Oral docetaxel plus encequidar - A pharmacokinetic model and evaluation against IV docetaxel.

The development of optimized dosing regimens plays a crucial role in oncology drug development. This study focused on the population pharmacokinetic modelling and simulation of docetaxel, comparing the pharmacokinetic exposure of oral docetaxel plus encequidar (oDox + E) with the standard of care intravenous (IV) docetaxel regimen. The aim was to evaluate the feasibility of oDox + E as a potential alternative to IV docetaxel. The article demonstrates an approach which aligns with the FDA's Project Optimus which aims to improve oncology drug development through model informed drug development (MIDD). The key question answered by this study was whether a feasible regimen of oDox + E existed. The purpose of this question was to provide an early GO / NO-GO decision point to guide drug development and improve development efficiency. METHODS:  A stepwise approach was employed to develop a population pharmacokinetic model for total and unbound docetaxel plasma concentrations after IV docetaxel and oDox + E administration. Simulations were performed from the final model to assess the probability of target attainment (PTA) for different oDox + E dose regimens (including multiple dose regimens) in relation to IV docetaxel using AUC over effective concentration (AUCOEC) metric across a range of effective concentrations (EC). A Go / No-Go framework was defined-the first part of the framework assessed whether a feasible oDox + E regimen existed (i.e., a PTA ≥ 80%), and the second part defined the conditions to proceed with a Go decision. RESULTS:  The overall population pharmacokinetic model consisted of a 3-compartment model with linear elimination, constant bioavailability, constant binding mechanics, and a combined error model. Simulations revealed that single dose oDox + E regimens did not achieve a PTA greater than 80%. However, two- and three-dose regimens at 600 mg achieved PTAs exceeding 80% for certain EC levels. CONCLUSION:  The study demonstrates the benefits of MIDD using oDox + E as a motivating example. A population pharmacokinetic model was developed for the total and unbound concentration in plasma of docetaxel after administration of IV docetaxel and oDox + E. The model was used to simulate oDox + E dose regimens which were compared to the current standard of care IV docetaxel regimen. A GO / NO-GO framework was applied to determine whether oDox + E should progress to the next phase of drug development and whether any conditions should apply. A two or three-dose regimen of oDox + E at 600 mg was able to achieve non-inferior pharmacokinetic exposure to current standard of care IV docetaxel in simulations. A Conditional GO decision was made based on this result and further quantification of the "effective concentration" would improve the ability to optimise the dose regimen.

Pharmacokinetics in Penguins Compared to Other Avian Species: A Review of Enrofloxacin and Voriconazole.

Australasia is home to unique and endangered avian species. Drug administration to this group of animal patients for prophylaxis and treatment is challenging from a number of different perspectives. A key limitation for optimal drug dosing in birds is the lack of published pharmacokinetic studies to guide dose requirements. The aim of this review was to systematically investigate published literature on pharmacokinetics in penguin species and compare that with the pharmacokinetics of other avian species with a focus on two drugs: enrofloxacin and voriconazole. The review was conducted following PRISMA guidelines. A systematic literature search was performed in Pubmed, Embase, Scopus, and Web of Science databases. A key finding is that penguin pharmacokinetics differs from other avian species, with weight-adjusted AUC and Cmax values higher than most other avian species (e.g., for enrofloxacin, the AUC in the African penguin is 85.7 µg h/mL, which is more than double the other bird species). Doses for some avian species may be successfully extrapolated from other avian species; however, it appears important to consider factors other than just body weight (e.g., clearance mechanism and drug physicochemical characteristics). Consequently, there is an important need for robust pharmacokinetic data in wildlife species to ensure optimal therapy for this special group of patients. As part of this review, we identify key aspects that should be considered when estimating dose in species for which there is limited pharmacokinetic information available.

Pharmacists in zoos? A qualitative study investigating the potential for pharmacist involvement in wildlife health care in Aotearoa, New Zealand.

