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1.
Sci Rep ; 14(1): 13537, 2024 06 12.
Article in English | MEDLINE | ID: mdl-38866918

ABSTRACT

The development of interventions targeting reservoirs of Borrelia burgdorferi sensu stricto with acaricide to reduce the density of infected ticks faces numerous challenges imposed by ecological and operational limits. In this study, the pharmacokinetics, efficacy and toxicology of fluralaner were investigated in Mus musculus and Peromyscus leucopus mice, the main reservoir of B. burgdorferi in North America. Fluralaner showed rapid distribution and elimination, leading to fast plasma concentration (Cp) depletion in the first hours after administration followed by a slow elimination rate for several weeks, resulting in a long terminal half-life. Efficacy fell below 100% while Cp (± standard deviation) decreased from 196 ± 54 to 119 ± 62 ng/mL. These experimental results were then used in simulations of fluralaner treatment for a duration equivalent to the active period of Ixodes scapularis larvae and nymphs. Simulations showed that doses as low as 10 mg/kg have the potential to protect P. leucopus against infestation for a full I. scapularis active season if administered at least once every 7 days. This study shows that investigating the pharmacology of candidate acaricides in combination with pharmacokinetic simulations can provide important information to support the development of effective interventions targeting ecological reservoirs of Lyme disease. It therefore represents a critical step that may help surpass limits inherent to the development of these interventions.


Subject(s)
Acaricides , Borrelia burgdorferi , Disease Reservoirs , Ixodes , Lyme Disease , Peromyscus , Animals , Lyme Disease/drug therapy , Mice , Ixodes/microbiology , Ixodes/drug effects , Disease Reservoirs/microbiology , Peromyscus/microbiology , Acaricides/pharmacokinetics , Acaricides/pharmacology , Borrelia burgdorferi/drug effects , Isoxazoles/pharmacokinetics , Female
2.
Poult Sci ; 103(7): 103843, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38806001

ABSTRACT

The demand for the use of fluralaner in an extra label manner is increasing due to lack of efficacious treatment to combat mites and bed bugs in the poultry industry in the United States. Fluralaner residue data in eggs is lacking and residues might cause risks to human health. The present study aimed to determine the depletion profiles of fluralaner in eggs and estimate the drug withdrawal interval in whole eggs by adopting the US Food and Drug administration tolerance limit method with single intravenous (0.5 mg/kg) or transdermal administration (average 58.7 mg/kg) in healthy shaver hens. Hens were treated intravenously or trans-dermally with fluralaner. The eggs were collected daily for 28 d for intravenous treated and for 40 d from the transdermal route group. Fluralaner concentrations in yolk and albumen were determined by mass spectrometry. The greater percentage of fluralaner was observed in yolk when compared to the albumen for both administration routes. Noncompartmental analysis was used to calculate the pharmacokinetic parameters in yolk, albumen and whole egg. The longest apparent half-life confirmed in yolk was 3.7 d for intravenous and 14.3 d for the transdermal route. The withdrawal intervals in whole egg for fluralaner following the intravenous and transdermal administration were 7 d and 81 d, respectively, with maximum residue limits (1.3 µg/g) at 13 d and 171 d, respectively, based on the limit of quantification (0.4 µg/g) from the analytical assay reported by EMA and APVMA.


Subject(s)
Administration, Cutaneous , Chickens , Drug Residues , Isoxazoles , Animals , Isoxazoles/administration & dosage , Isoxazoles/pharmacokinetics , Female , Drug Residues/chemistry , Drug Residues/analysis , Ovum/chemistry , Eggs/analysis , Acaricides/administration & dosage , Acaricides/pharmacokinetics , Injections, Intravenous/veterinary , Pesticide Residues/analysis
3.
Schizophr Res ; 264: 122-129, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38128343

ABSTRACT

BACKGROUND: Several studies have indicated that the plasma concentration of risperidone increases 3-5-fold during the acute-phase reaction (APR) of inflammation or infection. Psychiatric symptoms are present or deteriorate when the dose is lowered; thus, the complex effects of inflammation on the pharmacokinetics of risperidone need to be examined. METHODS: We established a APR model in rabbits induced by lipopolysaccharide (LPS) and studied the effect of APR on pharmacokinetics, distribution and disposition of risperidone in vivo and in vitro. RESULTS: Following intramuscular administration, the plasma exposures for risperidone and its active metabolite (9-hydroxyrisperidone) were increased approximately 6-fold on day 2 of inflammation. The exposure values did not change between day 2 and 5 of inflammation, nor did the metabolite-to-parent ratio before and during inflammation. Following oral administration, the increase of risperidone exposure was twice as high as that following intramuscular administration during APR. However, the concentration of risperidone and 9-hydroxyrisperidone in brain tissue was similar between the inflammatory and control groups. Moreover, the plasma protein binding (PPB) of risperidone and 9-hydroxyrisperidone associated with inflammation were all increased to >99 %. In addition, risperidone and 9-hydroxyrisperidone were not substrates of the key transporters, OATP1B3, OCT2, OAT3, MATE-1, or MATE-2 K. The expression of progesterone X receptor and P-glycoprotein was inhibited by LPS. CONCLUSION: During APR, reduced expression of P-glycoprotein and increased PPB were responsible for increased exposure in plasma, while maintaining stable concentrations in the brain, and risperidone does not need to be dose-adjusted so as to achieve psychopharmacological outcomes.


