Characterisation of cotadutide's dual GLP-1/glucagon receptor agonistic effects on glycaemic control using an in vivo human glucose regulation quantitative systems pharmacology model.

BACKGROUND AND PURPOSE: Cotadutide is a dual GLP-1 and glucagon receptor agonist with balanced agonistic activity at each receptor designed to harness the advantages on promoting liver health, weight loss and glycaemic control. We characterised the effects of cotadutide on glucose, insulin, GLP-1, GIP, and glucagon over time in a quantitative manner using our glucose dynamics systems model (4GI systems model), in combination with clinical data from a multiple ascending dose/Phase 2a (MAD/Ph2a) study in overweight and obese subjects with a history of Type 2 diabetes mellitus (NCT02548585). EXPERIMENTAL APPROACH: The cotadutide PK-4GI systems model was calibrated to clinical data by re-estimating only food related parameters. In vivo cotadutide efficacy was scaled based on in vitro potency. The model was used to explore the effect of weight loss on insulin sensitivity and predict the relative contribution of the GLP-1 and glucagon receptor agonistic effects on glucose. KEY RESULTS: Cotadutide MAD/Ph2a clinical endpoints were successfully predicted. The 4GI model captured a positive effect of weight loss on insulin sensitivity and showed that the stimulating effect of glucagon on glucose production counteracts the GLP-1 receptor-mediated decrease in glucose, resulting in a plateau for glucose decrease around a 200-µg cotadutide dose. CONCLUSION AND IMPLICATIONS: The 4GI quantitative systems pharmacology model was able to predict the clinical effects of cotadutide on glucose, insulin, GLP-1, glucagon and GIP given known in vitro potency. The analyses demonstrated that the quantitative systems pharmacology model, and its successive refinements, will be a valuable tool to support the clinical development of cotadutide and related compounds.

Durable responses to ATR inhibition with ceralasertib in tumors with genomic defects and high inflammation.

BACKGROUNDPhase 1 study of ATRinhibition alone or with radiation therapy (PATRIOT) was a first-in-human phase I study of the oral ATR (ataxia telangiectasia and Rad3-related) inhibitor ceralasertib (AZD6738) in advanced solid tumors.METHODSThe primary objective was safety. Secondary objectives included assessment of antitumor responses and pharmacokinetic (PK) and pharmacodynamic (PD) studies. Sixty-seven patients received 20-240 mg ceralasertib BD continuously or intermittently (14 of a 28-day cycle).RESULTSIntermittent dosing was better tolerated than continuous, which was associated with dose-limiting hematological toxicity. The recommended phase 2 dose of ceralasertib was 160 mg twice daily for 2 weeks in a 4-weekly cycle. Modulation of target and increased DNA damage were identified in tumor and surrogate PD. There were 5 (8%) confirmed partial responses (PRs) (40-240 mg BD), 34 (52%) stable disease (SD), including 1 unconfirmed PR, and 27 (41%) progressive disease. Durable responses were seen in tumors with loss of AT-rich interactive domain-containing protein 1A (ARID1A) and DNA damage-response defects. Treatment-modulated tumor and systemic immune markers and responding tumors were more immune inflamed than nonresponding.CONCLUSIONCeralasertib monotherapy was tolerated at 160 mg BD intermittently and associated with antitumor activity.TRIAL REGISTRATIONClinicaltrials.gov: NCT02223923, EudraCT: 2013-003994-84.FUNDINGCancer Research UK, AstraZeneca, UK Department of Health (National Institute for Health Research), Rosetrees Trust, Experimental Cancer Medicine Centre.

Pharmacokinetics and Safety of Cotadutide, a GLP-1 and Glucagon Receptor Dual Agonist, in Individuals with Renal Impairment: A Single-Dose, Phase I, Bridging Study.