BACKGROUND: The importance of wildlife health has been critically emphasized by the current global pandemic. Pharmacists play a valuable role in the health care of companion animals and livestock; however, their involvement in exotic animal health is largely unexplored. OBJECTIVES: This project consulted with zoo vets in New Zealand and investigated their practices around prescribing and dispensing of medicines to explore the opportunities for the involvement of pharmacists. METHODS: A mixed methods approach was used where data were initially collected through an online survey distributed to 26 veterinarians and animal keepers working in zoos, wildlife parks, and sanctuaries. An optional semistructured interview followed the survey. RESULTS: The facilities surveyed housed New Zealand native animal species and 85% also housed exotic animals. Veterinarians dispensed 75% of medicines at their animal facility, whereas the remaining 25% were dispensed by veterinary nurses. On average, 5-10 medications were dispensed at each animal facility per day. Common medicines dispensed were antibiotics, pain relievers, and antifungals. Most respondents felt that they could benefit from working alongside pharmacists in veterinary care. Compounding, access to medicines and identification of tailored formulations were identified as areas where collaboration would be valued. Limitations in the knowledge of pharmacists in animal medicine were distinguished as an area enhancement to assist in collaborative relationships. CONCLUSIONS: There are opportunities for the skills of pharmacists to be incorporated into the care of animals in zoos and wildlife parks in New Zealand. Strengthening the pharmacist-veterinarian relationship can enhance the health outcomes of animals in animal facilities through this interprofessional interaction.

A Survey of Neonatal Nurses on Mydriatic Regimens Used in Neonatal Retinopathy of Prematurity Eye Examinations.

OBJECTIVE: This study was aimed to determine mydriatic regimen(s) used in neonatal units in Aotearoa, New Zealand (NZ), and Australia and to estimate the frequency of adverse drug events following mydriatic administration in preterm neonates. STUDY DESIGN: A cross-sectional survey was sent to neonatal nursing staff listed in the Australian and New Zealand Neonatal Network contact list. Participants were asked to state what mydriatic regimen they use, and to estimate the frequency of adverse drug events when eye drops were administered for retinopathy of prematurity eye examinations (ROPEE). RESULTS: Thirteen different mydriatic regimens were identified; phenylephrine 2.5% and cyclopentolate 0.5% (1 standard drop of each) was the most commonly used regimen. Two of the regimens exceeded adult doses and five regimens included a mydriatic that is equivalent to an adult dose. Following mydriatic instillation, the three most common adverse effects were apnea, tachycardia, and periorbital pallor. CONCLUSION: Low-concentration single-microdrop regimens are currently in use and resulting in successful ROPEE, yet doses exceeding adult doses are in use throughout Aotearoa, NZ, and Australian units. We know from this dataset that neonates are experiencing unwanted and potentially preventable, adverse effects associated with mydriatics, and every effort should be made to minimize this risk. KEY POINTS: · Thirteen different regimens are in use in Aotearoa, NZ, and Australia.. · Three regimens use doses in excess of adult doses.. · Phenylephrine 2.5% and cyclopentolate 0.5% (one standard drop of each) is the most common regimen.

Influence of formulation and route of administration on ketamine's safety and tolerability: systematic review.

PURPOSE: Ketamine has rapid-onset antidepressant effects in patients with treatment-resistant depression. Common side effects include dissociation (a sense of detachment from reality) and increases in systolic and diastolic blood pressure. The objective of this structured review was to examine the effect of ketamine formulation and route of administration on its pharmacokinetics, safety and tolerability, to identify formulation characteristics and routes of administration that might minimise side effects. METHODS: This was a structured review of published ketamine pharmacokinetics, safety and tolerability data for any ketamine formulation. The ratio of ketamine:norketamine was calculated from reported Cmax values, as a measure of first pass metabolism. The effect of formulation and route of administration on safety was evaluated by measuring mean changes in systolic blood pressure and tolerability by changes in dissociation ratings. Data were correlated using Spearman's method. RESULTS: A total of 41 treatment arms were identified from 21 publications, and included formulation development studies in healthy volunteers, and studies in clinical populations (patients undergoing anaesthesia, or being treated for pain or depression). Ketamine:norketamine ratios were strongly positively correlated with change in dissociation ratings (r = 0.89) and change in blood pressure (r = 0.96), and strongly negatively correlated with ketamine Tmax (r = - 0.87; p < 0.00001 for all). Ketamine Tmax strongly positively correlated with a change in dissociation ratings (r = - 0.96) and change in blood pressure (r = - 0.99; p < 0.00001 for all). CONCLUSION: Ketamine formulations that maximize first pass metabolism and delay Tmax will be better tolerated and safer than formulations which lack those characteristics.

Formulation of a Semisolid Emulsion Containing Leptospermum scoparium Essential Oil and Evaluation of In Vitro Antimicrobial and Antibiofilm Efficacy.