Subject(s)
Antipsychotic Agents , Risperidone , Animals , Rabbits , Paliperidone Palmitate , Isoxazoles/pharmacokinetics , Pyrimidines/pharmacokinetics , Acute-Phase Reaction/chemically induced , Lipopolysaccharides , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , ATP Binding Cassette Transporter, Subfamily B
4.
J Med Chem ; 65(4): 3539-3562, 2022 02 24.
Article in English | MEDLINE | ID: mdl-35077170

ABSTRACT

The sphingosine-1-phosphate-1 (S1P1) receptor agonists have great potential for the treatment of multiple sclerosis (MS) because they can inhibit lymphocyte egress through receptor internalization. We designed and synthesized triazole and isoxazoline derivatives to discover a novel S1P1 agonist for MS treatment. Of the two scaffolds, the isoxazoline derivative was determined to have excellent in vitro efficacy and drug-like properties. Among them, compound 21l was found to have superior drug-like properties as well as excellent in vitro efficacies (EC50 = 7.03 nM in ß-arrestin recruitment and EC50 = 11.8 nM in internalization). We also confirmed that 21l effectively inhibited lymphocyte egress in the peripheral lymphocyte count test and significantly improved the clinical score in the experimental autoimmune encephalitis MS mouse model.


Subject(s)
Multiple Sclerosis/drug therapy , Sphingosine-1-Phosphate Receptors/antagonists & inhibitors , Animals , Dogs , Drug Design , Encephalomyelitis, Autoimmune, Experimental/drug therapy , Heart Rate/drug effects , Humans , Isoxazoles/chemical synthesis , Isoxazoles/pharmacokinetics , Isoxazoles/pharmacology , Lymphocyte Count , Lymphocytes/drug effects , Male , Mice , Rats , Structure-Activity Relationship , Triazoles/chemical synthesis , Triazoles/pharmacokinetics , Triazoles/pharmacology , beta-Arrestins/drug effects
5.
Bioorg Med Chem Lett ; 49: 128294, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34333139

ABSTRACT

A library of new 3-phenylisoxazolo[5,4-d]pyrimidines (8-10) was designed based on a scaffold hybridization technique incorporating the important pharmacophoric features of 4-aminopyrimidine and phenyl isoxazole scaffold which is renowned for its BET inhibition activity. The designed molecules were synthesized and evaluated with the NCI-60 cell line panel. Examination by NCI-60 cell lines at single-dose and the five-dose study showed that compound 10h exhibited promising growth inhibitory effects with GI50 values on various cancer cell lines such as HCT-15 (Colon Cancer)-0.0221 µM, MDA-MB-435 (Melanoma) - 0.0318 µM, SNB-75(CNS Cancer)-0.0263 µM, and MCF7 (Breast Cancer)-0.0372 µM. Further studies to know the mechanism of action of 10h based on the phase-contrast microscopic evaluation, DAPI, acridine orange/ethidium bromide (AO/EB) staining, and annexin V-FITC assays revealed that elevation in the intracellular ROS leads to alteration in mitochondrial membrane potential which in turn induced the apoptosis in BT-474 cancer cells, which could be the plausible mechanism of action for compound 10h.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Isoxazoles/pharmacology , Pyrimidines/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Cell Proliferation/drug effects , Dogs , Drug Design , Drug Screening Assays, Antitumor , Humans , Isoxazoles/chemical synthesis , Isoxazoles/pharmacokinetics , Madin Darby Canine Kidney Cells , Molecular Structure , Pyrimidines/chemical synthesis , Pyrimidines/pharmacokinetics , Reactive Oxygen Species/metabolism , Structure-Activity Relationship
6.
Drug Metab Dispos ; 49(7): 548-562, 2021 07.
Article in English | MEDLINE | ID: mdl-33952610

ABSTRACT

Tropifexor (NVP-LJN452) is a highly potent, selective, nonsteroidal, non-bile acid farnesoid X receptor agonist for the treatment of nonalcoholic steatohepatitis. Its absorption, metabolism, and excretion were studied after a 1-mg oral dose of [14C]tropifexor was given to four healthy male subjects. Mass balance was achieved with ∼94% of the administered dose recovered in excreta through a 312-hour collection period. Fecal excretion of tropifexor-related radioactivity played a major role (∼65% of the total dose). Tropifexor reached a maximum blood concentration (Cmax) of 33.5 ng/ml with a median time to reach Cmax of 4 hours and was eliminated with a plasma elimination half-life of 13.5 hours. Unchanged tropifexor was the principal drug-related component found in plasma (∼92% of total radioactivity). Two minor oxidative metabolites, M11.6 and M22.4, were observed in circulation. Tropifexor was eliminated predominantly via metabolism with >68% of the dose recovered as metabolites in excreta. Oxidative metabolism appeared to be the major clearance pathway of tropifexor. Metabolites containing multiple oxidative modifications and combined oxidation and glucuronidation were also observed in human excreta. The involvement of direct glucuronidation could not be ruled out based on previous in vitro and nonclinical in vivo studies indicating its contribution to tropifexor clearance. The relative contribution of the oxidation and glucuronidation pathways appeared to be dose-dependent upon further in vitro investigation. Because of these complexities and the instability of glucuronide metabolites in the gastrointestinal tract, the contribution of glucuronidation remained undefined in this study. SIGNIFICANCE STATEMENT: Tropifexor was found to be primarily cleared from the human body via oxidative metabolism. In vitro metabolism experiments revealed that the relative contribution of oxidation and glucuronidation was concentration-dependent, with glucuronidation as the predominant pathway at higher concentrations and the oxidative process becoming more important at lower concentrations near clinical exposure range. The body of work demonstrated the importance of carefully designed in vivo and in vitro experiments for better understanding of disposition processes during drug development.


