. Careful consideration of the risks and benefits of using smoking cessation medications is necessary, and treatment plans must be tailored to individual patients' needs. Monitoring symptoms and medication regimens is essential to ensure optimal treatment outcomes.

Serotonin Syndrome From Duloxetine Monotherapy: A Case Report

Serotonin syndrome is a rare adverse reaction induced by serotonergic drugs. Most instances of the syndrome occur in the context of a serotonergic drug overdose and the combined use of monoamine oxidase inhibitors and other related drugs. We report a case of serotonin syndrome caused by duloxetine alone in an elderly Asian woman and review the literature. A 69-year-old woman was admitted to the hospital due to two months of irritability and reduced energy. She was diagnosed with depressive disorder in the outpatient department and took sertraline 75mg for one month, but there was no significant improvement of symptoms. After admission, sertraline was switched to duloxetine. After taking duloxetine 60mg, the patient developed confusion, inducible clonus, diaphoresis, tremor, hyperreflexia, and increased body temperature and blood pressure. Reviewing her history of drug exposure, physical examination, and associated laboratory tests, we ruled out other possible diseases and established a serotonin syndrome diagnosis. The symptoms and signs associated with serotonin syndrome disappeared within two days after treatments with hydration and diazepam and the withdrawal of duloxetine. Physicians should be watchful for serotonin syndrome, a rare, but in severe cases life-threatening, adverse drug reaction. It may occur with duloxetine monotherapy even at therapeutic doses.

Pharmaceutical treatment of osteoarthritis

OBJECTIVE

To review the current state of pharmaceutical treatment recommendations for the management of osteoarthritis.

METHOD

A narrative review was drafted to describe treatment guidelines, mechanism of action, pharmacokinetics, and toxicity for nine classes of pharmaceuticals: 1) oral nonsteroidal anti-inflammatory drugs (NSAIDs), 2) topical NSAIDs, 3) COX-2 inhibitors, 4) duloxetine, 5) intra-articular corticosteroids, 6) intra-articular hyaluronic acid, 7) acetaminophen (paracetamol), 8) tramadol, and 9) capsaicin.

RESULTS

In general, oral and topical NSAIDs, including COX-2 inhibitors, are strongly recommended first-line treatments for osteoarthritis due to their ability to improve pain and function but are associated with increased risks in patients with certain comorbidities (e.g., heightened cardiovascular risks). Intra-articular corticosteroid injections are generally recommended for osteoarthritis management and have relatively minor adverse effects. Other treatments, such as capsaicin, tramadol, and acetaminophen, are more controversial, and many updated guidelines offer differing recommendations.

CONCLUSION

The pharmaceutical management of osteoarthritis is a constantly evolving field. Promising treatments are emerging, and medicines that were once considered conventional (e.g., acetaminophen) are gradually becoming less acceptable based on concerns with efficacy and safety. Clinicians need to consider the latest evidence and recommendations to make an informed decision with their patients about how to optimize treatment plans for patients with knee, hip, polyarticular, or hand osteoarthritis.

Pharmacogenetics in the Treatment of Huntington’s Disease: Review and Future Perspectives

Huntington’s disease (HD) is an autosomal dominant progressive brain disorder, caused by a pathological expansion of a CAG repeat that encodes the huntingtin gene. This genetic neurodegenerative rare disease is characterized by cognitive, motor, and neuropsychiatric manifestations. The aim of the treatment is symptomatic and addresses the hyperkinetic disorders (chorea, dystonia, myoclonus, tics, etc.) and the behavioural and cognitive disturbances (depression, anxiety, psychosis, etc.) associated with the disease. HD is still a complex condition in need of innovative and efficient treatment. The long-term goal of pharmacogenetic studies is to use genotype data to predict the effective treatment response to a specific drug and, in turn, prevent potential undesirable effects of its administration. Chorea, depression, and psychotic symptoms have a substantial impact on HD patients’ quality of life and could be better controlled with the help of pharmacogenetic knowledge. We aimed to carry out a review of the available publications and evidence related to the pharmacogenetics of HD, with the objective of compiling all information that may be useful in optimizing drug administration. The impact of pharmacogenetic information on the response to antidepressants and antipsychotics is well documented in psychiatric patients, but this approach has not been investigated in HD patients. Future research should address several issues to ensure that pharmacogenetic clinical use is appropriately supported, feasible, and applicable.

The roles of Cyp1a2 and Cyp2d in pharmacokinetic profiles of serotonin and norepinephrine reuptake inhibitor duloxetine and its metabolites in mice

Duloxetine (DLX) is widely used to treat major depressive disorder. Little is known about the mechanistic basis for DLX-related adverse effects (e.g., liver injury). Human CYP1A2 and CYP2D6 mainly contributes to DLX metabolism, which was proposed to be involved in its adverse effects. Here, we investigated the roles of Cyp1a2 and Cyp2d on DLX pharmacokinetic profile and tissue distribution using a Cyp1a2 knockout (Cyp1a2-KO) mouse model together with a Cyp2d inhibitor (propranolol). Cyp1a2-KO has the few effects on the systematic exposure (area under the plasma concentration-time curve, AUC) and tissue disposition of DLX and its primary metabolites. Propranolol dramatically increased the AUCs of DLX by 3 folds and 1.5 folds in WT and Cyp1a2-KO mice, respectively. Meanwhile, Cyp2d inhibitor decreased the AUC of Cyp2d-involved DLX metabolites (e.g., M16). Mouse tissue distribution revealed that DLX and its major metabolites were the most abundant in kidney, followed by liver and lung with/without Cyp2d inhibitor. Cyp2d inhibitor significantly increased DLX levels in tissues (e.g., liver) in WT and KO mice and decreases the levels of M3, M15, M16 and M17, while it increased the levels of M4, M28 and M29 in tissues. Our findings indicated that Cyp2d play a fundamental role on DLX pharmacokinetic profile and tissue distribution in mice. Clinical studies suggested that CYP1A2 has more effects on DLX systemic exposure than CYP2D6. Further studies in liver humanized mice or clinical studies concerning CYP2D6 inhibitors-DLX interaction study could clarify the roles of CYP2D6 on DLX pharmacokinetics and toxicity in human.