BACKGROUND AND OBJECTIVE: Cotadutide is a balanced glucagon-like peptide-1 and glucagon receptor dual agonist under development for the treatment of non-alcoholic steatohepatitis and type 2 diabetes with chronic kidney disease. We evaluated the pharmacokinetics (PK), safety and immunogenicity of a single dose of cotadutide in individuals with varying degrees of renal impairment. METHODS: In this phase I bridging study, individuals 18-85 years of age, with a body mass index of 17-40 kg/m2 and varying degrees of renal function {end-stage renal disease (ESRD; creatinine clearance [CrCl] < 20 mL/min); severe renal impairment (CrCl ≥ 20 to < 30 mL/min); lower moderate renal impairment (CrCl ≥ 30 to < 44 mL/min); upper moderate renal impairment (CrCl ≥ 45 to < 60 mL/min); normal renal function (CrCl ≥ 90 mL/min)} were treated with a single dose of subcutaneous cotadutide 100 µg under fasted conditions in the lower abdomen. The co-primary endpoints were area under the plasma concentration-time curve from time zero to 48 h (AUC48) and the maximum observed plasma concentration (Cmax) for cotadutide. Safety and immunogenicity were secondary endpoints. This trial is registered with ClinicalTrials.gov (NCT03235375). RESULTS: A total of 37 individuals were enrolled in the study (only three enrolled in the ESRD group, therefore this group was excluded from the primary PK analysis). AUC48 and Cmax values for cotadutide were similar across all renal function groups {severe renal impairment vs. normal renal function: AUC48 geometric mean ratio (GMR) 0.99 (90% confidence interval [CI] 0.76-1.29); lower moderate renal impairment versus normal renal function: AUC48 GMR 1.01 (90% CI 0.79-1.30); upper moderate renal impairment versus normal renal function: AUC48 GMR 1.09 (90% CI 0.82-1.43)}. A sensitivity analysis that combined the ESRD and severe renal impairment groups did not show notable changes in the AUC48 and Cmax GMRs. The incidences of treatment-emergent adverse events (TEAE) ranged from 42.9 to 72.7% across all groups and were mostly mild to moderate in severity. Only one patient had a grade III or worse TEAE during the study period. No positive antidrug antibody results were observed. CONCLUSIONS: These results suggest that the PK and tolerability of cotadutide are unaffected by renal function and that dose adjustments may not be required in individuals with renal impairment.

Efficacy and safety of cotadutide, a dual glucagon-like peptide-1 and glucagon receptor agonist, in a randomized phase 2a study of patients with type 2 diabetes and chronic kidney disease.

AIM: To assess the efficacy, safety and tolerability of cotadutide in patients with type 2 diabetes mellitus and chronic kidney disease. MATERIALS AND METHODS: In this phase 2a study (NCT03550378), patients with body mass index 25-45 kg/m2 , estimated glomerular filtration rate 30-59 ml/min/1.73 m2 and type 2 diabetes [glycated haemoglobin 6.5-10.5% (48-91 mmol/mol)] controlled with insulin and/or oral therapy combination, were randomized 1:1 to once-daily subcutaneous cotadutide (50-300 µg) or placebo for 32 days. The primary endpoint was plasma glucose concentration assessed using a mixed-meal tolerance test. RESULTS: Participants receiving cotadutide (n = 21) had significant reductions in the mixed-meal tolerance test area under the glucose concentration-time curve (-26.71% vs. +3.68%, p < .001), more time in target glucose range on continuous glucose monitoring (+14.79% vs. -21.23%, p = .001) and significant reductions in absolute bodyweight (-3.41 kg vs. -0.13 kg, p < .001) versus placebo (n = 20). In patients with baseline micro- or macroalbuminuria (n = 18), urinary albumin-to-creatinine ratios decreased by 51% at day 32 with cotadutide versus placebo (p = .0504). No statistically significant difference was observed in mean change in estimated glomerular filtration rate between treatments. Mild/moderate adverse events occurred in 71.4% of participants receiving cotadutide and 35.0% receiving placebo. CONCLUSIONS: We established the efficacy of cotadutide in this patient population, with significantly improved postprandial glucose control and reduced bodyweight versus placebo. Reductions in urinary albumin-to-creatinine ratios suggest potential benefits of cotadutide on kidney function, supporting further evaluation in larger, longer-term clinical trials.

A novel integrated QSP model of in vivo human glucose regulation to support the development of a glucagon/GLP-1 dual agonist.

Glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RAs) and dual GLP-1/glucagon receptor agonists improve glycaemic control and cause significant weight loss in patients with type 2 diabetes.1 These effects are driven in part by augmenting glucose-stimulated insulin release (incretin effect), reducing caloric intake and delayed gastric emptying. We developed and externally validated a novel integrated quantitative systems pharmacology (QSP) model to gain quantitative insight into the relative contributions and mechanisms of drugs modulating glucose regulatory pathways. This model (4GI model) incorporates known feedback mechanisms among glucose, GLP-1, glucagon, glucose-dependent insulinotropic peptide (GIP), and insulin after glucose provocation (i.e., food intake) and drug intervention utilizing published nonpharmacological and pharmacological (liraglutide, a GLP-1RA) data. The resulting model accurately describes the aforementioned mechanisms and independently predicts the effects of the GLP-1RAs (dulaglutide and semaglutide) on system dynamics. Therefore, the validated 4GI model represents a quantitative decision-making tool to support the advancement of novel therapeutics and combination strategies modulating these pathways.

Pharmacokinetics, safety, tolerability and efficacy of cotadutide, a glucagon-like peptide-1 and glucagon receptor dual agonist, in phase 1 and 2 trials in overweight or obese participants of Asian descent with or without type 2 diabetes.

AIM: To evaluate the safety and pharmacokinetics of cotadutide, a dual glucagon-like peptide-1 (GLP-1) and glucagon receptor agonist, in overweight Asian participants with or without type 2 diabetes (T2D). MATERIALS AND METHODS: In the phase 1, randomized, blinded, single-ascending dose study, 24 Japanese and eight Chinese healthy adults (body mass index [BMI] 23-40 kg/m2 ) received one subcutaneous dose of cotadutide (50-150 or 100 µg, respectively) or placebo. The primary endpoint was safety. In the phase 2a, randomized, double-blinded, parallel dose-ranging study with forced uptitration, 61 Japanese adults with T2D (BMI 24-40 kg/m2 ; HbA1c 7.0%-10.5%) received cotadutide (100, 200, 300 µg) or placebo for 48 days. Co-primary endpoints were safety/tolerability, change in glucose AUC0-4h and body weight. RESULTS: Significant reductions from baseline to day 48 were observed with cotadutide for glucose AUC0-4h (33.6%-42.1% reduction vs. +2.5% with placebo; 95% CIs: 100 µg -45.7%, -33.7%; 200 µg -35.6%, -23.7%; 300 µg -45.0%, -30.8%; placebo 3.4%, 8.3%) and body weight (1.3%-2.5% decrease vs. +0.8% with placebo; 95% CIs: 100 µg -3.4%, -0.8%; 200 µg -4.7%, -2.0%; 300 µg -4.6%, -2.1%; placebo -2.1%, 0.4%). The most common adverse events with cotadutide were mild gastrointestinal symptoms with no serious adverse events. Increased pulse rate with cotadutide versus placebo is consistent with GLP-1 monoagonists. CONCLUSIONS: Once-daily cotadutide was effective and well tolerated up to 300 µg in overweight Japanese patients with T2D. Further evaluation in Asian populations is warranted.

Developing an injectable co-formulation of two antidiabetic drugs: Excipient impact on peptide aggregation and pharmacokinetic properties.

Combination therapy in Type 2 Diabetes Mellitus is necessary to achieve tight glycaemic control and reduce complication risk. Current treatment plans require patients to take several drugs concomitantly leading to low therapy adherence. This study describes the development and characterisation of a stable parenteral co-formulation of a sodium glucose co-transporter 2 inhibitor (dapagliflozin) and a therapeutic lipidated peptide, using hydroxypropyl-ß-cyclodextrin as an enabling excipient. Using NMR, calorimetry, computational modelling and spectroscopic methods, we show that besides increasing the solubility of dapagliflozin, cyclodextrin prevents self-association of the peptide through interaction with the lipid chain and amino acids prone to aggregation including aromatic groups and ionisable residues. While those interactions cause a dramatic secondary structure change, no impact on potency was seen in vitro. A subcutaneous administration of the co-formulation in rat showed that both drugs reach exposure levels previously shown to be efficacious in clinical mono-therapy studies. Interestingly, a faster absorption rate was observed for the peptide formulated within the cyclodextrin vehicle with respect to the buffer vehicle, which could trigger an earlier onset of action. The cyclodextrin based co-formulation is therefore a promising approach to develop a fixed dose combination of a therapeutic peptide and a small molecule drug for increased patient adherence and better blood glucose control.