Subject(s)
Benzothiazoles/pharmacokinetics , Isoxazoles/pharmacokinetics , Administration, Oral , Adolescent , Adult , Benzothiazoles/administration & dosage , Gastrointestinal Absorption , Healthy Volunteers , Humans , Isoxazoles/administration & dosage , Male , Metabolic Clearance Rate , Middle Aged , Young Adult
7.
Br J Cancer ; 125(4): 520-527, 2021 08.
Article in English | MEDLINE | ID: mdl-34040174

ABSTRACT

BACKGROUND: Berzosertib (formerly M6620, VX-970) is a highly potent and selective, first-in-class ataxia telangiectasia-mutated and Rad3-related protein kinase (ATR) inhibitor. We assessed the safety, tolerability, pharmacokinetics, and preliminary efficacy of berzosertib plus cisplatin. METHODS: Adult patients with advanced solid tumours refractory or resistant to standard of care therapies received ascending doses of cisplatin (day 1) and berzosertib (days 2 and 9) every 3 weeks (Q3W). RESULTS: Thirty-one patients received berzosertib (90-210 mg/m2) and cisplatin (40-75 mg/m2) across seven dose levels. The most common grade ≥3 treatment-emergent adverse events were neutropenia (20.0%) and anaemia (16.7%). There were two dose-limiting toxicities: a grade 3 hypersensitivity reaction and a grade 3 increase in alanine aminotransferase. Berzosertib 140 mg/m2 (days 2 and 9) and cisplatin 75 mg/m2 (day 1) Q3W was determined as the recommended Phase 2 dose. Cisplatin had no apparent effect on berzosertib pharmacokinetics. Of the 31 patients, four achieved a partial response (two confirmed and two unconfirmed) despite having previously experienced disease progression following platinum-based chemotherapy. CONCLUSIONS: Berzosertib plus cisplatin is well tolerated and shows preliminary clinical activity in patients with advanced solid tumours, warranting further evaluation in a Phase 2 setting. CLINICAL TRIALS IDENTIFIER: NCT02157792.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cisplatin/administration & dosage , Isoxazoles/administration & dosage , Neoplasms/drug therapy , Pyrazines/administration & dosage , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/adverse effects , Cisplatin/pharmacokinetics , Drug Administration Schedule , Drug Resistance, Neoplasm/drug effects , Female , Humans , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Male , Middle Aged , Pyrazines/adverse effects , Pyrazines/pharmacokinetics , Treatment Outcome
8.
Br J Cancer ; 125(4): 510-519, 2021 08.
Article in English | MEDLINE | ID: mdl-34040175

ABSTRACT

BACKGROUND: Berzosertib (formerly M6620, VX-970) is a highly potent and selective, first-in-class inhibitor of ataxia telangiectasia and Rad3-related protein kinase (ATR). We assessed multiple ascending doses of berzosertib + gemcitabine ± cisplatin in patients with resistant/refractory advanced solid tumours. METHODS: We evaluated the safety, tolerability, pharmacokinetics (PK) and preliminary efficacy of intravenous berzosertib + gemcitabine ± cisplatin using a standard 3 + 3 dose-escalation design. The starting doses were berzosertib 18 mg/m2, gemcitabine 875 mg/m2 and cisplatin 60 mg/m2. RESULTS: Fifty-two patients received berzosertib + gemcitabine and eight received berzosertib + gemcitabine + cisplatin. Four patients receiving berzosertib + gemcitabine had a total of seven dose-limiting toxicities (DLTs) and three receiving berzosertib + gemcitabine + cisplatin had a total of three DLTs. Berzosertib 210 mg/m2 (days 2 and 9) + gemcitabine 1000 mg/m2 (days 1 and 8) Q3W was established as the recommended Phase 2 dose (RP2D); no RP2D was determined for berzosertib + gemcitabine + cisplatin. Neither gemcitabine nor cisplatin affected berzosertib PK. Most patients in both arms achieved a best response of either partial response or stable disease. CONCLUSIONS: Berzosertib + gemcitabine was well tolerated in patients with advanced solid tumours and showed preliminary efficacy signs. CLINICAL TRIAL IDENTIFIER: NCT02157792.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Cisplatin/administration & dosage , Deoxycytidine/analogs & derivatives , Isoxazoles/administration & dosage , Neoplasms/drug therapy , Pyrazines/administration & dosage , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Cisplatin/adverse effects , Cisplatin/pharmacokinetics , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Deoxycytidine/pharmacokinetics , Drug Administration Schedule , Female , Humans , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Male , Middle Aged , Pyrazines/adverse effects , Pyrazines/pharmacokinetics , Survival Analysis , Treatment Outcome , Gemcitabine
9.
Int J Infect Dis ; 105: 688-694, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33684562