Evaluation of the effects of duloxetine treatment on anterior segment parameters by optical coherence tomography

PURPOSE

To evaluate the effects of Duloxetine on anterior segment parameters and intraocular pressure (IOP) in open angle eyes.

METHODS

38 eyes of 38 patients with fibromyalgia who had open or wide open angles according to the Shaffer classification. Anterior segment optic coherence tomography was performed before and after (month 3) Duloxetine treatment. IOP, central corneal thickness (CCT), corneal endothelial cell density (CECD) and anterior chamber depth (ACD) were also recorded and evaluated.

RESULTS

No statistically significant difference was determined in IOP, CCT and CECD (p > 0.05). However, a statistically significant decrease was determined in both the temporal and nasal anterior chamber angle, angle opening distance, nasal trabecular-iris space area and ACD values between the baseline and month 3 (p < 0.001).

DISCUSSION

We think that the short term use of Duloxetine does not lead to clinically significant changes despite their statistically significant effects on the anterior chamber parameters.

[Comparative analysis of the use of symptomatic slow acting drugs for osteoarthritis containing chondroitin sulfate or affecting its biosynthesis in patients with non-specific low back pain]

OBJECTIVE

Retrospective comparative analysis of the use of SYSADOA preparations containing chondroitin sulfate (Chondroguard, 2 ml, 25 amp., glycosaminoglycan-peptide complex, 1 ml 25 amp., bioactive concentrate of small marine fish, 2 ml, 10 amp.) in patients with chronic non-specific low back pain (LBP) of lumbar and sacral localization caused by spondylosis and osteochondrosis of the lumbar spine, at the stage of outpatient care.

MATERIAL AND METHODS

Data of medical records of patients (n=120; men - 32, women - 88, age - 54.1±7.6 years, duration of disease exacerbation 4.0±1.7 months) with nonspecific LBP were systematized according to the inclusion/exclusion criteria. All patients were divided into 4 groups: Group 1 (n=30) received Chondroguard im., 2 ml every other day, the course of treatment was 25 injections, 25 days; Group 2 (n=30) received glycosaminoglycan-peptide complex on the 1st day - 0.3 ml, on the 2nd day - 0.5 ml, and then 3 times a week for 1 ml, course of treatment - 25 injections, 25 days; Group 3 (n=30) received bioactive concentrate of small marine fish, 2 ml im., every other day, the course of treatment was 10 injections; repeated courses of treatment - after 6 months; Group 4 (n=30) received Amelotex (meloxicam) at a dose of 15 mg once a day for 15 days. All patients of the first 3 groups received Amelotex at a dose of 15 mg with the possibility of reducing the dose to 7.5 mg or completely discontinuing the drug if necessary. Retrospectively, dynamic monitoring was performed in the medical records of outpatients after 50 days and 6 months from the start of therapy according to the following parameters: intensity of pain according to VAS, short form of the McGill pain questionnaire, vital signs of patients (Oswestry Disability Index, version 2.1a [Oswestry Disability Index], and Roland-Morris questionnaire), propensity to chronic pain syndrome according to the STarT Back Screening Tool questionnaire, the presence and severity of comorbid fibromyalgia according to the Fibromyalgia Rapid Screening Tool questionnaire, the level of pain catastrophization according to the Pain Catastrophizing Scale, the severity of comorbid anxiety and depression according to the Hospital Anxiety and Depression Scale, the severity comorbid insomnia (Insomnia Severity Index), quality of life according to the SF-36 scale, the effectiveness of drugs according to the patient on a 5-point scale, the need to take NSAIDs and analgesics, tolerability on a 4-point system. The safety of therapy was monitored using the WHO and Naranjo scales.

RESULTS

In patients with nonspecific LBP, a greater degree of reduction in the intensity of the pain syndrome, a smaller number of exacerbations of the pain syndrome over 6 months of observation, an improvement in the functional status and life activity, a tendency to a decrease in the severity of anxiety and depression, sleep disturbances and comorbid fibromyalgia, limiting the risk of chronicity and catastrophization of pain, the presence of a structure-modifying effect on IVD and degenerative changes in the facet joints, a significant improvement in the physical and mental components of health, high satisfaction and safety of therapy, which included taking Chondroguard with meloxicam, with a decrease in the need to take the latter by the 50th day observation period compared to other regimens. The effects of Chondroguard and meloxicam turned out to be long-term and were recorded by the 6th month in the absence of Chondroguard, which indicated the preservation of the influence of highly purified cholesterol on the pathogenetic mechanisms of the formation of LBP.

CONCLUSION

The study allows us to recommend the use of a parenteral form of cholesterol (Chondroguard, CJSC «PharmFirma «Sotex», Russia) for the treatment of nonspecific LBP with moderate or severe pain, chronic relapsing or persistent course, in combination with NSAIDs and their subsequent cancellation or administration on demand.

