Enhanced Sunscreen Effects via Layer-By-Layer Self-Assembly of Chitosan/Sodium Alginate/Calcium Chloride/EHA.

The sunscreen nanocapsules were successfully synthesized by the way of layer-by-layer self-assembly using charged droplets (prepared by emulsification of LAD-30, Tween-80 and EHA (2-Ethylhexyl-4-dimethylaminobenzoate)) as templates. Chitosan/sodium alginate/calcium chloride were selected as wall materials to wrap EHA. The emulsions with the ratio of Tween-80 to EHA (1:1) were stable. A stable NEI negative emulsion can be obtained when the ratio of Tween-80 and LAD-30 was 9:1. Chitosan solutions (50 kDa, 0.25 mg/mL) and sodium alginate solutions (0.5 mg/mL) were selected to prepare nanocapsules. The nanocapsules were characterized via some physico-chemical methods. Based on the synergistic effects of the electrostatic interaction between wall materials and emulsifiers, EHA was effectively encapsulated. DLS and TEM showed that the sunscreen nanocapsules were dispersed in a spherical shape with nano-size, with the increasing number of assembly layers, the size increased from 155 nm (NEI) to 189 nm (NEII) to 201 nm (NEIII) and 205 nm after solidification. The release studies in vitro showed sustained release behavior of the nanocapsules were observed with the increase of the number of deposition layers, implying a good coating effect. The sunscreen nanocapsules could control less than 50% the release of EHA after crosslinking of calcium chloride and sodium alginate, which also could effectively avoid the stimulation of the sun protection agent on the skin.

Development, Validation, and Application of the LC-MS/MS Method for Determination of 4-Acetamidobenzoic Acid in Pharmacokinetic Pilot Studies in Pigs.

Each drug has pharmacokinetics that must be defined for the substance to be used in humans and animals. Currently, one of the basic analytical tools for pharmacokinetics studies is high-performance liquid chromatography coupled with mass spectrometry. For this analytical method to be fully reliable, it must be properly validated. Therefore, the aims of this study were to develop and validate a novel analytical method for 4-acetamidobenzoic acid, a component of the antiviral and immunostimulatory drug Inosine Pranobex, and to apply the method in the first pharmacokinetics study of 4-acetamidobenzoic acid in pigs after oral administration. Inosine Pranobex was administered under farm conditions to pigs via drinking water 2 h after morning feeding at doses of 20, 40, and 80 mg/kg. For sample preparation, we used liquid-liquid extraction with only one step-protein precipitation with 1 mL of acetonitrile. As an internal standard, we used deuterium labeled 4-acetamidobenzoic acid. The results indicate that the described method is replicable, linear (r2 ≥ 0.99), precise (2.11% to 13.81%), accurate (89% to 98.57%), selective, and sensitive (limit of quantitation = 10 ng/mL). As sample preparation requires only one step, the method is simple, effective, cheap, and rapid. The results of the pilot pharmacokinetics study indicate that the compound is quickly eliminated (elimination half-life from 0.85 to 1.42 h) and rapidly absorbed (absorption half-life from 0.36 to 2.57 h), and that its absorption increases exponentially as the dose is increased.

Phase I study of daily and weekly regimens of the orally administered MDM2 antagonist idasanutlin in patients with advanced tumors.