ABSTRACT

BACKGROUND: Cycloserine, or its structural analogue terizidone, has been associated with neuropsychiatric toxicity (psychosis, depression, and neuropathy). Prospective clinical data on the incidence of and risk factors for neuropsychiatric toxicity in TB patients treated with cycloserine are limited. METHODS: A prospective evaluation of neuropsychiatric toxicity was performed using validated screening tools in patients with multidrug-resistant tuberculosis treated with terizidone. Cox proportional hazard modelling was performed to explore the effects of clinical variables and measures of cycloserine pharmacokinetics in plasma. RESULTS: A total 144 participants were recruited: 86 were male and 58 were female; their median age was 35.7 years and 91 (63%) were HIV-infected. Fifty-five (38%) participants developed at least one neuropsychiatric event (30 cases per 100 person-months): 50 (35%) neuropathy, 14 (10%) depression, and 11 (8%) psychosis. Neuropathy was independently associated with cycloserine clearance ((adjusted hazard ratio 0.34 (aHR), P = 0.03)) and high-dose pyridoxine (200 mg vs 150 mg daily, aHR: 2.79, P = 0.01). CONCLUSIONS: A high incidence of early neuropsychiatric toxicity was observed in this cohort of patients treated with terizidone. Cycloserine clearance and higher doses of pyridoxine are associated with incident or worsening peripheral neuropathy.


Subject(s)
Antibiotics, Antitubercular/adverse effects , Antibiotics, Antitubercular/pharmacokinetics , Cycloserine/adverse effects , Cycloserine/pharmacokinetics , Tuberculosis, Multidrug-Resistant/drug therapy , Adult , Antibiotics, Antitubercular/administration & dosage , Cycloserine/administration & dosage , Depression/chemically induced , Female , HIV Infections/drug therapy , Humans , Incidence , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Male , Middle Aged , Oxazolidinones/adverse effects , Oxazolidinones/pharmacokinetics , Peripheral Nervous System Diseases/chemically induced , Prospective Studies , Psychoses, Substance-Induced/epidemiology , Risk Factors , Tuberculosis, Multidrug-Resistant/epidemiology
10.
Parasit Vectors ; 14(1): 18, 2021 Jan 06.
Article in English | MEDLINE | ID: mdl-33407820

ABSTRACT

BACKGROUND: Sarcoptic mange causes significant animal welfare and occasional conservation concerns for bare-nosed wombats (Vombatus ursinus) throughout their range. To date, in situ chemotherapeutic interventions have involved macrocytic lactones, but their short duration of action and need for frequent re-administration has limited treatment success. Fluralaner (Bravecto®; MSD Animal Health), a novel isoxazoline class ectoparasiticide, has several advantageous properties that may overcome such limitations. METHODS: Fluralaner was administered topically at 25 mg/kg (n = 5) and 85 mg/kg (n = 2) to healthy captive bare-nosed wombats. Safety was assessed over 12 weeks by clinical observation and monitoring of haematological and biochemical parameters. Fluralaner plasma pharmacokinetics were quantified using ultra-performance liquid chromatography and tandem mass spectrometry. Efficacy was evaluated through clinical assessment of response to treatment, including mange and body condition scoring, for 15 weeks after topical administration of 25 mg/kg fluralaner to sarcoptic mange-affected wild bare-nosed wombats (n = 3). Duration of action was determined through analysis of pharmacokinetic parameters and visual inspection of study subjects for ticks during the monitoring period. Methods for diluting fluralaner to enable 'pour-on' application were compared, and an economic and treatment effort analysis of fluralaner relative to moxidectin was undertaken. RESULTS: No deleterious health impacts were detected following fluralaner administration. Fluralaner was absorbed and remained quantifiable in plasma throughout the monitoring period. For the 25 mg/kg and 85 mg/kg treatment groups, the respective means for maximum recorded plasma concentrations (Cmax) were 6.2 and 16.4 ng/ml; for maximum recorded times to Cmax, 3.0 and 37.5 days; and for plasma elimination half-lives, 40.1 and 166.5 days. Clinical resolution of sarcoptic mange was observed in all study animals within 3-4 weeks of treatment, and all wombats remained tick-free for 15 weeks. A suitable product for diluting fluralaner into a 'pour-on' was found. Treatment costs were competitive, and predicted treatment effort was substantially lower relative to moxidectin. CONCLUSIONS: Fluralaner appears to be a safe and efficacious treatment for sarcoptic mange in the bare-nosed wombat, with a single dose lasting over 1-3 months. It has economic and treatment-effort-related advantages over moxidectin, the most commonly used alternative. We recommend a dose of 25 mg/kg fluralaner and, based on the conservative assumption that at least 50% of a dose makes dermal contact, Bravecto Spot-On for Large Dogs as the most appropriate formulation for adult bare-nosed wombats.


Subject(s)
Isoxazoles , Marsupialia/parasitology , Scabies/drug therapy , Administration, Topical , Animals , Animals, Wild/parasitology , Conservation of Natural Resources , Endangered Species , Insecticides/administration & dosage , Insecticides/adverse effects , Insecticides/pharmacokinetics , Insecticides/therapeutic use , Isoxazoles/administration & dosage , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Isoxazoles/therapeutic use , Sarcoptes scabiei/drug effects , Scabies/veterinary , Tasmania
11.
Cancer Chemother Pharmacol ; 87(2): 185-196, 2021 02.
Article in English | MEDLINE | ID: mdl-33145616