Predicting disruptions to drug pharmacokinetics and the risk of adverse drug reactions in non-alcoholic steatohepatitis patients

The liver plays a central role in the pharmacokinetics of drugs through drug metabolizing enzymes and transporters. Non-alcoholic steatohepatitis (NASH) causes disease-specific alterations to the absorption, distribution, metabolism, and excretion (ADME) processes, including a decrease in protein expression of basolateral uptake transporters, an increase in efflux transporters, and modifications to enzyme activity. This can result in increased drug exposure and adverse drug reactions (ADRs). Our goal was to predict drugs that pose increased risks for ADRs in NASH patients. Bibliographic research identified 71 drugs with reported ADRs in patients with liver disease, mainly non-alcoholic fatty liver disease (NAFLD), 54 of which are known substrates of transporters and/or metabolizing enzymes. Since NASH is the progressive form of NAFLD but is most frequently undiagnosed, we identified other drugs at risk based on NASH-specific alterations to ADME processes. Here, we present another list of 71 drugs at risk of pharmacokinetic disruption in NASH, based on their transport and/or metabolism processes. It encompasses drugs from various pharmacological classes for which ADRs may occur when used in NASH patients, especially when eliminated through multiple pathways altered by the disease. Therefore, these results may inform clinicians regarding the selection of drugs for use in NASH patients.

Precision Medicine in Antidepressants Treatment

Precision medicine uses innovative approaches to improve disease prevention and treatment outcomes by taking into account people's genetic backgrounds, environments, and lifestyles. Treatment of depression is particularly challenging, given that 30-50% of patients do not respond adequately to antidepressants, while those who respond may experience unpleasant adverse drug reactions (ADRs) that decrease their quality of life and compliance. This chapter aims to present the available scientific data that focus on the impact of genetic variants on the efficacy and toxicity of antidepressants. We compiled data from candidate gene and genome-wide association studies that investigated associations between pharmacodynamic and pharmacokinetic genes and response to antidepressants regarding symptom improvement and ADRs. We also summarized the existing pharmacogenetic-based treatment guidelines for antidepressants, used to guide the selection of the right antidepressant and its dose based on the patient's genetic profile, aiming to achieve maximum efficacy and minimum toxicity. Finally, we reviewed the clinical implementation of pharmacogenomics studies focusing on patients on antidepressants. The available data demonstrate that precision medicine can increase the efficacy of antidepressants and reduce the occurrence of ADRs and ultimately improve patients' quality of life.

Treatment for chemotherapy-induced peripheral neuropathy: A systematic review of randomized control trials

Purpose: Treatment of chemotherapy-induced peripheral neuropathy (CIPN) is challenging for clinicians, and many clinical trials and meta-analyses on CIPN are controversial. There are also few comparisons of the efficacy among drugs used to treat CIPN. Therefore, this systematic review aimed to study the efficacy of drugs in treating CIPN using existing randomized controlled trials. Methods: Electronic databases were searched for randomized controlled trials (RCTs) involving any pharmaceutical intervention and/or combination therapy of treating CIPN. Results: Seventeen RCTs investigating 16 drug categories, duloxetine, pregabalin, crocin, tetrodotoxin, venlafaxine, monosialotetrahexosyl ganglioside (GM1), lamotrigine, KA (ketamine and amitriptyline) cream, nortriptyline, amitriptyline, topical Citrullus colocynthis (bitter apple) oil, BAK (baclofen, amitriptyline hydrochloride, and ketamine) pluronic lecithin organogel, gabapentin, and acetyl l-carnitine (ALC), in the treatment of CIPN were retrieved. Many of the included RCTs consisted of small sample sizes and short follow-up periods. It was difficult to quantify due to the highly variable nature of outcome indicators. Conclusion: Duloxetine, venlafaxine, pregabalin, crocin, tetrodotoxin, and monosialotetrahexosyl ganglioside exhibited some beneficial effects in treating CIPN. Duloxetine, GM1, and crocin showed moderate benefits based on the evidence review, while lamotrigine, KA cream, nortriptyline, amitriptyline, and topical Citrullus colocynthis (bitter apple) oil were not beneficial. Further studies were necessary to confirm the efficacy of gabapentin in the treatment of CIPN because of the controversy of efficacy of gabapentin. Furthermore, BAK topicalcompound analgesic gel only had a tendency to improve the CIPN symptoms, but the difference was not statistically significant. ALC might result in worsening CIPN. Most studies were not of good quality because of small sample sizes. Therefore, standardized randomized controlled trials with large samples were needed to critically assess the effectiveness of these drugs in treating CIPN in the future.

Strategies for Assessing Acceptable Intakes for Novel N-Nitrosamines Derived from Active Pharmaceutical Ingredients

The detection of N-nitrosamines, derived from solvents and reagents and, on occasion, the active pharmaceutical ingredient (API) at higher than acceptable levels in drug products, has led regulators to request a detailed review for their presence in all medicinal products. In the absence of rodent carcinogenicity data for novel N-nitrosamines derived from amine-containing APIs, a conservative class limit of 18 ng/day (based on the most carcinogenic N-nitrosamines) or the derivation of acceptable intakes (AIs) using structurally related surrogates with robust rodent carcinogenicity data is recommended. The guidance has implications for the pharmaceutical industry given the vast number of marketed amine-containing drugs. In this perspective, the rate-limiting step in N-nitrosamine carcinogenicity, involving cytochrome P450-mediated α-carbon hydroxylation to yield DNA-reactive diazonium or carbonium ion intermediates, is discussed with reference to the selection of read-across analogs to derive AIs. Risk-mitigation strategies for managing putative N-nitrosamines in the preclinical discovery setting are also presented.