Efficacy, Safety, and Mechanistic Insights of Cotadutide, a Dual Receptor Glucagon-Like Peptide-1 and Glucagon Agonist.

CONTEXT: Cotadutide is a dual receptor agonist with balanced glucagon-like peptide-1 and glucagon activity. OBJECTIVE: To evaluate different doses of cotadutide and investigate underlying mechanisms for its glucose-lowering effects. DESIGN/SETTING: Randomized, double-blind, phase 2a study conducted in 2 cohorts at 5 clinical trial sites. PATIENTS: Participants were 65 adult overweight/obese patients with type 2 diabetes mellitus; 63 completed the study; 2 were withdrawn due to AEs. INTERVENTION: Once-daily subcutaneous cotadutide or placebo for 49 days. Doses (50-300 µg) were uptitrated weekly (cohort 1) or biweekly (cohort 2). MAIN OUTCOME MEASURES: Co-primary end points (cohort 1) were percentage changes from baseline to end of treatment in glucose (area under the curve from 0 to 4 hours [AUC0-4h]) post-mixed-meal tolerance test (MMTT) and weight. Exploratory measures included postprandial insulin and gastric emptying time (GET; cohort 2). RESULTS: Patients received cotadutide (cohort 1, n = 26; cohort 2, n = 20) or placebo (cohort 1, n = 13; cohort 2, n = 6). Significant reductions were observed with cotadutide vs placebo in glucose AUC0-4h post MMTT (least squares mean [90% CI], -21.52% [-25.68, -17.37] vs 6.32% [0.45, 12.20]; P < 0.001) and body weight (-3.41% [-4.37, -2.44] vs -0.08% [-1.45, 1.28]; P = 0.002). A significant increase in insulin AUC0-4h post MMTT was observed with cotadutide (19.3 mU.h/L [5.9, 32.6]; P = 0.008) and GET was prolonged on day 43 with cotadutide vs placebo (t½: 117.2 minutes vs -42.9 minutes; P = 0.0392). CONCLUSION: These results suggest that the glucose-lowering effects of cotadutide are mediated by enhanced insulin secretion and delayed gastric emptying. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03244800.

Preclinical development of a high affinity α-synuclein antibody, MEDI1341, that can enter the brain, sequester extracellular α-synuclein and attenuate α-synuclein spreading in vivo.

There are no approved drug therapies that can prevent or slow the progression of Parkinson's disease (PD). Accumulation and aggregation of α-synuclein protein is observed throughout the nervous system in PD. α-Synuclein is a core component of Lewy bodies and neurites that neuropathologically define PD, suggesting that α-synuclein may be a key causative agent in PD. Recent experimental data suggest that PD progression may arise due to spreading of pathological forms of extracellular α-synuclein throughout the brain via a cellular release, uptake and seeding mechanism. We have developed a high affinity α-synuclein antibody, MEDI1341, that can enter the brain, sequester extracellular α-synuclein and attenuate α-synuclein spreading in vivo. MEDI1341 binds both monomeric and aggregated forms of α-synuclein. In vitro, MEDI1341 blocks cell-to-cell transmission of pathologically relevant α-synuclein preformed fibrils (pffs). After intravenous injection into rats and cynomolgus monkeys, MEDI1341 rapidly enters the central nervous system and lowers free extracellular α-synuclein levels in the interstitial fluid (ISF) and cerebrospinal fluid (CSF) compartments. Using a novel lentiviral-based in vivo mouse model of α-synuclein spreading in the brain, we show that treatment with MEDI1341 significantly reduces α-synuclein accumulation and propagation along axons. In this same model, we demonstrate that an effector-null version of the antibody was equally as effective as one with effector function. MEDI1341 is now in Phase 1 human clinical trial testing as a novel treatment for α-synucleinopathies including PD with the aim to slow or halt disease progression.