ABSTRACT

PURPOSE: Berzosertib (formerly M6620) is the first-in-class inhibitor of ataxia-telangiectasia and Rad3-related protein, a key component of the DNA damage response, and being developed in combination with chemotherapy for the treatment of patients with advanced cancers. The objectives of this analysis were to characterize the pharmacokinetics (PK) of berzosertib across multiple studies and parts, estimate inter-individual variability, and identify covariates that could explain such variability. METHODS: A population PK analysis was performed using the combined dataset from two phase I clinical studies (NCT02157792, EudraCT 2013-005100-34) in patients with advanced cancers receiving an intravenous infusion of berzosertib alone or in combination with chemotherapy. The analysis included data from 240 patients across 11 dose levels (18-480 mg/m2). Plasma concentration data were modeled with a non-linear mixed-effect approach and clinical covariates were evaluated. RESULTS: PK data were best described by a two-compartment linear model. For a typical patient, the estimated clearance (CL) and intercompartmental CL were 65 L/h and 295 L/h, respectively, with central and peripheral volumes estimated to be 118 L and 1030 L, respectively. Several intrinsic factors were found to influence berzosertib PK, but none were considered clinically meaningful due to a very limited effect. Model simulations indicated that concentrations of berzosertib exceeded p-Chk1 (proximal pharmacodynamic biomarker) IC50 at recommended phase II doses in combination with carboplatin, cisplatin, and gemcitabine. CONCLUSIONS: There was no evidence of a clinically significant PK interaction between berzosertib and evaluated chemo-combinations. The covariate analysis did not highlight any need for dosing adjustments in the population studied to date. CLINICAL TRIAL INFORMATION: NCT02157792, EudraCT 2013-005100-34.


Subject(s)
Isoxazoles/pharmacokinetics , Models, Biological , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacokinetics , Pyrazines/pharmacokinetics , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Ataxia Telangiectasia Mutated Proteins/antagonists & inhibitors , Dose-Response Relationship, Drug , Female , Humans , Infusions, Intravenous , Inhibitory Concentration 50 , Isoxazoles/administration & dosage , Male , Middle Aged , Neoplasms/pathology , Protein Kinase Inhibitors/administration & dosage , Pyrazines/administration & dosage
12.
Eur J Med Chem ; 209: 112910, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33049605

ABSTRACT

Farnesoid X receptor (FXR) agonists are emerging as potential therapeutics for the treatment of various metabolic diseases, as they display multiple effects on bile acid, lipid, and glucose homeostasis. Although the steroidal obeticholic acid, a full FXR agonist, was recently approved, several side effects probably due to insufficient pharmacological selectivity impede its further clinical application. Activating FXR in a partial manner is therefore crucial in the development of novel FXR modulators. Our efforts focusing on isoxazole-type FXR agonists, common nonsteroidal agonists for FXR, led to the discovery a series of novel FXR agonists bearing aryl urea moieties through structural simplification of LJN452 (phase 2). Encouragingly, compound 11k was discovered as a potent FXR agonist which exhibited similar FXR agonism potency but lower maximum efficacy compared to full agonists GW4064 and LJN452 in cell-based FXR transactivation assay. Extensive in vitro evaluation further confirmed partial efficacy of 11k in cellular FXR-dependent gene modulation, and revealed its lipid-reducing activity. More importantly, orally administration of 11k in mice exhibited desirable pharmacokinetic characters resulting in promising in vivo FXR agonistic activity.


Subject(s)
Isoxazoles/chemical synthesis , Metabolic Diseases/drug therapy , Receptors, Cytoplasmic and Nuclear/agonists , Administration, Oral , Animals , Benzothiazoles/pharmacology , Drug Evaluation, Preclinical , Gene Expression Regulation/drug effects , Hep G2 Cells , Humans , Isoxazoles/administration & dosage , Isoxazoles/pharmacokinetics , Isoxazoles/pharmacology , Lipids/chemistry , Male , Mice , Mice, Inbred C57BL , Molecular Docking Simulation , Protein Binding , Structure-Activity Relationship
13.
Biomed Res Int ; 2020: 1563874, 2020.
Article in English | MEDLINE | ID: mdl-32832543