Determination of Patient Adherence for Duloxetine in Urine

Duloxetine, known by its brand name, CymbaltaTM, is a selective serotonin and norepinephrine reuptake inhibitor used to treat major depressive disorders. Determination of patient compliance for duloxetine is typically determined through medication possession ratio (MPR) or plasma concentrations. The purpose of this paper was to characterize normal urinary duloxetine concentrations in patients prescribed duloxetine to monitor patient adherence. Patient data collected from routine screens for duloxetine concentrations in urine were included in this study. Inclusion criteria consisted of patients who were prescribed duloxetine and (i) tested positive for duloxetine, (ii) tested negative for illicit substances and (iii) included creatinine, age and duloxetine dose administered. Of the 5,592 patient urines screened, 2,004 of the results fit into the inclusion criteria. Positive urine concentrations of duloxetine ranged from 50 to 2,722 ng/mL. Duloxetine urine concentrations were normalized to creatinine and dose further characterized by sex, age, body mass index (BMI) and dose in milligrams. Sample distribution included urines collected from 1,487 females and 517 males. The age range of the specimen donors was between 15 and 90 years old with an average age of 52. BMI levels ranged from 13.9 (underweight) to 88.1 (obese), with the average BMI being 33.5. The most common dose of duloxetine prescribed was a daily, oral dose of 60 mg. Analysis of the normalized, transformed creatinine concentrations showed that there was a significant statistical difference (P < 0.05) in the urinary duloxetine concentrations by sex and by dose (mg). Female patients further showed a statistical difference in urinary duloxetine concentration in age groups 18-64 and 64 and older. By characterizing urinary duloxetine concentrations in patients prescribed the medication, normalized distributions of data ranges have been established. These data ranges for urinary duloxetine concentrations can be used to determine patient compliance with duloxetine in routine, clinical samples.

Duloxetine overdose causes sympathomimetic and serotonin toxicity without major complications

OBJECTIVE

Duloxetine is a commonly used antidepressant that is a serotonin and norepinephrine reuptake inhibitor. We aimed to investigate the frequency and severity of clinical effects following duloxetine overdose.

METHODS

We undertook a retrospective review of duloxetine overdoses (>120 mg) admitted to two tertiary toxicology units between March 2007 and May 2021. Demographic information, details of ingestion (dose, co-ingestants), clinical effects, investigations (ECG parameters including QT interval), complications (coma [GCS < 9], serotonin toxicity, seizures and cardiovascular effects), length of stay [LOS] and intensive care unit [ICU] admission were extracted from a clinical database.

RESULTS

There were 241 duloxetine overdoses (>120 mg), median age 37 years (interquartile range [IQR]: 25-48 years) and there were 156 females (65%). The median dose was 735 mg (IQR: 405-1200 mg). In 177 patients, other medications were co-ingested, most commonly alcohol, paracetamol, quetiapine, diazepam, ibuprofen, pregabalin and oxycodone. These patients were more likely to be admitted to ICU (12 [7%] vs. none; p = 0.040), develop coma (16 [9%] vs. none; p = 0.008) and hypotension [systolic BP < 90 mmHg] (15 [8%] vs. one; p = 0.076). Sixty four patients ingested duloxetine alone with a median dose of 840 mg (180-4200 mg). The median LOS, in the duloxetine only group, was 13 h (IQR:8.3-18 h), which was significantly shorter than those taking coingestants, 19 h (IQR:12-31 h; p = 0.004). None of these patients were intubated. Six patients developed moderate serotonin toxicity, without complications and one had a single seizure. Tachycardia occurred in 31 patients (48%) and mild hypertension (systolic BP > 140 mmHg) in 29 (45%). One patient had persistent sympathomimetic toxicity, and one had hypotension after droperidol. Two patients of 63 with an ECG recorded had an abnormal QT: one QT 500 ms, HR 46 bpm, which resolved over 3.5 h and a second with tachycardia (QT 360 ms, HR 119 bpm). None of the 64 patients had an arrhythmia.

CONCLUSION

Duloxetine overdose most commonly caused sympathomimetic effects and serotonin toxicity, consistent with its pharmacology, and did not result in coma, arrhythmias or intensive care admission, when taken alone in overdose.

An overview of painful diabetic peripheral neuropathy: Diagnosis and treatment advancements

Diabetes mellitus remains a public health problem, affecting 422 million people worldwide. Currently, there is no consensus around treating painful diabetic peripheral neuropathy in a step-wise manner. Among the non-pharmacological interventions, neuromodulation has become a promising alternative. Over the past decade, significant clinical trials have paved the way for prompt inclusion of high-frequency spinal cord stimulation within the painful diabetic peripheral neuropathy treatment algorithm. This article aims to provide an updated evidence-based approach for the management of painful diabetic peripheral neuropathy.

A Look at Commonly Utilized Serotonin Noradrenaline Reuptake Inhibitors (SNRIs) in Chronic Pain

Purpose of Review

Chronic pain continues to be one of the leading healthcare cost burdens in the United States and is typically defined as ongoing pain, lasting longer than six months. Various treatment options exist for chronic pain, including physical therapy, medical management, pain psychology, and interventional therapies. Pain medications have been the mainstay of treatment for chronic pain conditions with an increasing use of membrane stabilizers and antidepressants to treat neuropathic pain conditions. Specifically, serotonin noradrenaline reuptake inhibitors (SNRIs) have been used to treat a range of pain conditions expanding from everyday use for depressive disorders.

Recent Findings

SNRIs, including duloxetine, venlafaxine, and milnacipran, have demonstrated efficacy in reducing pain in musculoskeletal pain (chronic low back pain and osteoarthritis), fibromyalgia, and neuropathic pain conditions (peripheral diabetic neuropathy).

Summary

The article describes the function, role, and use of SNRIs to treat chronic and neuropathic pain by altering the noradrenergic descending inhibitory pathways.

