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Korean Journal of Anesthesiology Aug 2019Dexmedetomidine is a potent, highly selective α-2 adrenoceptor agonist, with sedative, analgesic, anxiolytic, sympatholytic, and opioid-sparing properties.... (Review)
Review
Dexmedetomidine is a potent, highly selective α-2 adrenoceptor agonist, with sedative, analgesic, anxiolytic, sympatholytic, and opioid-sparing properties. Dexmedetomidine induces a unique sedative response, which shows an easy transition from sleep to wakefulness, thus allowing a patient to be cooperative and communicative when stimulated. Dexmedetomidine may produce less delirium than other sedatives or even prevent delirium. The analgesic effect of dexmedetomidine is not strong; however, it can be administered as a useful analgesic adjuvant. As an anesthetic adjuvant, dexmedetomidine decreases the need for opioids, inhalational anesthetics, and intravenous anesthetics. The sympatholytic effect of dexmedetomidine may provide stable hemodynamics during the perioperative period. Dexmedetomidine-induced cooperative sedation with minimal respiratory depression provides safe and acceptable conditions during neurosurgical procedures in awake patients and awake fiberoptic intubation. Despite the lack of pediatric labelling, dexmedetomidine has been widely studied for pediatric use in various applications. Most adverse events associated with dexmedetomidine occur during or shortly after a loading infusion. There are some case reports of dexmedetomidine-related cardiac arrest following severe bradycardia. Some extended applications of dexmedetomidine discussed in this review are promising, but still limited, and further research is required. The pharmacological properties and possible adverse effects of dexmedetomidine should be well understood by the anesthesiologist prior to use. Moreover, it is necessary to select patients carefully and to determine the appropriate dosage of dexmedetomidine to ensure patient safety.
Topics: Adrenergic alpha-2 Receptor Agonists; Delirium; Dexmedetomidine; Dose-Response Relationship, Drug; Humans; Hypnotics and Sedatives; Patient Selection
PubMed: 31220910
DOI: 10.4097/kja.19259 -
Drugs Aug 2021Budesonide/glycopyrronium/formoterol (BREZTRI AEROSPHERE™; TRIXEO AEROSPHERE™) is an inhaled fixed-dose combination of the inhaled corticosteroid (ICS) budesonide,... (Review)
Review
Budesonide/glycopyrronium/formoterol (BREZTRI AEROSPHERE™; TRIXEO AEROSPHERE™) is an inhaled fixed-dose combination of the inhaled corticosteroid (ICS) budesonide, the long-acting muscarinic antagonist (LAMA) glycopyrronium bromide and the long-acting β-agonist (LABA) formoterol fumarate approved for the maintenance treatment of chronic obstructive pulmonary disease (COPD). It is delivered via a pressurized metered-dose Aerosphere inhaler and is formulated using co-suspension delivery technology. In two pivotal phase III trials of 24-52 weeks' duration, budesonide/glycopyrronium/formoterol reduced the rates of moderate/severe COPD exacerbations and improved lung function to a greater extent than budesonide/formoterol and/or glycopyrronium/formoterol. Budesonide/glycopyrronium/formoterol also demonstrated beneficial effects on dyspnoea, rescue medication requirements and health-related quality of life (HR-QOL), and reduced the risk of all-cause mortality. Budesonide/glycopyrronium/formoterol was generally well tolerated, with the tolerability profile being generally similar to that of the individual components. Budesonide/glycopyrronium/formoterol provides a useful and convenient option for the maintenance treatment of COPD, including for patients whose disease is inadequately controlled with dual ICS/LABA or LAMA/LABA therapy.