Manuka oil, an essential oil derived from the Leptospermum scoparium, has been traditionally used for wound care and as a topical antibacterial, antifungal, and anti-inflammatory. However, the essential oil is not well retained at mucosal sites, such as the oral cavity, where the benefits of the aforementioned properties could be utilized toward the treatment of persistent biofilms. Within this study, L. scoparium essential oil was incorporated into a semisolid emulsion for improved delivery. The safety profile of L. scoparium essential oil on human gingival fibroblasts was determined via cell viability, cytotoxicity, and caspase activation. The minimal bactericidal concentration of L. scoparium essential oil was determined, and the emulsion's antibiofilm effects visualized using confocal laser scanning microscopy. L. scoparium essential oil demonstrated a lower IC50 (0.02% at 48 h) when compared to the clinical control chlorhexidine (0.002% at 48 h) and displayed lower cumulative cytotoxicity. Higher concentrations of L. scoparium essential oil (≥ 0.1%) at 6 h resulted in higher caspase 3/7 activation, suggesting an apoptotic pathway of cell death. A minimal bactericidal concentration of 0.1% w/w was observed for 6 oral bacteria and 0.01% w/v for Porphyromonas gingivalis. Textural and rheometric analysis indicated increased stability of emulsion with a 1 : 3 ratio of L. scoparium essential oil: Oryza sativa carrier oil. The optimized 5% w/w L. scoparium essential oil emulsion showed increased bactericidal penetrative effects on Streptococci gordonii biofilms compared to oil alone and to chlorhexidine controls. This study has demonstrated the safety, formulation, and antimicrobial activity of L. scoparium essential oil emulsion for potential antibacterial applications at mucosal sites.

Effectiveness of patient decision aids in women considering psychotropic medication use during pregnancy: a literature review.

Women face complicated decisions regarding psychotropic medication use during pregnancy. Patient decision aids (PDAs) could be a valuable tool to assist with decision-making. The objective of this review was to evaluate the effectiveness of PDAs in this population. A systematic search of the literature was conducted using PRISMA guidelines. Three major databases were searched to identify articles published between 2006 and June 2020. Studies were included if they evaluated use of a PDA for women considering medication for mental illness during pregnancy. A total of 4629 titles were returned from the search; however, only three studies met inclusion criteria and were selected for analysis. Two were pilot randomised controlled trials in women considering antidepressant use during pregnancy, and one was a non-randomised study in women considering medication for the treatment of opioid use disorder (OUD). The PDAs had good acceptability across all three studies. The randomised trials assessed knowledge, decisional conflict, depression, and anxiety, with non-significant trends towards reduced decisional conflict and anxiety in the PDA groups. PDAs have the potential to assist women with mental illnesses to make decisions regarding medication use during pregnancy; however, current evidence is too limited to evaluate the effectiveness of PDAs for this population.

Service provision in the wake of a new funding model for community pharmacy.

BACKGROUND: Recently, New Zealand has taken a system wide approach providing the biggest reform to New Zealand community pharmacy for 70 years with the aim of providing more clinically orientated patient centred services through a new funding model. The aim of this study was to understand the types of services offered in New Zealand community pharmacies since introduction of the new funding model, what the barriers are to providing these services. METHOD: A survey of all community pharmacies were undertaken between August, 2014 and February, 2015. Basic descriptive statistics were completed and group comparisons were made using the chi squared test with significance set at p < 0.05. RESULTS: 528 responses were received. Education and advice on prescription and non-prescription medicines were the two top listed services provided. There were no significant differences in service provision between rural and metro based pharmacies. Many pharmacies were considering introducing new patient centred services. Four of the top ten frequently provided services have no public funding attached. Costs and staff availability are the most common barriers to undertake services, more predominantly in patient centred services. CONCLUSION: This study was the first to provide an evaluation of service provision in response to a new funding model for New Zealand Community Pharmacies. A broad range of services are being undertaken in New Zealand community pharmacies including patient-centred services. A number of barriers to service provision were identified. This study provides a baseline for the current levels of service provision upon which future studies can compare to and evaluate any changes in service provision with differing funding models going forward.

Investigation on Secondary Structure Perturbations of Proteins Embedded in Solid Lipid Matrices as a Novel Indicator of their Biological Activity upon In Vitro Release.