Inhibitory effects of fluoxetine and duloxetine on the pharmacokinetics of metoprolol in vivo and in vitro

Depression is common among people with cardiovascular diseases. Therefore, the combined use of antidepressants and cardiovascular drugs is very common, which increases the possibility of drug interaction. Simultaneously compare the effects of duloxetine and fluoxetine on metoprolol metabolism, and provide evidence-based guidance for medication safety. Sprague-Dawley rats were randomly divided into three groups: group A (10.3 mg/kg metoprolol alone), group B (10.3 mg/kg metoprolol + 6.2 mg/kg fluoxetine), and group C (10.3 mg/kg metoprolol + 6.2 mg/kg duloxetine). Tail vein blood was collected and subjected to the ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection. Moreover, in vitro inhibition of fluoxetine and duloxetine were assessed by incubating liver microsomes and CYP2D6.1 with metoprolol. In in vivo study, the administration of fluoxetine or duloxetine significantly increased the AUC_(0-𝑡) and AUC_(0-∞) of metoprolol (P < 0.05). Differences between fluoxetine and duloxetine in plasma concentration were also investigated, and their pharmacokinetic parameters such as AUC_(0-𝑡) and AUC_(0-∞) were significantly distinct (P < 0.05). In vitro, fluoxetine and duloxetine inhibited the metabolism of metoprolol via mixed competitive mechanism of cytochrome P450. IC₅₀ values of fluoxetine and duloxetine were 12.86 and 2.51 μM, respectively. Moreover, the metabolism rate of metoprolol was inhibited to 19.62% and 17.14% in recombinant human CYP2D6.1 by fluoxetine and duloxetine, respectively. Duloxetine showed a more significant inhibitory potential compared to fluoxetine in vitro, but the main pharmacokinetic parameters of fluoxetine and duloxetine revealed differences in inhibiting metoprolol metabolism in vivo.

Metabolism of a Selective Serotonin and Norepinephrine Reuptake Inhibitor Duloxetine in Liver Microsomes and Mice

Duloxetine (DLX) is a dual serotonin and norepinephrine reuptake inhibitor, widely used for the treatment of major depressive disorder. Although DLX has shown good efficacy and safety, serious adverse effects (e.g., liver injury) have been reported. The mechanisms associated with DLX-induced toxicity remain elusive. Drug metabolism plays critical roles in drug safety and efficacy. However, the metabolic profile of DLX in mice is not available, although mice serve as commonly used animal models for mechanistic studies of drug-induced adverse effects. Our study revealed 39 DLX metabolites in human/mouse liver microsomes and mice. Of note, 13 metabolites are novel, including five N-acetyl cysteine adducts and one reduced glutathione (GSH) adduct associated with DLX. Additionally, the species differences of certain metabolites were observed between human and mouse liver microsomes. CYP1A2 and CYP2D6 are primary enzymes responsible for the formation of DLX metabolites in liver microsomes, including DLX-GSH adducts. In summary, a total of 39 DLX metabolites were identified, and species differences were noticed in vitro. The roles of CYP450s in DLX metabolite formation were also verified using human recombinant cytochrome P450 (P450) enzymes and corresponding chemical inhibitors. Further studies are warranted to address the exact role of DLX metabolism in its adverse effects in vitro (e.g., human primary hepatocytes) and in vivo (e.g., Cyp1a2-null mice). SIGNIFICANCE STATEMENT: This current study systematically investigated Duloxetine (DLX) metabolism and bioactivation in liver microsomes and mice. This study provided a global view of DLX metabolism and bioactivation in liver microsomes and mice, which are very valuable to further elucidate the mechanistic study of DLX-related adverse effects and drug-drug interaction from metabolic aspects.

Kampo formulas alleviate aging-related emotional disturbances and neuroinflammation in male senescence-accelerated mouse prone 8 mice

Aging-induced neuroinflammation, also known as neuroinflammaging, plays a pivotal role in emotional disturbances, including depression and anxiety, in older individuals, thereby leading to cognitive dysfunction. Although numerous studies have focused on therapeutic strategies for cognitive impairment in older individuals, little research has been performed on treating its preceding emotional disturbances. Here, we examined whether Kampo formulas (kososan [KS], nobiletin-rich kososan [NKS], and hachimijiogan [HJG]) can ameliorate aging-induced emotional disturbances and neuroinflammation in mice. The depression-like behaviors observed in SAMP8 mice, relative to normally aging SAMR1 mice, were significantly prevented by treatment with Kampo formulas for 13 weeks. Western blot analysis revealed that hippocampal neuroinflammation was significantly abrogated by Kampo formulas. KS and NKS also significantly attenuated the hippocampal neuroinflammatory priming induced by lipopolysaccharide (LPS, 0.33 mg/kg, i.p.) challenge in SAMP8 mice. Hippocampal IL-1β, IL-6, and MCP-1 levels were significantly decreased in NKS-treated SAMP8 mice. KS and NKS showed significantly reduced tau accumulation in the brains of SAMP8 mice. RNA-sequencing revealed that each Kampo formula led to unique dynamics of hippocampal gene expression and appeared to abrogate hippocampal inflammatory responses. HJG significantly blocked the LPS-induced increase in serum IL-6 and MCP-1. These results suggest that Kampo formulas would be useful for treating aging-induced depression, in part by regulating neuroinflammatory pathways. This finding may pave the way for the development of therapeutic strategies for aging-related emotional disturbances, which may contribute to the prevention of cognitive dysfunction in older individuals.