Randomised, phase 1, dose-finding study of MEDI4166, a PCSK9 antibody and GLP-1 analogue fusion molecule, in overweight or obese patients with type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Cardiovascular disease is the leading cause of morbidity and mortality in people with type 2 diabetes. MEDI4166 is a proprotein convertase subtilisin/kexin type 9 (PCSK9) antibody and glucagon-like peptide-1 (GLP-1) analogue fusion molecule designed to treat patients with type 2 diabetes who are at risk for cardiovascular disease. In this completed, first-in-human study, we evaluated the safety and efficacy of single or multiple doses of MEDI4166 in participants with type 2 diabetes. METHODS: In this phase 1 study that was conducted across 11 clinics in the USA, eligible adults had type 2 diabetes, a BMI of ≥25 kg/m2 to ≤42 kg/m2, and LDL-cholesterol levels ≥1.81 mmol/l. Participants were randomised 3:1 to receive MEDI4166 or placebo using an interactive voice/web response system, which blinded all participants, investigators and study site personnel to the study drug administered. In 'Part A' of the study, five cohorts of participants received a single s.c. injection of MEDI4166 at 10 mg, 30 mg, 100 mg, 200 mg or 400 mg, or placebo. 'Part B' of the study consisted of three cohorts of participants who received an s.c. dose of MEDI4166 once weekly for 5 weeks at 50 mg, 200 mg or 400 mg, or placebo. The primary endpoint in Part A was safety. The co-primary endpoints in Part B were change in LDL-cholesterol levels and area under the plasma glucose concentration-time curve (AUC0-4h) post-mixed-meal tolerance test (MMTT) from baseline to day 36. The pharmacokinetics and immunogenicity of MEDI4166 were also evaluated. RESULTS: MEDI4166 or placebo was administered to n = 30 or n = 10 participants, respectively, in Part A of the study, and n = 48 or n = 15 participants, respectively, in Part B. The incidence of treatment-emergent adverse events (TEAEs) were comparable between MEDI4166 and placebo in both Part A (60% vs 50%) and Part B (79% vs 87%) of the study. Common TEAEs with MEDI4166 included injection-site reactions, diarrhoea and headache; there was no evidence for dose-related increases in TEAEs. In Part B of the study, at all tested doses of MEDI4166, there was a significant decrease in LDL-cholesterol levels vs placebo (least squares mean [95% CI]; MEDI4166 50 mg, -1.25 [-1.66, -0.84]; MEDI4166 200 mg, -1.97 [-2.26, -1.68]; MEDI4166 400 mg, -1.96 [-2.23, -1.70]; placebo, -0.03 [-0.35, 0.28]; all p < 0.0001). However, there were no clinically relevant reductions or significant differences between MEDI4166 vs placebo in glucose AUC0-4h post-MMTT (least squares mean [95% CI]; MEDI4166 50 mg, -10.86 [-17.69, -4.02]; MEDI4166 200 mg, -4.23 [-8.73, 0.28]; MEDI4166 400 mg, -2.59 [-7.14, 1.95]; placebo, -4.84 [-9.95, 0.28]; all p > 0.05). MEDI4166 was associated with a pharmacokinetic profile supportive of weekly dosing and an overall treatment-induced anti-drug antibody-positive rate of 22%. CONCLUSIONS/INTERPRETATION: MEDI4166 was associated with an acceptable tolerability profile and significantly decreased LDL-cholesterol levels in a dose-dependent manner in overweight or obese patients with type 2 diabetes. However, there were no significant reductions in postprandial glucose levels at any dose of MEDI4166. TRIAL REGISTRATION: ClinicalTrials.gov NCT02524782 FUNDING: This study was funded by MedImmune LLC, Gaithersburg, MD, USA.

MEDI0382, a GLP-1 and glucagon receptor dual agonist, in obese or overweight patients with type 2 diabetes: a randomised, controlled, double-blind, ascending dose and phase 2a study.