Topics: Administration, Inhalation; Adrenergic beta-2 Receptor Agonists; Bronchodilator Agents; Budesonide; Drug Combinations; Formoterol Fumarate; Glucocorticoids; Glycopyrrolate; Humans; Metered Dose Inhalers; Muscarinic Antagonists; Pulmonary Disease, Chronic Obstructive
PubMed: 34342835
DOI: 10.1007/s40265-021-01562-6 -
Drug Design, Development and Therapy 2023Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical... (Review)
Review
Peripheral nerve block technology is important to balanced anesthesia technology. It can effectively reduce opioid usage. It is the key to enhance clinical rehabilitation as an important part of the multimodal analgesia scheme. The emergence of ultrasound technology has accelerated peripheral nerve block technology development. It can directly observe the nerve shape, surrounding tissue, and diffusion path of drugs. It can also reduce the dosage of local anesthetics by improving positioning accuracy while enhancing the block's efficacy. Dexmedetomidine is a highly selective drug α-adrenergic receptor agonist. Dexmedetomidine has the characteristics of sedation, analgesia, anti-anxiety, inhibition of sympathetic activity, mild respiratory inhibition, and stable hemodynamics. Numerous studies have revealed that dexmedetomidine in peripheral nerve blocks can shorten the onset time of anesthesia and prolong the time of sensory and motor nerve blocks. Although dexmedetomidine was approved by the European Drug Administration for sedation and analgesia in 2017, it has not yet been approved by the US Food and Drug Administration (FDA). It is used as a non-label drug as an adjuvant. Therefore, the risk-benefit ratio must be evaluated when using these drugs as adjuvants. This review explains the pharmacology and mechanism of dexmedetomidine, the effect of dexmedetomidine on various peripheral nerve block as an adjuvant, and compare it with other types of adjuvants. We summarized and reviewed the application progress of dexmedetomidine as an adjuvant in nerve block and look forward to its future research direction.
Topics: United States; Dexmedetomidine; Adjuvants, Immunologic; Anesthetics, Local; Nerve Block; Adrenergic alpha-2 Receptor Agonists; Peripheral Nerves
PubMed: 37220544
DOI: 10.2147/DDDT.S405294 -
JAMA Feb 2022Acute agitation is common in patients with bipolar disorder and requires urgent management to relieve distress and to prevent escalation to aggressive behavior. (Comparative Study)
Comparative Study Randomized Controlled Trial
IMPORTANCE
Acute agitation is common in patients with bipolar disorder and requires urgent management to relieve distress and to prevent escalation to aggressive behavior.
OBJECTIVE
To evaluate the effect of orally absorbed, sublingual dexmedetomidine, a selective α2A-adrenergic receptor agonist on symptoms of acute agitation in patients with bipolar disorder.
DESIGN, SETTING, AND PARTICIPANTS
Phase 3, randomized, double-blind, placebo-controlled trial conducted in 15 sites in the US with enrollment between February 24, 2020, and April 27, 2020, and final follow-up on May 21, 2020. A total of 380 adults with bipolar I or II disorder were randomized and 362 completed the study.
INTERVENTIONS
Participants were randomized to 3 groups: sublingual dexmedetomidine 180 μg (n = 127), sublingual dexmedetomidine 120 μg (n = 127), or placebo (n = 126).
MAIN OUTCOMES AND MEASURES
The primary efficacy end point was the mean change from baseline at 2 hours for the Positive and Negative Syndrome Scale-Excited Component (PEC) total score. The range of possible total scores is 5 (absence of agitation) to 35 (extremely severe). The secondary end point was the earliest time of a statistically significant change in PEC total score from baseline for the drug vs placebo. On the primary efficacy end point, to account for multiplicity associated with comparing 2 sublingual dexmedetomidine doses with placebo, the 2-sided significance level for each dose vs placebo was set at .025.
RESULTS
Of 380 patients randomized (mean age, 45.6 years; 54.8% women; and 56.1% Black individuals), 378 (99.5%) self-administered the study medication and completed the study. Baseline agitation was mild to moderate, with an overall mean PEC total score of 18.0. Two hours after taking the medication, the mean changes from baseline in PEC total score were -10.4 for sublingual dexmedetomidine 180 μg, -9.0 for sublingual dexmedetomidine 120 μg, and -4.9 for placebo. Least-square mean differences from placebo in the sublingual dexmedetomidine groups at 2 hours were -5.4 (97.5% CI, -6.6 to -4.2) for 180 μg and -4.1 (97.5% CI, -5.3 to -2.9) for 120 μg (both doses P < .001 vs placebo). Treatment effects began 20 minutes after taking the medication among patients in the sublingual dexmedetomidine groups (least-square mean difference for 180 μg, -1.1 [97.5% CI, -2.0 to -0.2]; P = .007; for 120 μg, -1.0 [97.5% CI, -1.9 to -0.1]; P = .009). Adverse events occurred in 35.7% of patients taking 180 μg of dexmedetomidine, 34.9% taking 120 μg, and 17.5% taking placebo. The most common adverse events (≥5%) in the respective 180 μg, 120 μg, and placebo groups were somnolence (21.4% and 20.6% vs 4.8%); dry mouth (4.8% and 7.1% vs 0.8%); hypotension (6.3% and 4.8% vs 0%); and dizziness (5.6% and 5.6% vs 0.8%).