Aim The oral MDM2 antagonist idasanutlin inhibits the p53-MDM2 interaction, enabling p53 activation, tumor growth inhibition, and increased survival in xenograft models. Methods We conducted a Phase I study of idasanutlin (microprecipitate bulk powder formulation) to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, pharmacodynamics, food effect, and clinical activity in patients with advanced malignancies. Schedules investigated were once weekly for 3 weeks (QW × 3), once daily for 3 days (QD × 3), or QD × 5 every 28 days. We also analyzed p53 activation and the anti-proliferative effects of idasanutlin. Results The dose-escalation phase included 85 patients (QW × 3, n = 36; QD × 3, n = 15; QD × 5, n = 34). Daily MTD was 3200 mg (QW × 3), 1000 mg (QD × 3), and 500 mg (QD × 5). Most common adverse events were diarrhea, nausea/vomiting, decreased appetite, and thrombocytopenia. Dose-limiting toxicities were nausea/vomiting and myelosuppression; myelosuppression was more frequent with QD dosing and associated with pharmacokinetic exposure. Idasanutlin exposure was approximately dose proportional at low doses, but less than dose proportional at > 600 mg. Although inter-patient variability in exposure was high with all regimens, cumulative idasanutlin exposure over the whole 28-day cycle was greatest with a QD × 5 regimen. No major food effect on pharmacokinetic exposure occurred. MIC-1 levels were higher with QD dosing, increasing in an exposure-dependent manner. Best response was stable disease in 30.6% of patients, prolonged (> 600 days) in 2 patients with sarcoma. Conclusions Idasanutlin demonstrated dose- and schedule-dependent p53 activation with durable disease stabilization in some patients. Based on these findings, the QD × 5 schedule was selected for further development. TRIAL REGISTRATION: NCT01462175 (ClinicalTrials.gov), October 31, 2011.

Specifically Eliminating Tumor-Associated Macrophages with an Extra- and Intracellular Stepwise-Responsive Nanocarrier for Inhibiting Metastasis.

Metastasis is the primary cause of death for most cancer patients, in which tumor-associated macrophages (TAMs) are involved through several mechanisms. While hitherto there is still a lack of study on exclusive elimination of TAMs to inhibit metastasis due to the difficulties in specific targeting of TAMs, we construct an extra- and intracellular stepwise-responsive delivery system p-(aminomethyl)benzoic acid (PAMB)/doxorubicin (DOX) to achieve specific TAM depletion for the first time, thereby preventing tumor metastasis. Once accumulated into the tumor, PAMB/DOX would stepwise responsively (hypoxia and reactive oxygen species (ROS) responsively) disintegrate to expose the TAM-targeting ligand and release DOX sequentially, which depletes TAMs effectively in vivo. Owing to the inhibition of extracellular matrix (ECM) degradation, neovascularization, and tumor invasion contributed by TAM depletion, lung metastasis was successfully inhibited. Furthermore, PAMB/DOX showed efficient inhibition against tumor growth as well as spontaneous metastasis formation when combined with additional chemotherapy, representing a safe and efficient nanoplatform to modulate the adverse tumor microenvironment via TAM elimination.

Phase 1 study of the MDM2 antagonist RO6839921 in patients with acute myeloid leukemia.

In acute myeloid leukemia (AML), TP53 mutations and dysregulation of wild-type p53 is common and supports an MDM2 antagonist as a therapy. RO6839921 is an inactive pegylated prodrug of the oral MDM2 antagonist idasanutlin (active principle [AP]) that allows for IV administration. This phase 1 monotherapy study evaluated the safety, pharmacokinetics, and pharmacodynamics of RO6839921 in patients with AML. Primary objectives identified dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD). Secondary objectives assessed pharmacokinetic, pharmacodynamic, and antileukemic activity. A total of 26 patients received 120-300 mg AP of idasanutlin. The MTD was 200 mg, with DLTs at 250 (2/8 patients) and 300 mg (2/5). Treatment-related adverse events in >20% of patients were diarrhea, nausea, vomiting, decreased appetite, and fatigue. Six deaths (23.1%) occurred, all unrelated to treatment. Pharmacokinetics showed rapid and near-complete conversion of the prodrug to AP and dose-proportional exposure across doses. Variability ranged from 30%-47% (22%-54% for idasanutlin). TP53 was 21 (87.5%) wild-type and 3 mutant (12.5%). The composite response rate (complete remission [CR], CR with incomplete hematologic recovery/morphological leukemia-free state [CRi/MLFS], or CR without platelet recovery [CRp]) was 7.7%. Antileukemic activity (CR, CRi/MLFS, partial response, hematologic improvement/stable disease) was observed in 11 patients (disease control rate, 42%): 10/11 were TP53 wild-type; 1 had no sample. p53 activation was demonstrated by MIC-1 induction and was associated with AP exposure. There was not sufficient differentiation or improvement in the biologic or safety profile compared with oral idasanutlin to support continued development of RO6839921. NCT02098967.