Bioanalytical methods for the detection of duloxetine and thioctic acid in plasma using ultra performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS)

Duloxetine and thioctic acid (TA) are standard drugs for treating diabetic neuropathy, a primary complication associated with diabetes. In this study, ultra performance liquid chromatography coupled with tandem mass spectrometry methods was successfully developed and validated for quantifying duloxetine and TA in biological samples. The protein precipitation method was used to extract duloxetine, TA and their internal standards from beagle dog plasma. A Hypersil Gold C18 column (150 × 2.1 mm, 1.9 μm) was used for the experiment. Isocratic elution with 0.1% formic acid in acetonitrile (A) and 0.1% formic acid (B) was used for duloxetine, whereas a gradient elution with 0.03% acetic acid (A) and acetonitrile (B) was used for TA. The validated parameters included linearity, sensitivity, accuracy, precision, selectivity, matrix effect, stability, and recovery under different conditions. The linear ranges of the calibration curves for duloxetine and TA were 5–800 ng/mL and 5–1,000 ng/mL, respectively. An intra- and inter-run precision of ± 15% can be observed in all quality control samples. These methods were successfully used for pharmacokinetics (PKs) studies in beagle dogs to compare PK differences in a fixed-dose combination including duloxetine and TA and co-administration of the 2 drugs.

Design Strategies, Chemistry and Therapeutic Insights of Multi-target Directed Ligands as Antidepressant Agents

Depression is one of the major disorders of the central nervous system worldwide and causes disability and functional impairment. According to the World Health Organization, around 265 million people worldwide are affected by depression. Currently marketed antidepressant drugs take weeks or even months to show anticipated clinical efficacy but remain ineffective in treating suicidal thoughts and cognitive impairment. Due to the multifactorial complexity of the disease, single-target drugs do not always produce satisfactory results and lack the desired level of therapeutic efficacy. Recent literature reports have revealed improved therapeutic potential of multi-target directed ligands due to their synergistic potency and better safety. Medicinal chemists have gone to great extents to design multitarget ligands by generating structural hybrids of different key pharmacophores with improved binding affinities and potency towards different receptors or enzymes. This article has compiled the design strategies of recently published multi-target directed ligands as antidepressant agents. Their biological evaluation, structural-activity relationships, mechanistic and in silico studies have also been described. This article will prove to be highly useful for the researchers to design and develop multi-target ligands as antidepressants with high potency and therapeutic efficacy.

The Treatment of Painful Diabetic Neuropathy

Painful diabetic peripheral neuropathy (painful-DPN) is a highly prevalent and disabling condition, affecting up to one-third of patients with diabetes. This condition can have a profound impact resulting in a poor quality of life, disruption of employment, impaired sleep, and poor mental health with an excess of depression and anxiety. The management of painful-DPN poses a great challenge. Unfortunately, currently there are no Food and Drug Administration (USA) approved disease-modifying treatments for diabetic peripheral neuropathy (DPN) as trials of putative pathogenetic treatments have failed at phase 3 clinical trial stage. Therefore, the focus of managing painful- DPN other than improving glycaemic control and cardiovascular risk factor modification is treating symptoms. The recommended treatments based on expert international consensus for painful- DPN have remained essentially unchanged for the last decade. Both the serotonin re-uptake inhibitor (SNRI) duloxetine and α2δ ligand pregabalin have the most robust evidence for treating painful-DPN. The weak opioids (e.g. tapentadol and tramadol, both of which have an SNRI effect), tricyclic antidepressants such as amitriptyline and α2δ ligand gabapentin are also widely recommended and prescribed agents. Opioids (except tramadol and tapentadol), should be prescribed with caution in view of the lack of definitive data surrounding efficacy, concerns surrounding addiction and adverse events. Recently, emerging therapies have gained local licenses, including the α2δ ligand mirogabalin (Japan) and the high dose 8% capsaicin patch (FDA and Europe). The management of refractory painful-DPN is difficult; specialist pain services may offer off-label therapies (e.g. botulinum toxin, intravenous lidocaine and spinal cord stimulation), although there is limited clinical trial evidence supporting their use. Additionally, despite combination therapy being commonly used clinically, there is little evidence supporting this practise. There is a need for further clinical trials to assess novel therapeutic agents, optimal combination therapy and existing agents to determine which are the most effective for the treatment of painful-DPN. This article reviews the evidence for the treatment of painful-DPN, including emerging treatment strategies such as novel compounds and stratification of patients according to individual characteristics (e.g. pain phenotype, neuroimaging and genotype) to improve treatment responses.

Gene mining, codon optimization and analysis of binding mechanism of an aldo-keto reductase with high activity, better substrate specificity and excellent solvent tolerance

The biosynthesis of chiral alcohols has important value and high attention. Aldo–keto reductases (AKRs) mediated reduction of prochiral carbonyl compounds is an interesting way of synthesizing single enantiomers of chiral alcohols due to the high enantio-, chemo- and regioselectivity of the enzymes. However, relatively little research has been done on characterization and apply of AKRs to asymmetric synthesis of chiral alcohols. In this study, the AKR from Candida tropicalis MYA-3404 (C. tropicalis MYA-3404), was mined and characterized. The AKR shown wider optimum temperature and pH. The AKR exhibited varying degrees of catalytic activity for different substrates, suggesting that the AKR can catalyze a variety of substrates. It is worth mentioning that the AKR could catalytic reduction of keto compounds with benzene rings, such as cetophenone and phenoxyacetone. The AKR exhibited activity on N,N-dimethyl-3-keto-3-(2-thienyl)-1-propanamine (DKTP), a key intermediate for biosynthesis of the antidepressant drug duloxetine. Besides, the AKR still has high activity whether in a reaction system containing 10%-30% V/V organic solvent. What’s more, the AKR showed the strongest stability in six common organic solvents, DMSO, acetonitrile, ethyl acetate, isopropanol, ethanol, and methanol. And, it retains more that 70% enzyme activity after 6 hours, suggesting that the AKR has strong solvent tolerance. Furthermore, the protein sequences of the AKR and its homology were compared, and a 3D model of the AKR docking with coenzyme NADPH were constructed. And the important catalytic and binding sites were identified to explore the binding mechanism of the enzyme and its coenzyme. These properties, predominant organic solvents resistance and extensive substrate spectrum, of the AKR making it has potential applications in the pharmaceutical field.