Protein biologics are prone to conformational changes during formulation development. Limited methods are available for conformational analysis of proteins in solid state and in the presences of formulation excipients. The aim of this study was to investigate the secondary structures of proteins encased in solid lipid matrices as a novel indicator of their stability upon in vitro release. Model proteins namely catalase and lysozyme were incorporated into lipid namely Precirol® AT05 (glycerol palmitostearate, melting point 58°C) at 30% w/w loading using melting and mixing and wet granulation methods. Attenuated total reflectance (ATR-FTIR) spectroscopy, size-exclusion chromatography (SEC) and biological activity analyses were performed. The information about secondary structure was acquired using second derivative analysis of amide-I band (1600-1700 cm-1). ATR analysis demonstrated interference of lipid spectrum with protein amide-I band which was subsequently subtracted to allow the analysis of the secondary structure. ATR spectra amide-I bands showed shifts peak band positions compared to native protein for matrices prepared using wet granulation. SEC analysis gave evidence of protein aggregation for catalase which was increased using wet granulation. The biological activity of catalase was statistically different from that of control and was affected by the incorporation method and was found to be in alignment with ATR spectral changes and extent of aggregation. In conclusion, ATR spectroscopy could analyze protein secondary structure in lipid matrices provided lipid interference was minimized. The ATR spectral changes and formation of aggregates can indicate the loss in biological activity of protein released from solid lipid matrices.

Effect of gestational age and blood glucose on C-peptide excretion rate and clearance in neonates.

AIMS: The aim of this study was to measure urinary C-peptide concentrations, and then calculate C-peptide clearance (Cl), and excretion rate (UER) in neonates. In addition, the effect of gestational age (GA) and blood glucose levels (BGL) on C-peptide UER were investigated. METHODS: Insulin concentrations in plasma and C-peptide concentrations were measured in plasma and urine, in 20 neonates. Chemiluminescent immunoassays were used for insulin and C-peptide measurements, with urine diluted to 40% with bovine serum albumin 1% in phosphate buffered saline. Urine volume and time of collection were recorded and used to calculate UER and Cl. RESULTS: The mean Cl of C-peptide was 0.309 ± 0.329 mL/min/kg, and UER was 0.0329 ± 0.0342 pmol/min/kg. Correlations between Cl or UER and GA were not significant (P > 0.05). No significant correlation was shown between Cl or UER and BGL (P > 0.05). CONCLUSIONS: Both Cl and UER were highly variable in neonates, but were not correlated with GA. Additionally, BGL did not appear to affect C-peptide UER and Cl. As GA and BGL did not appear to affect Cl and UER, urinary C-peptide may provide a non-invasive method of measuring insulin production in neonates.

Population pharmacokinetic-pharmacodynamic modelling to describe the effects of paracetamol and N-acetylcysteine on the international normalized ratio.

Paracetamol is one of the most common pharmaceutical agents taken in self-poisonings, and can increase the prothrombin time (PT) through liver injury, and in overdose without hepatic injury by reducing functional factor VII. PT is a measure of hepatic injury used to predict and monitor hepatotoxicity, reported as the international normalized ratio (INR). The antidote for paracetamol poisoning, N-acetylcysteine (NAC), has been reported to have an effect on the PT. This analysis included patients from a retrospective case series, a prospective inception cohort of paracetamol and psychotropic (control) overdoses, and a cross-over clinical trial. A population pharmacokinetic-pharmacodynamic model describing the pharmacodynamic effects of paracetamol and NAC on the INR was developed in Phoenix NLME. The dataset included 172 patients; the median age was 22 years (range 13-71 years). A one-compartment model with first-order input and linear disposition best described paracetamol pharmacokinetics. The population mean estimate of the concentration that induced a response halfway between the baseline and maximal pharmacological effect of paracetamol was 1302 µmol/L (242), the maximum effect of paracetamol was 0.534 (202; from baseline) and the maximum effect of NAC was 0.325 (9.03; from baseline). Both paracetamol and NAC contributed a pharmacological effect to the elevation of INR. The estimated paracetamol concentration that induced a response halfway between the baseline and maximal pharmacological effect was within the range of plasma paracetamol values studied, fivefold greater than the maximum therapeutic concentration, suggesting that an elevated INR would not be expected within the therapeutic range. Simulated 24 and 48 g paracetamol overdoses with NAC administration produced INR values (50th percentile) that reached the upper limit of, or exceeded, the reference range.

Population pharmacokinetics of intravenous acetaminophen and its metabolites in major surgical patients.