BACKGROUND: Weight loss is often key in the management of obese or overweight patients with type 2 diabetes, yet few treatments for diabetes achieve clinically meaningful weight loss. We aimed to assess the efficacy, tolerability, and safety of treatment with MEDI0382, a balanced glucagon-like peptide-1 and glucagon receptor dual agonist developed to provide glycaemic control and weight loss, in patients with type 2 diabetes. METHODS: This randomised, placebo-controlled, double-blind, combined multiple-ascending dose (MAD) and phase 2a study was done at 11 study sites (hospitals and contract research organisations) in Germany. We enrolled patients aged 18-65 years with controlled type 2 diabetes (glycated haemoglobin A1c [HbA1c] levels of 6·5-8·5% at screening) and a body-mass index between 27 kg/m2 and 40 kg/m2. An interactive web-response system was used to randomly assign patients to receive MEDI0382 or placebo. Patients were randomly assigned 2:1 in cohorts A-C and 3:1 in cohorts D and E in the MAD portion of the study, and 1:1 in the phase 2a portion. Randomisation was done by a contracted third-party operator who was not involved in the clinical operations of the study. The pharmacists, participants, and study site personnel involved in treating and assessing participants were masked to treatment allocation. Patients received once-daily subcutaneous injections of the study drug at doses of no more than 300 µg for 22 days or less in the MAD portion of the study, and a dose of no more than 200 µg for 41 days or less in the phase 2a portion. The two primary endpoints of the phase 2a portion were the change from baseline to day 41 in glucose area under the curve at 0-4 h (AUC0-4 h) after a mixed-meal tolerance test (MMTT), assessed in all participants who received at least one dose of study drug and whose measurements were taken at baseline and day 41, and change from baseline in bodyweight, assessed in the intention-to-treat (ITT) population. Safety analyses were done in all participants who received any study drug analysed according to the treatment they received. This study is registered with ClinicalTrials.gov, number NCT02548585. FINDINGS: Patients were recruited between Dec 9, 2015, and Feb 24, 2017. 61 patients were randomly assigned to the MAD part of the study (42 to MEDI0382 and 19 to placebo). 51 patients were randomly assigned to the phase 2a part, of whom 25 were randomly assigned to MEDI0382 and 26 to placebo. In the phase 2a study, three patients in the MEDI0382 group and one in the placebo group discontinued, all as a result of adverse events. 22 (88%) patients in the MEDI0382 group and 25 (96%) in the placebo group received at least one dose and had measurements taken at baseline and day 41. Glucose AUC0-4 h post MMTT decreased significantly with MEDI0382 versus placebo (least squares [LS] mean -32·78% [90% CI -36·98 to -28·57] vs -10·16% [-14·10 to -6·21], and the mean difference was -22·62% [-28·40 to -16·85]; p<0·0001). In the ITT population, reduction in bodyweight was significantly greater with MEDI0382 than with placebo (LS mean -3·84 kg [90% CI -4·55 to -3·12] vs -1·70 kg [-2·40 to -1·01] and mean difference of 2·14 kg [-3·13 to -1·31]; p=0·0008). The proportion of patients who had a treatment-emergent adverse event (TEAE) was similar between treatment groups (22 [88%] of 25 in the MEDI0382 group vs 23 [88%] of 26 in the placebo group); gastrointestinal disorders (18 [72%] vs 13 [40%]) and decreased appetite (five [20%] vs none) occurred more frequently with MEDI0382 than placebo. No participants in the MEDI0382 group had a grade 3 or worse TEAE (vs two [8%] in the placebo group). INTERPRETATION: MEDI0382 has the potential to deliver clinically meaningful reductions in blood glucose and bodyweight in obese or overweight individuals with type 2 diabetes. FUNDING: MedImmune.

MEDI0382, a GLP-1/glucagon receptor dual agonist, meets safety and tolerability endpoints in a single-dose, healthy-subject, randomized, Phase 1 study.