Metabolic activation of TM5441 in vitro and in vivo: Formation of reactive metabolites and human enzymes involved.

TM5441, a furan-containing drug, is an inhibitor of plasminogen activator inhibitor-1 (PAI-1), which can induce intrinsic apoptosis of human cancer cell lines. The aim of this study was to identify the reactive metabolites of TM5441 and to reveal the bioactivation pathways that are associated with its hepatotoxicity. The reactive metabolites were trapped by using glutathione (GSH) or N-acetyl-lysine (NAL) in rat, dog, and human liver microsomal incubation system after exposure to TM5441. Two metabolic activation pathways were disclosed. The first bioactivation pathway was dominated by Cytochrome P450 enzymes (CYP450s); TM5441 was metabolized into cis-2-butene-1,4-dial derivative dependent on NADPH, which can be trapped in the liver microsomal incubations fortified with GSH or NAL as trapping agents. Five metabolites (M1, M2, M9, M12 and M13) associated with GSH and three metabolites (M4, M7 and M14) associated with NAL were identified by liquid chromatography-high resolution mass spectrometry. The second bioactivation pathway was catalyzed by UDP-glucuronosyltransferases (UGTs); TM5441 was conjugated with glucuronide to form acyl-glucuronide (M10), which further reacted with GSH, resulting in the identification of a TM5441-S-acyl-GSH adduct (M11) in liver microsomal incubations fortified with uridine-5'-diphosphoglucuronidc acid (UDPGA) and GSH. M9, M10, M11, M12 and M13 were also detected in bile samples of rats given TM5441. Compared with rat, dog would display closer bioactivation profiles to human. The CYP450 enzyme responsible for the bioactivation of TM5441 was mainly identified as CYP3A4, using human recombinant CYP450 enzymes and specific inhibitory studies. The UGT enzymes responsible for the bioactivation of TM5441 mainly involved UGT2B7, 1A1 and 1A4. These results facilitate the understanding of the bioactivation of TM5441 and potential toxicological implications.

A single-center, open-label study investigating the excretion balance, pharmacokinetics, metabolism, and absolute bioavailability of a single oral dose of [14C]-labeled idasanutlin and an intravenous tracer dose of [13C]-labeled idasanutlin in a single cohort of patients with solid tumors.

PURPOSE: Idasanutlin, a selective small-molecule MDM2 antagonist in phase 3 testing for refractory/relapsed AML, is a non-genotoxic p53 activator with oral administration. To determine the need to conduct dedicated trial(s) for organ impairment on pharmacokinetic (PK) exposure and/or drug-drug interactions, a single dose of [14C]- and [13C]-labeled idasanutlin was evaluated. METHODS: This study was an open-label, non-randomized, single-center trial of idasanutlin to investigate the excretion balance, pharmacokinetics, metabolism, and absolute bioavailability of a single oral dose of [14C]-labeled idasanutlin and an IV tracer dose of [13C]-labeled idasanutlin in a single cohort of patients with solid tumors. After completing cycle 1 assessments, patients could have participated in an optional treatment extension of idasanutlin. Clinical endpoints were PK, and safety/tolerability. RESULTS: Co-administration of an oral dose of idasanutlin with an IV tracer dose revealed low systemic CL, a moderate Vd, and a moderate (40.1%) absolute bioavailability of idasanutlin. Idasanutlin and its major inactive metabolite, M4, were the major circulating moieties in plasma, and excretion of idasanutlin-associated radioactivity was primarily via the fecal route (91.5% of the dose), with negligible amounts recovered in urine, following oral administration. CONCLUSION: The clinical implications of this study support the conclusion that renal impairment is unlikely to significantly impact exposure to idasanutlin and M4 metabolite, whereas a significant hepatic impairment may potentially alter exposure to the parent drug and/or metabolite(s). The potential for drug-drug interactions is low.