ABSTRACT

A sensitive and reliable ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was developed for the simultaneous determination of parecoxib and its metabolite valdecoxib in beagles. The effects of dexmedetomidine on the pharmacokinetics of parecoxib and valdecoxib in beagles were studied. The plasma was precipitated by acetonitrile, and the two analytes were separated on an Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 µm); the mobile phase was acetonitrile and 0.1% formic acid with gradient mode, and the flow rate was 0.4 mL/min. In the negative ion mode, the two analytes and internal standard (IS) were monitored by multiple reaction monitoring (MRM), and the mass transition pairs were as follows: m/z 369.1 → 119.1 for parecoxib, m/z 313.0 → 118.0 for valdecoxib, and m/z 380.0 → 316.0 for celecoxib (IS). Six beagles were designed as a double cycle self-control experiment. In the first cycle, after intramuscular injection of parecoxib 1.33 mg/kg, 1.0 mL blood samples were collected at different times (group A). In the second cycle, the same six beagles were intravenously injected with 2 µg/kg dexmedetomidine for 7 days after one week of washing period. On day 7, after intravenous injection of 2 µg/kg dexmedetomidine for 0.5 hours, 6 beagle dogs were intramuscularly injected with 1.33 mg/kg parecoxib, and blood samples were collected at different time points (group A). The concentration of parecoxib and valdecoxib was detected by UPLC-MS/MS, and the main pharmacokinetic parameters were calculated by DAS 2.0 software. Under the experimental conditions, the method has a good linear relationship for both analytes. The interday and intraday precision was less than 8.07%; the accuracy values were from -1.20% to 2.76%. C max of parecoxib in group A and group B was 2148.59 ± 406.13 ng/mL and 2100.49 ± 356.94 ng/mL, t 1/2 was 0.85 ± 0.36 h and 0.85 ± 0.36 h, and AUC(0-t) was 2429.96 ± 323.22 ng·h/mL and 2506.38 ± 544.83 ng·h/mL, respectively. C max of valdecoxib in group A and group B was 2059.15 ± 281.86 ng/mL and 2837.39 ± 276.78 ng/mL, t 1/2 was 2.44 ± 1.55 h and 2.91 ± 1.27 h, and AUC(0-t) was 4971.61 ± 696.56 ng·h/mL and 6770.65 ± 453.25 ng·h/mL, respectively. There was no significant change in the pharmacokinetics of parecoxib in groups A and B. C max and AUC(0 - ∞) of valdecoxib in group A were 37.79% and 36.19% higher than those in group B, respectively, and t 1/2 was increased from 2.44 h to 2.91 h. V z /F and CL z /F were correspondingly reduced, respectively. The developed UPLC-MS/MS method for simultaneous determination of parecoxib and valdecoxib in beagle plasma was specific, accurate, rapid, and suitable for the pharmacokinetics and drug-drug interactions of parecoxib and valdecoxib. Dexmedetomidine can inhibit the metabolism of valdecoxib in beagles and increase the exposure of valdecoxib, but it does not affect the pharmacokinetics of parecoxib.


Subject(s)
Dexmedetomidine , Isoxazoles/pharmacokinetics , Sulfonamides/pharmacokinetics , Administration, Oral , Animals , Chromatography, High Pressure Liquid , Dexmedetomidine/pharmacokinetics , Dexmedetomidine/pharmacology , Dogs , Isoxazoles/pharmacology , Tandem Mass Spectrometry
14.
Bioorg Med Chem Lett ; 30(19): 127425, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32717372

ABSTRACT

Pharmacological reactivation of the γ-globin gene for the production of fetal hemoglobin (HbF) is a promising approach for the management of ß-thalassemia and sickle cell disease (SCD). We conducted a phenotypic screen in human erythroid progenitor cells to identify molecules that could induce HbF, which resulted in identification of the hit compound 1. Exploration of structure-activity relationships and optimization of ADME properties led to 2-azaspiro[3.3]heptane derivative 18, which is more rigid and has a unique structure. In vivo using cynomolgus monkeys, compound 18 induced a significant dose-dependent increase in globin switching, with developable properties. Moreover, compound 18 showed no genotoxic effects and was much safer than hydroxyurea. These findings could facilitate the development of effective new therapies for the treatment of ß-hemoglobinopathies, including SCD.


Subject(s)
Azetidines/pharmacology , Erythroid Precursor Cells/drug effects , Fetal Hemoglobin/metabolism , Spiro Compounds/pharmacology , Animals , Azetidines/chemical synthesis , Azetidines/pharmacokinetics , Drug Design , Drug Stability , Gene Expression Regulation/drug effects , Humans , Isoxazoles/chemical synthesis , Isoxazoles/pharmacokinetics , Isoxazoles/pharmacology , Macaca fascicularis , Microsomes, Liver/metabolism , Molecular Structure , Spiro Compounds/chemical synthesis , Spiro Compounds/pharmacokinetics , Structure-Activity Relationship
15.
J Clin Oncol ; 38(27): 3195-3204, 2020 09 20.
Article in English | MEDLINE | ID: mdl-32568634

ABSTRACT

PURPOSE: Preclinical studies demonstrated that ATR inhibition can exploit synthetic lethality (eg, in cancer cells with impaired compensatory DNA damage responses through ATM loss) as monotherapy and combined with DNA-damaging drugs such as carboplatin. PATIENTS AND METHODS: This phase I trial assessed the ATR inhibitor M6620 (VX-970) as monotherapy (once or twice weekly) and combined with carboplatin (carboplatin on day 1 and M6620 on days 2 and 9 in 21-day cycles). Primary objectives were safety, tolerability, and maximum tolerated dose; secondary objectives included pharmacokinetics and antitumor activity; exploratory objectives included pharmacodynamics in timed paired tumor biopsies. RESULTS: Forty patients were enrolled; 17 received M6620 monotherapy, which was safe and well tolerated. The recommended phase II dose (RP2D) for once- or twice-weekly administration was 240 mg/m2. A patient with metastatic colorectal cancer harboring molecular aberrations, including ATM loss and an ARID1A mutation, achieved RECISTv1.1 complete response and maintained this response, with a progression-free survival of 29 months at last assessment. Twenty-three patients received M6620 with carboplatin, with mechanism-based hematologic toxicities at higher doses, requiring dose delays and reductions. The RP2D for combination therapy was M6620 90 mg/m2 with carboplatin AUC5. A patient with advanced germline BRCA1 ovarian cancer achieved RECISTv1.1 partial response and Gynecologic Cancer Intergroup CA125 response despite being platinum refractory and PARP inhibitor resistant. An additional 15 patients had RECISTv1.1 stable disease as best response. Pharmacokinetics were dose proportional and exceeded preclinical efficacious levels. Pharmacodynamic studies demonstrated substantial inhibition of phosphorylation of CHK1, the downstream ATR substrate. CONCLUSION: To our knowledge, this report is the first of an ATR inhibitor as monotherapy and combined with carboplatin. M6620 was well tolerated, with target engagement and preliminary antitumor responses observed.