Tools for optimising pharmacotherapy in psychiatry (therapeutic drug monitoring, molecular brain imaging and pharmacogenetic tests): focus on antidepressants

Objectives: More than 40 drugs are available to treat affective disorders. Individual selection of the optimal drug and dose is required to attain the highest possible efficacy and acceptable tolerability for every patient.Methods: This review, which includes more than 500 articles selected by 30 experts, combines relevant knowledge on studies investigating the pharmacokinetics, pharmacodynamics and pharmacogenetics of 33 antidepressant drugs and of 4 drugs approved for augmentation in cases of insufficient response to antidepressant monotherapy. Such studies typically measure drug concentrations in blood (i.e. therapeutic drug monitoring) and genotype relevant genetic polymorphisms of enzymes, transporters or receptors involved in drug metabolism or mechanism of action. Imaging studies, primarily positron emission tomography that relates drug concentrations in blood and radioligand binding, are considered to quantify target structure occupancy by the antidepressant drugs in vivo. Results: Evidence is given that in vivo imaging, therapeutic drug monitoring and genotyping and/or phenotyping of drug metabolising enzymes should be an integral part in the development of any new antidepressant drug.Conclusions: To guide antidepressant drug therapy in everyday practice, there are multiple indications such as uncertain adherence, polypharmacy, nonresponse and/or adverse reactions under therapeutically recommended doses, where therapeutic drug monitoring and cytochrome P450 genotyping and/or phenotyping should be applied as valid tools of precision medicine.

Two facile approaches based on association complex with erythrosine-B for nano-level analysis of duloxetine: application to content uniformity

Duloxetine is an antidepressant that exhibits its action by preventing the reuptake of serotonin and norepinephrine by neurons. In this analytical study, we developed two facile, sensitive methods for duloxetine analysis. Both methods rely on the formation of binary association complex between erythrosine-B and duloxetine in an acidic medium using spectrofluorimetric and resonance Rayleigh scattering (RRS) techniques. Spectrofluorimetric method simply uses the quenching property of the formed complex on the native fluorescence of erythrosine-B at an emission wavelength of 557.2 nm (λ ex = 528.6), while RRS is based on detecting the enhancement in the RRS signal at 357.2 nm. The proposed methods have been validated according to the International Conference on Harmonization guidelines. The approaches provide linear assay of duloxetine hydrochloride over 0.1-2.4 µg ml-1 and 0.2-2.0 µg ml-1 for spectrofluorimetric and RRS methods, respectively. Variables affecting methods and complex formation were studied and optimized. The limit of detection values were 0.03 and 0.056 µg ml-1 for spectrofluorimetric and RRS methods, respectively. Both approaches were applied with acceptable results for formulation analysis and evaluation of cymbatex capsule content uniformity.

Precision Medicine into Clinical Practice: A Web-Based Tool Enables Real-Time Pharmacogenetic Assessment of Tailored Treatments in Psychiatric Disorders

The management of neuropsychiatric disorders involves different pharmacological treatments. In order to perform efficacious drug treatments, the metabolism of CYP genes can help to foresee potential drug–drug interactions. The NeuroPGx software is an open-source web-based tool for genotype/diplotype/phenotype interpretation for neuropharmacogenomic purposes. The software provides information about: (i) the genotypes of evaluated SNPs (single nucleotide polymorphisms); (ii) the main diplotypes in CYP genes and corresponding metabolization phenotypes; (iii) the list of neuropsychiatric drugs with recommended dosage adjustment (according to CPIC and DPWG guidelines); (iv) the list of possible (rare) diplotypes and corresponding metabolization phenotypes. The combined application of NeuroPGx software to the OpenArray technology results in an easy, quick, and highly automated device ready to be used in routine clinical practice.

Suppression of cigarette smoke induced MMP1 expression by selective serotonin re-uptake inhibitors

Globally, COPD remains a major cause of disability and death. In the United States alone, it is estimated that approximately 14 million people suffer from the disease. Given the high disease burden and requirement for chronic, long‐term medical care associated with COPD, it is essential that new disease modifying agents are developed to complement the symptomatic therapeutics currently available. In the present report, we have identified a potentially novel therapeutic agent through the use of a high throughput screen based on the knowledge that cigarette smoke induces the proteolytic enzyme MMP1 leading to destruction of the lung in COPD. A construct utilizing the cigarette responsive promoter element of MMP‐1 was conjugated to a luciferase reporter and utilized in an in vitro assay to screen the NIH Molecular Libraries Small Molecule Repository to identify putative targets that suppressed luciferase expression in response to cigarette smoke extract (CSE). Selective serotonin reuptake inhibitors potently inhibited luciferase expression and were further validated. SSRI treatment suppressed MMP‐1 production in small airway epithelial cells exposed to (CSE) in vitro as well as in smoke exposed rabbits. In addition, SSRI treatment inhibited inflammatory cytokine production while rescuing cigarette smoke induced downregulation in vivo of the anti‐inflammatory lipid transporter ABCA1, previously shown by our laboratory to be lung protective. Importantly, SSRI treatment prevented lung destruction in smoke exposed rabbits as measured by morphometry. These studies support further investigation into SSRIs as a novel therapeutic for COPD may be warranted.