Preclinical evaluation of the first intravenous small molecule MDM2 antagonist alone and in combination with temozolomide in neuroblastoma.

High-risk neuroblastoma, a predominantly TP53 wild-type (wt) tumour, is incurable in >50% patients supporting the use of MDM2 antagonists as novel therapeutics. Idasanutlin (RG7388) shows in vitro synergy with chemotherapies used to treat neuroblastoma. This is the first study to evaluate the in vivo efficacy of the intravenous idasanutlin prodrug, RO6839921 (RG7775), both alone and in combination with temozolomide in TP53 wt orthotopic neuroblastoma models. Detection of active idasanutlin using liquid chromatography-mass spectrometry and p53 pathway activation by ELISA assays and Western analysis showed peak plasma levels 1 h post-treatment with maximal p53 pathway activation 3-6 h post-treatment. RO6839921 and temozolomide, alone or in combination in mice implanted with TP53 wt SHSY5Y-Luc and NB1691-Luc cells showed that combined RO6839921 and temozolomide led to greater tumour growth inhibition and increase in survival compared to vehicle control. Overall, RO6839921 had a favourable pharmacokinetic profile consistent with intermittent dosing and was well tolerated alone and in combination. These preclinical studies support the further development of idasanutlin in combination with temozolomide in neuroblastoma in early phase clinical trials.

Lack of UGT polymorphism association with idasanutlin pharmacokinetics in solid tumor patients.

PURPOSE: Idasanutlin is a selective small-molecule MDM2 antagonist. It activates the tumor suppressor TP53 and is in phase 3 clinical trial for acute myeloid leukemia. Nonclinical studies have shown that glucuronidation is the major metabolizing mechanism for idasanutlin and UGT1A3 is the major metabolizing enzyme. There are reported examples of UGT polymorphisms associated with drug metabolism or response. Thus, the aim of this analysis is to investigate if UGT polymorphism is associated with idasanutlin pharmacokinetics. METHOD: Idasanutlin clearance was derived and normalized from two phase I studies. Its clearance level was compared between patients with different genotypes at 44 non-monomorphic UGT SNPs. Several single-locus and multi-locus association analysis, including haplotype association analysis and pairwise SNP interaction (epistasis) analyses were performed to investigate if there is any association between UGT genotypes and idasanutlin clearance. RESULTS AND CONCLUSION: A total of 69 patients who have both idasanutlin pharmacokinetic data and UGT genotyping data were analyzed for association. The major clearance enzyme for idasanutlin, UGT1A3, has no association with idasanutlin clearance. Further single-locus and multi-locus association analyses also suggest that no significant UGT polymorphism association with idasanutlin clearance can be detected with the current datasets. However, the possibility of association with rare allele(s) of UGT family genes cannot be excluded due to the limited sample size of the current phase I studies.

Novel therapeutic approaches in polycythemia vera.

Polycythemia vera (PV) is the most common Philadelphia chromosome-negative myeloproliferative neoplasm. Whereas low-risk patients are treated with aspirin and phlebotomy, high-risk patients receive cytoreductive therapy, which most commonly consists of hydroxyurea in the United States. Concerns about the long-term safety of hydroxyurea, as well as a desire for more efficacious and targeted therapy, have led to the development of novel therapies for high-risk patients with PV. Pegylated interferon (IFN) has shown promise in phase 2 studies of PV, and preliminary data from ongoing phase 3 studies suggest noninferiority as a frontline therapy. Efficient count control, tolerability, and even molecular responses as a salvage therapy have been demonstrated. Ropeginterferon-α-2b, a monopegylated IFN with a longer half-life and less frequent dose interval compared with recombinant or pegylated IFN, is an impressive agent in development. Ruxolitinib has a proven role as second-line therapy for PV, but an ongoing trial combining ruxolitinib and IFN as salvage therapy is under way. Early-phase clinical trials have also suggested that MDM2 inhibitors such as idasanutlin and histone deacetylase inhibitors should continue in their development. If these novel agents are able to modify the natural history of PV, the treatment paradigm in newly diagnosed patients will evolve from risk-adapted or reactive treatment toward early interventions.