Subject(s)
Antineoplastic Agents/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Isoxazoles/administration & dosage , Neoplasms/drug therapy , Pyrazines/administration & dosage , Aged , Antineoplastic Agents/adverse effects , Antineoplastic Agents/pharmacokinetics , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Ataxia Telangiectasia Mutated Proteins/antagonists & inhibitors , Carboplatin/administration & dosage , Checkpoint Kinase 1/metabolism , Female , Humans , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Male , Maximum Tolerated Dose , Middle Aged , Neoplasms/genetics , Phosphorylation/drug effects , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects , Protein Kinase Inhibitors/pharmacokinetics , Pyrazines/adverse effects , Pyrazines/pharmacokinetics , Response Evaluation Criteria in Solid Tumors
16.
BMC Pharmacol Toxicol ; 21(1): 27, 2020 04 07.
Article in English | MEDLINE | ID: mdl-32264977

ABSTRACT

BACKGROUND: The present study aimed to develop and validate a rapid, selective, and reproducible ultra-performance liquid chromatography-tandem mass spectrometry separation method for the simultaneous determination of the levels of parecoxib and its main metabolite valdecoxib in rat plasma. Moreover, this method was applied to investigate the pharmacokinetics of parecoxib and valdecoxib in rats. METHODS: Following the addition of celecoxib as an internal standard, one-step protein precipitation by acetonitrile was used for sample preparation. The effective chromatographic separation was carried out using an ACQUITY UPLC®BEH C18 reversed phase column (2.1 mm × 50 mm, 1.7 µm particle size) with acetonitrile and water (containing 0.1% formic acid) as the mobile phase. The procedure was performed in less than 3 min with a gradient elution pumped at a flow rate of 0.4 ml/min. The electrospray ionization source was applied and operated in the positive ion mode and multiple reaction monitoring mode was used for quantification using the following: target fragment ions: m/z 371 → 234 for parecoxib, m/z 315 → 132 for valdecoxib and m/z 382 → 362 for celecoxib. RESULTS: The method validation demonstrated optimal linearity over the range of 50-10,000 ng/ml (r2 ≥ 0.9996) and 2.5-500 ng/ml (r2 ≥ 0.9991) for parecoxib and valdecoxib in rat plasma, respectively. CONCLUSIONS: The present study demonstrated a simple, sensitive and applicable method for the quantification of parecoxib and its main pharmacologically active metabolite valdecoxib following sublingual vein administration of 5 mg/kg parecoxib in rats.


Subject(s)
Cyclooxygenase 2 Inhibitors/blood , Isoxazoles/blood , Sulfonamides/blood , Animals , Chromatography, High Pressure Liquid/methods , Cyclooxygenase 2 Inhibitors/pharmacokinetics , Isoxazoles/pharmacokinetics , Male , Rats, Sprague-Dawley , Sulfonamides/pharmacokinetics , Tandem Mass Spectrometry
17.
Drug Des Devel Ther ; 14: 1117-1125, 2020.
Article in English | MEDLINE | ID: mdl-32214797

ABSTRACT

A method for the simultaneous determination of parecoxib and its metabolite valdecoxib in beagle plasma by UPLC-MS/MS was developed and validated. After the plasma was extracted by acetonitrile precipitation, the analytes were separated on an Acquity UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 µm) using acetonitrile-formic acid as the mobile phase in gradient mode. The analytes were monitored by multiple reaction monitoring (MRM) in electrospray negative ion mode. The mass transfer pairs were m/z 368.97→119.01 for parecoxib, m/z 312.89→118.02 for valdecoxib, and m/z 379.98→316.02 for celecoxib (internal standard, IS). The correlation coefficients of parecoxib and valdecoxib ranged from 5 to 4000 ng/mL were greater than 0.9998. The recovery of parecoxib and valdecoxib was greater than 82.54%. The inter- and intra-day precision RSD values were 1.36~3.65% and 2.28~5.91%, respectively. The accuracy of RE values were -1.38%~1.96%. Finally, the matrix effect (ME) and stability were also within acceptable criteria. This method had been successfully applied to the pharmacokinetics of parecoxib and valdecoxib in beagle plasma after injection of parecoxib (1.33 mg/kg, intramuscular injection).


Subject(s)
Isoxazoles/blood , Isoxazoles/metabolism , Sulfonamides/blood , Sulfonamides/metabolism , Animals , Chromatography, High Pressure Liquid , Dogs , Injections, Intramuscular , Isoxazoles/administration & dosage , Isoxazoles/pharmacokinetics , Molecular Structure , Sulfonamides/administration & dosage , Sulfonamides/pharmacokinetics , Tandem Mass Spectrometry
18.
Drug Dev Ind Pharm ; 46(4): 587-596, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32162981