Intravenous acetaminophen is a commonly used analgesic following surgery. The aims of this study were to determine the population pharmacokinetic profile of intravenous acetaminophen and its metabolites in adult surgical patients and to identify patient characteristics associated with acetaminophen metabolism in the postoperative period. 53 patients were included in the dataset; 28 were men, median age (range) 60 years (33-87), median weight (range) 74 kg (54-129). Patients received 1, 1.5 or 2 g of intravenous acetaminophen every 4-6 h. Plasma and urine samples were collected at various intervals for up to 6 days after surgery. Simultaneous modelling of parent acetaminophen and its metabolites was conducted in Phoenix(®) NLME™ to estimate pharmacokinetic parameters. The population mean estimate (CV%) for central (plasma) volume of distribution of parent acetaminophen (VC) was 13.9 (4.41) L, peripheral (tissue) volume of distribution (VT) was 50.9 (2.96) L, and intercompartmental clearance (Q) was 77.5 (9.29) L/h. The population mean (CV%) metabolic clearances for glucuronidation (CLPG) was 8.92 (3.25) L/h, sulfation (CLPS) was 0.903 (3.47) L/h, and oxidation (CLPO) was 0.533 (7.90) L/h. The population mean (CV%) urinary clearances of parent acetaminophen (CLRP) was 0.137 (5.46) L/h, acetaminophen glucuronide (CLRG) was 3.81 (6.71) L/h, acetaminophen sulfate (CLRS) was 3.13 (4.32) L/h, and acetaminophen cysteine + mercapturate (CLRO) was 3.51 (9.98) L/h. Age was found to be a significant covariate on the formation of acetaminophen glucuronide, and renal function (estimated as creatinine clearance) on the urinary excretion of acetaminophen glucuronide.

The use of lithium as a marker for the retention of liquids in the oral cavity after rinsing.

OBJECTIVE: The aim of this study was to validate the use of lithium as a marker to indicate the retention of simple liquids in the oral cavity and use this to determine how much liquid is retained in the oral cavity following 30 s of rinsing. MATERIALS AND METHODS: This is a validation study in which saliva was spiked with known concentrations of lithium. Twenty healthy participants then rinsed their mouths with either water or a 1 % w/v carboxymethylcellulose (CMC) solution for 30 s before expectorating into a collection cup. Total volume and concentration of lithium in the expectorant were then measured, and the percentage of liquid retained was calculated. RESULTS: The mean amount of liquid retained was 10.4 ± 4.7 % following rinsing with water and 15.3 ± 4.1 % following rinsing with 1 % w/v CMC solution. This difference was significant (p < 0.01). CONCLUSIONS: Lithium was useful as a marker for the retention of liquids in the oral cavity, and a value for the amount of water and 1 % w/v CMC solution remaining in the oral cavity following a 30-s rinse was established. CLINICAL RELEVANCE: The present study quantifies the retention of simple fluids in the oral cavity, validating a technique that may be applied to more complex fluids such as mouth rinses. Further, the application of this method to specific population groups such as those with severe xerostomia may assist in developing effective saliva substitutes.

Ketamine for treatment-resistant major depressive disorder: Double-blind active-controlled crossover study.

BACKGROUND: The N-methyl-D-aspartate antagonist ketamine has rapid onset antidepressant activity in treatment-resistant depression (TRD). AIMS: To evaluate mood rating, safety and tolerability data from patients with TRD treated with ketamine and the psychoactive control fentanyl, as part of a larger study to explore EEG biomarkers associated with mood response. METHODS: We evaluated the efficacy and safety of intramuscular racemic ketamine in 25 patients with TRD, using a double-blind active-controlled randomized crossover design. Ketamine doses were 0.5 and 1 mg/kg, and the psychoactive control was fentanyl 50 mcg, given at weekly intervals. RESULTS/OUTCOMES: Within 1 h of ketamine dosing, patients reported reduced depression and anxiety ratings, which persisted for up to 7 days. A dose-response profile for ketamine was noted for dissociative side effects, adverse events and changes in blood pressure; however, changes in mood ratings were broadly similar for both ketamine doses. Overall, 14/25 patients (56%) were responders (⩾50% reduction at 24 h compared with baseline) for either ketamine dose for the Hospital Anxiety and Depression Scale (HADS), and 18/25 (72%) were responders for the HADS-anxiety scale. After fentanyl, only 1/25 (HADS-depression) and 3/25 (HADS-anxiety) were responders. Ketamine was generally safe and well tolerated in this population. CONCLUSIONS: Our findings add to the literature confirming ketamine's activity against depressive and anxiety symptoms in patients with TRD.

The pharmacokinetic profile of intravenous paracetamol in adult patients undergoing major abdominal surgery.