AIMS: MEDI0382 is a balanced glucagon-like peptide-1/glucagon receptor dual agonist under development for the treatment of type 2 diabetes mellitus and non-alcoholic steatohepatitis. The primary objective was to assess the safety of MEDI0382 in healthy subjects. METHODS: In this placebo-controlled, double-blind, Phase 1 study, healthy subjects (aged 18-45 years) were randomized (3:1) to receive a single subcutaneous dose of MEDI0382 or placebo after ≥8 h of fasting. The study consisted of six cohorts that received study drug at 5 µg, 10 µg, 30 µg, 100 µg, 150 µg or 300 µg. The primary objective was safety and tolerability. Secondary endpoints included assessments of pharmacokinetics and immunogenicity. All subjects were followed for up to 28 days. RESULTS: A total of 36 subjects received MEDI0382 (n = 6 per cohort) and 12 subjects received placebo (n = 2 per cohort). Treatment-emergent adverse events (TEAEs) occurred more frequently with MEDI0382 vs. placebo, which was mostly due to an increased occurrence at MEDI0382 doses ≥150 µg. All TEAEs were mild or moderate in severity. The most common TEAEs were vomiting, nausea and dizziness. There appeared to be a dose-dependent increase in heart rate with MEDI0382 treatment. MEDI0382 showed linear pharmacokinetic profile (time to maximum plasma concentration: 4.50-9.00 h; elimination half-life: 9.54-12.07 h). No immunogenicity was observed in the study. CONCLUSIONS: In this single-dose, Phase 1 study in healthy subjects, the safety and pharmacokinetic profiles of MEDI0382 support once-daily dosing and further clinical development of MEDI0382.

Monoamine transporter occupancy of a novel triple reuptake inhibitor in baboons and humans using positron emission tomography.

The selection of a therapeutically meaningful dose of a novel pharmaceutical is a crucial step in drug development. Positron emission tomography (PET) allows the in vivo estimation of the relationship between the plasma concentration of a drug and its target occupancy, optimizing dose selection and reducing the time and cost of early development. Triple reuptake inhibitors (TRIs), also referred to as serotonin-norepinephrine-dopamine reuptake inhibitors, enhance monoaminergic neurotransmission by blocking the action of the monoamine transporters, raising extracellular concentrations of those neurotransmitters. GSK1360707 [(1R,6S)-1-(3,4-dichlorophenyl)-6-(methoxymethyl)-4-azabicyclo[4.1.0]heptane] is a novel TRI that until recently was under development for the treatment of major depressive disorder; its development was put on hold for strategic reasons. We present the results of an in vivo assessment of the relationship between plasma exposure and transporter blockade (occupancy). Studies were performed in baboons (Papio anubis) to determine the relationship between plasma concentration and occupancy of brain serotonin reuptake transporter (SERT), dopamine reuptake transporter (DAT), and norepinephrine uptake transporter (NET) using the radioligands [(11)C]DASB [(N,N-dimethyl-2-(2-amino-4-cyanophenylthio) benzylamine], [(11)C]PE2I [N-(3-iodoprop-2E-enyl)-2ß-carbomethoxy-3ß-(4-methylphenyl)nortropane], and [(11)C]2-[(2-methoxyphenoxy)phenylmethyl]morpholine (also known as [(11)C]MRB) and in humans using [(11)C]DASB and [(11)C]PE2I. In P. anubis, plasma concentrations resulting in half-maximal occupancy at SERT, DAT, and NET were 15.16, 15.56, and 0.97 ng/ml, respectively. In humans, the corresponding values for SERT and DAT were 6.80 and 18.00 ng/ml. GSK1360707 dose-dependently blocked the signal of SERT-, DAT-, and NET-selective PET ligands, confirming its penetration across the blood-brain barrier and blockade of all three monoamine transporters in vivo.

New fused benzazepine as selective D3 receptor antagonists. Synthesis and biological evaluation. Part one: [h]-fused tricyclic systems.

The synthesis and SAR of a new series of potent and selective dopamine D(3) receptor antagonists is reported. The introduction of a tricyclic [h]-fused benzazepine moiety on the recently disclosed scaffold of 1,2,4-triazol-3-yl-thiopropyl-tetrahydrobenzazepines is reported. A full rat pharmacokinetic characterization is also reported.

New fused benzazepine as selective D3 receptor antagonists. Synthesis and biological evaluation. Part 2: [g]-fused and hetero-fused systems.

The synthesis and the SAR of a new series of potent and selective dopamine D(3) receptor antagonists is reported. The new scaffolds of the [g]-fused and the hetero-fused tricyclic benzazepine are here reported together with their pharmacokinetic profile.

1,2,4-triazol-3-yl-thiopropyl-tetrahydrobenzazepines: a series of potent and selective dopamine D(3) receptor antagonists.