Duloxetine reduces pain after Total hip arthroplasty: a prospective, randomized controlled study

BACKGROUND

Previous studies have demonstrated the efficacy of duloxetine in reducing postoperative pain and opioid consumption. However, the effect of duloxetine on total hip arthroplasty (THA) remains unclear. The objective of this study was to assess the efficacy of oral duloxetine in THA.

METHODS

We enrolled 96 patients in this randomized controlled trial. These patients were randomized (1,1) to either the duloxetine group or the placebo group and received daily doses of 60 mg duloxetine or placebo, respectively, from 2 d pre-operation to 14 d after surgery. The primary outcome was pain severity upon movement measured by a visual analogue scale (VAS). The secondary outcomes included VAS scores for resting pain, morphine consumption, Harris Hip Score, patient satisfaction at discharge, length of postoperative hospital stay, and adverse events.

RESULTS

Patients in the duloxetine group had significantly lower pain severity scores upon movement within 3 postoperative weeks (p < 0.05) while none of the differences met the minimum clinically important difference (MCID). Moreover, patients in the duloxetine group performed better in terms of resting pain (in 3 weeks after surgery), morphine requirements, and satisfaction level at discharge (all p < 0.05). There was no difference between groups in the prevalence of adverse events.

CONCLUSIONS

Although it did not result in a clinically meaning reduction in pain after total hip arthroplasty, perioperative administration of 60 mg of duloxetine daily significantly alleviated pain in the postoperative 3 weeks and morphine requirements during the postoperative 48 h. Therefore, duloxetine still shows promise in optimizing the multimodal pain-management protocols in total hip arthroplasty.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2000033606 , 06/06/2020.

Evaluation of Switch-to-Brand Rates as a Potential Signal for Therapeutic Equivalency of Generic Antidepressants: A Real-World Retrospective Cohort Study

Negative clinical outcomes after switching from brand to generic antidepressants have raised concerns regarding therapeutic equivalency. This research aims to estimate the prevalence of switching and to identify predictors for generic to brand switching for various antidepressants. This retrospective cohort study utilized data from a 10% random sample of enrollees in the IQVIA PharMetrics Plus claims database from 2007-2015. The base cohort consisted of commercially insured patients who were prescribed escitalopram, duloxetine, or venlafaxine extended release (ER) anytime from the year prior to the generic launch through December 2014. The primary outcome was defined as a switch from generic to a brand within 14 days of sustained generic use in a 1-year follow-up period. Adjusted logistic regression and generalized estimating equations for repeated measures estimated the drug specific and overall odds of switch-to-brand among brand initiators relative to generic initiators, respectively. A total of 102,831 unique patients across 3 drug products contributed to the final analytic sample. The overall prevalence of switch from generic to brand was 0.74%. Across all three antidepressants, brands initiators were more likely to experience a switch-to-brand: escitalopram (odds ratio (OR): 14.41, 95% confidence interval (CI): 11.14-18.64), duloxetine (OR: 8.08, 95% CI: 4.85-13.41) and venlafaxine ER (OR: 16.46, 95% CI: 11.56-23.46). The pooled odds of a switch-to-brand in brand vs. generic initiators was 13.77 (95% CI: 11.35-16.71). This study suggests a low overall switch-to-brand prevalence and may support therapeutic equivalence between brand and generic antidepressants. Initiating with a brand product was the strongest predictor for switching back to brand and suggests that patient experience may play a role in drug utilization.

Antidepressant Screening Demonstrated Non-Monotonic Responses to Amitriptyline, Amoxapine and Sertraline in Locomotor Activity Assay in Larval Zebrafish

Antidepressants are well-known drugs to treat depression and major depressive disorder for humans. However, the misuse and abuse of antidepressants keep increasing with several side effects reported. The aim of this study was to assess the potential adverse effects of 18 antidepressants by monitoring zebrafish larval locomotor activity performance based on the total distance traveled, burst movement count, and total rotation count at four dark-light intercalated phases. In general, zebrafish larvae displayed sedative effects after antidepressant exposure by showing a significant reduction in all of the locomotor activity-related endpoints. However, three antidepressants i.e., amitriptyline, amoxapine, and sertraline were able to trigger a significantly high locomotor activity in zebrafish larvae during the light cycle. These differences might be due to the pharmacologic differences among the antidepressants. In addition, since each antidepressant possesses a different dosage range from the other, overdoses of these antidepressants might also be the causes of these differences. Furthermore, based on these results, a further study was conducted to observe the effect of these three antidepressants in lower concentrations. From the results, biphasic effects in terms of zebrafish larval locomotor activity were demonstrated by these drugs. Even though further studies are still required to validate the mechanism, these findings indicate that these antidepressants might share a common mechanism responsible for their effects on zebrafish larval locomotor activity although there were some differences in potency of these effects.

Expert consensus on the diagnosis and treatment of myofascial pain syndrome

Myofascial pain syndrome (MPS) is characterized by myofascial trigger points and fascial constrictions. At present, domestic and foreign scholars have not reached a consensus on the etiology and pathogenesis of MPS. Due to the lack of specific laboratory indicators and imaging evidence, there is no unified diagnostic criteria for MPS, making it easy to confuse with other diseases. The Chinese Association for the Study of Pain organized domestic experts to formulate this Chinese Pain Specialist Consensus on the diagnosis and treatment of MPS. This article reviews relevant domestic and foreign literature on the definition, epidemiology, pathogenesis, clinical manifestation, diagnostic criteria and treatments of MPS. The consensus is intended to normalize the diagnosis and treatment of MPS and be used by first-line doctors, including pain physicians to manage patients with MPS.