BACKGROUND: Intravenous (IV) paracetamol is commonly used in the postoperative period for the treatment of mild to moderate pain. The main pathways for paracetamol metabolism are glucuronidation, sulfation, and oxidation, accounting for approximately 55%, 30%, and 10% of urinary metabolites, respectively. The aim of this study was to describe the pharmacokinetics of IV paracetamol and its metabolites in adult patients after major abdominal surgery. METHODS: Twenty patients were given 1 g of paracetamol by IV infusion at induction of anesthesia (Interval 1) and every 6 hours thereafter, with the final dose given at 48-72 hours (Interval 2). Plasma and urine samples were collected for up to 8 hours after infusion for both intervals. The samples were analyzed by high-performance liquid chromatography to determine the amount of paracetamol and its metabolites. The data were modeled in Phoenix WinNonlin using a user-defined ASCII parent-metabolite model with linear disposition, to obtain the estimates for volume of distribution, metabolic and urinary clearance. RESULTS: Mean (95% confidence interval) metabolic clearance to paracetamol glucuronide increased from 0.06 (0.05-0.08) to 0.14 (0.11-0.18) L · h⁻¹ · kg⁻¹, P value <0.001 and urinary clearance increased from 0.08 (0.07-0.09) to 0.14 (0.10-0.17) L · h⁻¹ · kg⁻¹, P value 0.002. The mean (95% confidence interval) volume of distribution of paracetamol increased from 0.17 (0.12-0.21) to 0.43 (0.27-0.59) L · kg⁻¹, P value 0.032. CONCLUSIONS: After major abdominal surgery, there were apparent increases in the metabolic conversion to paracetamol glucuronide and its urinary clearance suggesting potential induction of paracetamol glucuronidation.

AgNP/Alginate Nanocomposite hydrogel for antimicrobial and antibiofilm applications.

The synthesis and specific surface functionalization of antimicrobial silver nanoparticles (AgNPs) and their incorporation into an alginate hydrogel is described. Divalent cation-mediated ionic crosslinking was used to disperse the AgNPs throughout the gel, made possible by -COO- cross-linking sites provided by the surface-enhanced nanoparticles, inspired by the classic egg-box model crosslinking of calcium alginate. An AgNP concentration, 10-20 µg g-1 increased hygrogel elasticity, viscosity, and shear resistance by 45, 30, and 31% respectively. Cryo-TEM revealed evenly distributed AgNP assemblies of discrete AgNPs throughout the gel matrices. FTIR-ATR indicated AgNPs were involved in alginate carboxylate-Ca2+-COO-AgNP crossbridging, which was not achieved through mixing of AgNPs into preformed gels. Live/dead fluorometric assays determined a minimal bactericidal concentration of 25 µg g-1 Ag for 6 microorganisms. Anti-biofilm assays showed species-dependent cell death of 44 -61%, with limited silver ion release of 0.41% and 1.1% after 7 days for Gram positive and negative bacteria, respectively.

Ascending-Dose Study of Controlled-Release Ketamine Tablets in Healthy Volunteers: Pharmacokinetics, Pharmacodynamics, Safety, and Tolerability.

Parenteral ketamine has fast-onset antidepressant and antianxiety effects; however, it causes dissociation, hypertension, and tachycardia shortly after dosing. Ketamine's antidepressant effects may be due to active metabolites rather than to ketamine itself. We hypothesized that oral controlled-release ketamine tablets would improve safety and tolerability compared with injected ketamine by reducing peak ketamine exposures compared with dosing by injection. In this randomized, placebo-controlled ascending-dose study, ketamine doses of 60, 120, or 240 mg or matching placebo (single dose followed by every-12-hours dosing for 5 doses) were given to 24 healthy volunteers. Pharmacokinetics, pharmacodynamics (brain-derived neurotropic factor), adverse events, and vital signs were assessed up to 72 hours. Drug release occurred over ∼10 hours, with most drug substance present as norketamine (∼90%). Area under the concentration-time curve and peak concentration were dose proportional. Elimination half-life was prolonged (7-9 hours) compared with published data from immediate-release oral formulations. There were no changes in blood pressure or heart rate after any dose. Mild dissociation was reported after 240 mg but not lower doses; mean dissociation ratings in this group were minimal (1-2/76). There were no clinically significant changes in ECGs or safety laboratory tests at any time. Compared with injected ketamine, oral controlled-release ketamine tablets did not increase blood pressure or heart rate, and only at doses of 240 mg was dissociation of mild intensity reported. Reducing and delaying ketamine peak concentration by oral dosing with controlled-release ketamine tablets improve this drug's tolerability for patients with depression/anxiety.