The discovery of new highly potent and selective dopamine D3 receptor antagonists has recently permitted characterization of the role of the dopamine D3 receptor in a wide range of preclinical animal models. A novel series of 1,2,4-triazol-3-yl-thiopropyl-tetrahydrobenzazepines demonstrating a high level of D3 affinity and selectivity with an excellent pharmacokinetic profile is reported here. In particular, the pyrazolyl derivative 35 showed good oral bioavailability and brain penetration associated with high potency and selectivity in vitro. In vivo characterization of 35 confirmed that this compound blocks the expression of nicotine- and cocaine-conditioned place preference in the rat, prevents nicotine-triggered reinstatement of nicotine-seeking behavior in the rat, reduces oral operant alcohol self-administration in the mouse, increases extracellular levels of acetylcholine in the rat medial prefrontal cortex, and potentiates the amplitude of the relative cerebral blood volume response to d-amphetamine in a regionally specific manner in the rat brain.

Isoindolone derivatives, a new class of 5-HT2C antagonists: synthesis and biological evaluation.

Two independent approaches resulted in the identification of a series of isoindolone derivatives as potent and selective 5-HT2C antagonists. From a Medicinal Chemistry perspective this template was considered interesting as it allowed the incorporation of the carbon-carbon double bond of an earlier dihydropyrrolone series in an aromatic system within a comparatively simple and compact motif. Additionally an in silico screening approach of the corporate database using a 5-HT2C pharmacophore model resulted in the identification of a related structure containing this template. The strategy used to optimise potency at the target receptor and to improve the pharmacokinetic profile is described, resulting in molecules combining high potency with good selectivity and oral bioavailability.

5-HT2C antagonists based on fused heterotricyclic templates: design, synthesis and biological evaluation.

Design, synthesis and properties of a new tricyclic series of selective 5-HT2C receptor antagonists are reported. Conformational analysis of a 2-phenyl-dihydropyrrolone scaffold suggested that ring fusion, locking coplanarity between the rings of this moiety, might be tolerated by the 5-HT2C receptor. An interesting effect of this is the change of the nature of the carbon-carbon double bond of the lactam ring from vinylic to aromatic. The changes were found to result in a favourable profile at both, receptor and in vivo level.

Diaryl substituted pyrrolidinones and pyrrolones as 5-HT2C inhibitors: synthesis and biological evaluation.

Within the continuous quest for the discovery of novel compounds able to treat anxiety and depression, the generation of a pharmacophore model for 5-HT2C receptor antagonists and the discovery of a new class of potent and selective 5-HT2C molecules are reported.

Evaluation of the role of intestinal and liver metabolism in the conversion of two different ester prodrugs of sanfetrinem to the parent drug in vitro and in vivo using different rat tissues and a surgically prepared rat model.

To improve oral absorption of sanfetrinem, a broad-spectrum, beta-lactamase-stable antibiotic, two different ester prodrugs have been selected. Both prodrugs proved to be readily hydrolyzed after absorption before reaching the systemic circulation. The objective of this study was to evaluate the role of intestinal and liver metabolism in the conversion of the two prodrugs into the active compound. In vitro experiments were performed in different rat tissues involved in the absorption process. Moreover data obtained with in vitro experiments have been integrated with data obtained in vivo using a surgically prepared rat model which allows for the measurement of the amount of intact prodrug that overcomes the intestinal mucosa and its presence in the portal vein. Both prodrugs proved to be readily cleaved by jejunum and liver microsomes. The rates of ester hydrolysis with these two tissues were 10- to 30-fold higher than those calculated in intestinal juice at pH 7.4 and about 100-fold higher than in buffer at pH 5.5. These data suggest that both the intestinal wall and liver could play an important role in the conversion of the two prodrugs in active parent compound. In the in vivo experiment, relative to sanfetrinem levels, very low concentrations of intact esters were measured in the portal vein blood, indicating that the two prodrugs are nearly completely hydrolyzed to the active drug by the intestinal wall. In conclusion this study demonstrated that the intestinal epithelium plays a major role in the conversion of the two prodrugs into sanfetrinem. The liver, despite its high esterase activity seems to be only marginally involved.