CONCLUSIONS AND RELEVANCE
Among patients with mild to moderate agitation associated with bipolar disorder, treatment with a sublingual film formulation of dexmedetomidine 120 μg or 180 μg, compared with placebo, resulted in significantly greater reduction in the agitation score at 2 hours. Further research is needed to understand the spectrum of patients for whom this treatment would be effective and feasible and to better understand the clinical importance of the observed effect size.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT04276883.
Topics: Administration, Sublingual; Adolescent; Adrenergic alpha-2 Receptor Agonists; Adult; Aged; Bipolar Disorder; Dexmedetomidine; Double-Blind Method; Female; Humans; Hypnotics and Sedatives; Male; Middle Aged; Psychomotor Agitation
PubMed: 35191924
DOI: 10.1001/jama.2022.0799 -
Science (New York, N.Y.) Dec 2023Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) bind to extracellular ligands and drugs and modulate intracellular responses...
Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs) bind to extracellular ligands and drugs and modulate intracellular responses through conformational changes. Despite their importance as drug targets, the molecular origins of pharmacological properties such as efficacy (maximum signaling response) and potency (the ligand concentration at half-maximal response) remain poorly understood for any ligand-receptor-signaling system. We used the prototypical adrenaline-β2 adrenergic receptor-G protein system to reveal how specific receptor residues decode and translate the information encoded in a ligand to mediate a signaling response. We present a data science framework to integrate pharmacological and structural data to uncover structural changes and allosteric networks relevant for ligand pharmacology. These methods can be tailored to study any ligand-receptor-signaling system, and the principles open possibilities for designing orthosteric and allosteric compounds with defined signaling properties.
Topics: Humans; Adrenergic beta-2 Receptor Agonists; Allosteric Regulation; Biosensing Techniques; Ligands; Protein Conformation; Receptors, Adrenergic, beta-2; Signal Transduction; Bioluminescence Resonance Energy Transfer Techniques
PubMed: 38127743
DOI: 10.1126/science.adh1859 -
Neurobiology of Learning and Memory Dec 2020The selective norepinephrine (NE) α2A-adrenoceptor (α2A-AR) agonist, guanfacine (Intuniv™), is FDA-approved for treating Attention Deficit Hyperactivity Disorder... (Review)
Review
The selective norepinephrine (NE) α2A-adrenoceptor (α2A-AR) agonist, guanfacine (Intuniv™), is FDA-approved for treating Attention Deficit Hyperactivity Disorder (ADHD) based on research in animals, a translational success story. Guanfacine is also widely used off-label in additional mental disorders that involve impaired functioning of the prefrontal cortex (PFC), including stress-related disorders such as substance abuse, schizotypic cognitive deficits, and traumatic brain injury. The PFC subserves high order cognitive and executive functions including working memory, abstract reasoning, insight and judgment, and top-down control of attention, action and emotion. These abilities arise from PFC microcircuits with extensive recurrent excitation through NMDAR synapses. There is powerful modulation of these synapses, where cAMP-PKA opening of nearby potassium (K) channels can rapidly and dynamically alter synaptic strength to coordinate arousal state with cognitive state, e.g. to take PFC "offline" during uncontrollable stress. A variety of evidence shows that guanfacine acts within the PFC via post-synaptic α2A-AR on dendritic spines to inhibit cAMP-PKA-K channel signaling, thus strengthening network connectivity, enhancing PFC neuronal firing, and improving PFC cognitive functions. Although guanfacine's beneficial effects are present in rodent, they are especially evident in primates, where the PFC greatly expands and differentiates. In addition to therapeutic actions in PFC, stress-related disorders may also benefit from additional α2-AR actions, such as weakening plasticity in the amygdala, reducing NE release, and anti-inflammatory actions by deactivating microglia. Altogether, these NE α2-AR actions optimize top-down control by PFC networks, which may explain guanfacine's benefits in a variety of mental disorders.
Topics: Adrenergic alpha-2 Receptor Agonists; Animals; Attention Deficit Disorder with Hyperactivity; Cognition; Cognition Disorders; Guanfacine; Humans; Macaca mulatta; Memory, Short-Term; Mice; Nerve Net; Neurons; Prefrontal Cortex; Rats; Synapses
PubMed: 33075480
DOI: 10.1016/j.nlm.2020.107327 -
Molecular Medicine Reports Jul 2020Cardiac dysfunction resulting from sepsis may cause significant morbidity and mortality, and ferroptosis plays a role in this pathology. Dexmedetomidine (Dex), a...