ABSTRACT

Iloperidone (ILO) is an anti-psychotic, used in schizophrenia. It has low bioavailability (36%) due to low solubility and first pass effect. Oral solid self microemulsifying drug delivery system (SMEDDS) and liquisolid compact (LSC) of ILO were developed. The hypothesis is to test in vivo performance (PK and PD effects) of these delivery systems, as both systems improve dissolution. Based on solubility Capmul MCM, Labrafac WL 1349 were selected as oils, Lauroglycol 90 and PEG 600 were selected as surfactant and cosurfactant. Syloid XDP was optimized for adsorption of liquid SMEDDS. Syloid XDP and Aerosil 200 were optimized as carrier and coating material in the ratio of 15:1 w/w for liquisolid formulation. SEM and PXRD studies indicated no specific crystallinity due to bulkiness in both formulations, which showed similar flow and release behavior. Pharmacokinetic studies were performed for ILO Coarse suspension (CS), Tablet suspension (TS), optimized solid SMEDDS (A1X) and liquisolid compact (S3) in wistar rats. About 3.80 and 2.19-fold improvements in relative bioavailabilty were found for A1X and S3, respectively, when compared to CS. In comparison to TS, 2.61 and 1.51 fold improvements in bioavailability were found for A1X and S3, respectively. Further, Pharmacodynamic activity was studied by reversal of MK-801 induced hyperlocomotion in rats. A1X and S3 formulations showed maximum reversal after 15 min when compared to CS and found to have similar performance. Thus, in comparison to S3, A1X showed significant difference in pharmacokinetic effects but similar pharmacodynamic effects.


Subject(s)
Antipsychotic Agents/administration & dosage , Drug Carriers/chemistry , Isoxazoles/administration & dosage , Locomotion/drug effects , Piperidines/administration & dosage , Administration, Oral , Animals , Antipsychotic Agents/pharmacokinetics , Biological Availability , Chemistry, Pharmaceutical , Dizocilpine Maleate/administration & dosage , Emulsions , Excipients/chemistry , Humans , Isoxazoles/pharmacokinetics , Male , Models, Animal , Particle Size , Piperidines/pharmacokinetics , Rats , Schizophrenia/drug therapy , Solubility , Surface-Active Agents/chemistry , Suspensions , Tablets
19.
J Zoo Wildl Med ; 51(3): 691-695, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33480547

ABSTRACT

Sarcoptic mange continues to impact free-ranging mammal populations, including the American black bear (Ursus americanus). Administration of a single oral dose of fluralaner may be a viable treatment option for captive and free-ranging black bears affected by mange. This novel ectoparasitic in the isoxazoline class acts as an inhibitor of γ-aminobutyric acid (GABA)-gated chloride channels and l-glutamate-gated chloride channels (GluCls) and is commercially available in the United States as a flea and tick preventative medication for domestic dogs and cats. Pharmacokinetic parameters of fluralaner were evaluated in clinically healthy American black bear cubs (n = 10) administered a single oral dose of fluralaner at a targeted minimum dose of 25 mg/kg. Blood was collected at 24 hr and 7, 14, 21, 28, 35, 42, 49, 56, 63, and 70 days, and harvested plasma was analyzed for drug concentration using high-performance liquid chromatography. The average half-life (Ke t1/2) was determined to be 4.9 days, which is shorter than that published in domestic dogs. It was estimated that the average drug withdrawal time is approximately 64-72 days in this species.


Subject(s)
Acaricides/pharmacokinetics , Isoxazoles/pharmacokinetics , Ursidae/blood , Administration, Oral , Animals , Half-Life , Plasma/chemistry
20.
Clin Pharmacol Drug Dev ; 9(3): 395-410, 2020 04.
Article in English | MEDLINE | ID: mdl-31823525

ABSTRACT

Tropifexor (LJN452) is a potent, orally available, non-bile acid farnesoid X receptor agonist under clinical development for chronic liver diseases. Here, we present results from a first-in-human study of tropifexor following single- and multiple-ascending doses (SAD/MAD) and food effect substudy in healthy volunteers. The SAD study included 6 fasted cohorts receiving 10- to 3000-µg tropifexor or placebo and 1 cohort receiving 300-µg tropifexor with a high-fat meal. The MAD study included 4 lean cohorts receiving 10 to 100 µg and 1 obese cohort receiving 30-µg once-daily doses or placebo for 14 days. Pharmacodynamic assessment of fibroblast growth factor 19 and fasting plasma lipids was performed after dosing. Overall, 95 volunteers received at least 1 tropifexor or placebo dose. Tropifexor was well tolerated up to 3000 µg and 100 µg in the SAD and MAD studies, respectively; however, 2 subjects discontinued the MAD study due to asymptomatic elevation of liver transaminases. At single doses, tropifexor showed a moderate rate of absorption (median time to maximum concentration, 4 hours), dose-proportional increases in exposure, and elimination half-life of 13.5 to 21.9 hours. When taken with food, tropifexor exposure increased by ∼60%. With multiple dosing, steady state was reached on day 4 with <2-fold accumulation. Single and multiple doses showed dose-dependent increases in fibroblast growth factor 19. No changes in serum lipids were observed in tropifexor- vs placebo-treated obese subjects. In conclusion, tropifexor was well tolerated, had a pharmacokinetic profile suitable for once-daily dosing and showed dose-dependent target engagement without altering plasma lipids in healthy volunteers.


Subject(s)
Benzothiazoles/administration & dosage , Food-Drug Interactions , Isoxazoles/administration & dosage , Receptors, Cytoplasmic and Nuclear/agonists , Administration, Oral , Adult , Benzothiazoles/adverse effects , Benzothiazoles/pharmacokinetics , Diet, High-Fat , Dose-Response Relationship, Drug , Double-Blind Method , Fasting , Female , Half-Life , Humans , Isoxazoles/adverse effects , Isoxazoles/pharmacokinetics , Lipids/blood , Male , Middle Aged , Young Adult
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