Cardiac dysfunction resulting from sepsis may cause significant morbidity and mortality, and ferroptosis plays a role in this pathology. Dexmedetomidine (Dex), a α2‑adrenergic receptor (α2‑AR) agonist exerts cardioprotective effects against septic heart dysfunction, but the exact mechanism is unknown. In the present study, sepsis was induced by cecal ligation and puncture (CLP) in male C57BL/6 mice. Dex and yohimbine hydrochloride (YOH), an α2‑AR inhibitor, were administered before inducing CLP. Then, 24 h after CLP, serum and heart tissue were collected to detect changes of troponin‑I (TN‑I), interleukin 6 (IL‑6), superoxide dismutase (SOD), malonaldehyde (MDA) and glutathione (GSH) levels, and iron release. Ferroptosis‑targeting proteins, apoptosis and inflammatory factors were assessed by western blotting or ELISA. It was found that, 24 h after CLP, TN‑I, a biomarker of myocardial injury, was significantly increased compared with the control group. Furthermore, the levels of MDA, 8‑hydroxy‑2'‑deoxyguanosine and the inflammatory factors IL‑6 and monocyte chemoattractant protein‑1 were also significantly increased. It was demonstrated that treatment with Dex reverted or attenuated these changes (CLP + Dex vs. CLP; P<0.05), but these protective effects of Dex were reversed by YOH. Moreover, CLP significantly decreased the protein expression levels of glutathione peroxidase 4 (GPX4), SOD and GSH. However, CLP increased expression levels of heme oxygenase‑1 (HO‑1), transferrin receptor, cleaved caspase 3, inducible nitric oxide synthase and gasdermin D, and iron concentrations. It was found that Dex reversed these changes, but YOH abrogated the protective effects of Dex (CLP + Dex + YOH vs. CLP + Dex; P<0.05). Therefore, the present results suggested that the attenuation of sepsis‑induced HO‑1 overexpression and iron concentration, and the reduction of ferroptosis via enhancing GPX4, may be the major mechanisms via which Dex alleviates sepsis‑induced myocardial cellular injury.
Topics: Adrenergic alpha-2 Receptor Agonists; Animals; Dexmedetomidine; Ferroptosis; Heart; Heart Injuries; Male; Mice, Inbred C57BL; Myocardium; Sepsis
PubMed: 32377745
DOI: 10.3892/mmr.2020.11114 -
Science (New York, N.Y.) Sep 2022Because nonopioid analgesics are much sought after, we computationally docked more than 301 million virtual molecules against a validated pain target, the α-adrenergic...
Because nonopioid analgesics are much sought after, we computationally docked more than 301 million virtual molecules against a validated pain target, the α-adrenergic receptor (αAR), seeking new αAR agonists chemotypes that lack the sedation conferred by known αAR drugs, such as dexmedetomidine. We identified 17 ligands with potencies as low as 12 nanomolar, many with partial agonism and preferential G and G signaling. Experimental structures of αAR complexed with two of these agonists confirmed the docking predictions and templated further optimization. Several compounds, including the initial docking hit '9087 [mean effective concentration (EC) of 52 nanomolar] and two analogs, '7075 and PS75 (EC 4.1 and 4.8 nanomolar), exerted on-target analgesic activity in multiple in vivo pain models without sedation. These newly discovered agonists are interesting as therapeutic leads that lack the liabilities of opioids and the sedation of dexmedetomidine.
Topics: Adrenergic alpha-2 Receptor Agonists; Analgesics, Non-Narcotic; Animals; Dexmedetomidine; Drug Design; Drug Discovery; Humans; Ligands; Mice; Molecular Docking Simulation; Pain; Pain Management; Structure-Activity Relationship
PubMed: 36173843
DOI: 10.1126/science.abn7065 -
The Journal of Clinical Psychiatry Oct 2022Determine if sublingual dexmedetomidine, a selective α adrenergic receptor agonist, reduces symptoms of acute agitation associated with schizophrenia or... (Randomized Controlled Trial)
Randomized Controlled Trial
Determine if sublingual dexmedetomidine, a selective α adrenergic receptor agonist, reduces symptoms of acute agitation associated with schizophrenia or schizoaffective disorder. This phase 3, randomized, double-blind, placebo-controlled study was conducted in adults diagnosed with schizophrenia or schizoaffective disorder per the , Fifth Edition () criteria. The study was conducted at 15 US sites between January 23, 2020, and May 8, 2020. Participants were randomized to sublingual dexmedetomidine 180 μg, 120 μg, or matching placebo. The primary efficacy endpoint was mean change from baseline in the Positive and Negative Syndrome Scale-Excited Component (PEC) total score at 2 hours postdose. Altogether, 380 participants (mean age 45.6 years, 63.4% identifying as male, 77.9% identifying as Black or African American) were randomized; 380 (100%) self-administered study medication, and 372 (97.9%) completed the study. The mean PEC total score at baseline (17.6) indicated mild to moderate agitation. At 2 hours postdose, the least squares mean changes (SE) from baseline were -10.3 (0.4) for sublingual dexmedetomidine 180 μg, -8.5 (0.4) for 120 μg, and -4.8 (0.4) for placebo. Least squares mean differences (97.5% confidence intervals) in the sublingual dexmedetomidine groups were -5.5 (-6.7 to -4.3) for 180 μg and -3.7 (-4.9 to -2.5) for 120 μg (both < .001 vs placebo). The most commonly encountered adverse events with dexmedetomidine (incidence ≥ 5% and ≥ 2× rate observed with placebo) were somnolence, dry mouth, and hypotension for the 120 μg dose, and somnolence, dizziness, orthostatic hypotension, and oral hypoesthesia for the 180 μg dose. Treatment with sublingual dexmedetomidine 180 μg or 120 μg was more efficacious than placebo in reducing acute agitation associated with schizophrenia as measured by PEC scores at 2 hours postdose. ClinicalTrials.gov identifier: NCT04268303.
Topics: Adrenergic alpha-2 Receptor Agonists; Adult; Antipsychotic Agents; Dexmedetomidine; Double-Blind Method; Humans; Male; Middle Aged; Psychotic Disorders; Schizophrenia; Sleepiness; Treatment Outcome
PubMed: 36198061
DOI: 10.4088/JCP.22m14447 -
Advances in Therapy Nov 2021In the absence of head-to-head trials, we performed an indirect treatment comparison of the β-adrenergic agonists vibegron and mirabegron in the treatment of overactive...
BACKGROUND
In the absence of head-to-head trials, we performed an indirect treatment comparison of the β-adrenergic agonists vibegron and mirabegron in the treatment of overactive bladder (OAB).
METHODS
PubMed, Embase, and Cochrane Library were searched for articles related to phase 3, double-blind, controlled trials of vibegron 75 mg and mirabegron 25/50 mg in patients with OAB. Efficacy outcomes included change from baseline at weeks 4, 12, and 52 in mean daily number of total urinary incontinence episodes and micturitions and mean volume voided/micturition. Effect size was computed as placebo-subtracted change from baseline (weeks 4, 12) or active control (tolterodine)-subtracted change from baseline (week 52) for each treatment group. Adverse events (AEs) are presented descriptively.
RESULTS
After removal of duplicates, 49 records were identified, and after screening 9 met inclusion criteria for analysis. Vibegron showed significantly greater reduction in mean daily number of total incontinence episodes than mirabegron 25 mg at week 4, mirabegron 50 mg (weeks 4, 52), and tolterodine (weeks 4, 12) (P < 0.05, each) and significantly greater improvement in volume voided versus mirabegron 25 mg (week 12), mirabegron 50 mg (weeks 12, 52), and tolterodine (week 4) (P < 0.05, each). Confidence intervals of point estimates overlapped zero for all other comparisons of vibegron and mirabegron (25 or 50 mg) or tolterodine, indicating no significant differences between treatments for these time/endpoints. Urinary tract infection, hypertension, and dry mouth were the most commonly occurring AEs for vibegron, mirabegron, and tolterodine, respectively, in the short-term trials; hypertension was the most commonly occurring AE with all three treatments in the long-term trials.
CONCLUSIONS
Vibegron was associated with significant improvement in total incontinence episodes versus mirabegron at 4 and 52 weeks and volume voided at 12 and 52 weeks. Improvement in micturitions was similar between vibegron and mirabegron or tolterodine. Incidence of AEs was generally comparable between vibegron and mirabegron.
Topics: Acetanilides; Adrenergic beta-3 Receptor Agonists; Clinical Trials, Phase III as Topic; Double-Blind Method; Humans; Muscarinic Antagonists; Pyrimidinones; Pyrrolidines; Randomized Controlled Trials as Topic; Thiazoles; Treatment Outcome; Urinary Bladder, Overactive
PubMed: 34537953
DOI: 10.1007/s12325-021-01902-8