Safety, tolerability, and pharmacokinetics of single and repeat ascending doses of CHF6001, a novel inhaled phosphodiesterase-4 inhibitor: two randomized trials in healthy volunteers.

PURPOSE: The purpose of this study was to evaluate safety, tolerability, and pharmacokinetics (PK) of CHF6001, an inhaled phosphodiesterase-4 inhibitor. MATERIALS AND METHODS: Two healthy volunteer, randomized, double-blind, placebo-controlled studies were conducted. In each, Part 1 evaluated single ascending doses, with PK sampling up to 48 hours post-dose; Part 2 evaluated multiple ascending doses (Study 1, 7 days; Study 2, 14 days), with PK sampling up to 24 hours post-dose on first and last day of each period. In Study 1, treatments were administered via single-dose dry-powder inhaler (SDDPI; Aerolizer): Part 1, 20, 100, 200, 400, 800, 1,600, and 2,000 µg or placebo; Part 2, 100, 300, 600, 1,200, and 1,600 µg or placebo once daily (OD). In Study 2, treatments were administered via multi-dose dry-powder inhaler (MDDPI; NEXThaler): Part 1, 2,400, 4,000, and 4,800 µg or placebo; Part 2, 1,200, 2,000, or 2,400 µg twice daily (BID) or placebo. Modeling and simulation then compared OD and BID dosing via MDDPI. RESULTS: There was a clear correlation between CHF6001 dose and plasma concentration, following single and multiple doses and using SDDPI and MDDPI. CHF6001 plasma concentration area under the curve (AUC) was dose proportional, with steady state slopes of the fitted line of 0.95 (90% CI: 0.86, 1.04) for AUC0-24 h in Study 1, and 0.85 (90% CI: 0.38, 1.32) for AUC0-12 h in Study 2. Bioavailability was30% higher with MDDPI than SDDPI. The PK simulation confirmed dose proportionality; the same total daily dose OD or BID via MDDPI resulted in similar 24 hours exposure, with BID dosing providing smaller fluctuation and lower maximum concentration. CHF6001 was well tolerated with no relationship between dose and adverse events. CONCLUSION: CHF6001 demonstrated a good safety profile. There was a clear dose proportionality for systemic exposure, with higher bioavailability via MDDPI, suggesting that the MDDPI provides better pulmonary drug deposition. BID dosing was associated with a better exposure profile.

First-in-human study to assess the safety, pharmacokinetics and pharmacodynamics of BMS-962212, a direct, reversible, small molecule factor XIa inhibitor in non-Japanese and Japanese healthy subjects.

AIMS: The aims of the present study were to assess the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of BMS-962212, a first-in-class factor XIa inhibitor, in Japanese and non-Japanese healthy subjects. METHODS: This was a randomized, placebo-controlled, double-blind, sequential, ascending-dose study of 2-h (part A) and 5-day (part B) intravenous (IV) infusions of BMS-962212. Part A used four doses (1.5, 4, 10 and 25 mg h-1 ) of BMS-962212 or placebo in a 6:2 ratio per dose. Part B used four doses (1, 3, 9 and 20 mg h-1 ) enrolling Japanese (n = 4 active, n = 1 placebo) and non-Japanese (n = 4 active, n = 1 placebo) subjects per dose. The PK, PD, safety and tolerability were assessed throughout the study. RESULTS: BMS-962212 was well tolerated; there were no signs of bleeding, and adverse events were mild. In parts A and B, BMS-962212 demonstrated dose proportionality. The mean half-life in parts A and B ranged from 2.04 to 4.94 h and 6.22 to 8.65 h, respectively. Exposure-dependent changes were observed in the PD parameters, activated partial thromboplastin time (aPTT) and factor XI clotting activity (FXI:C). The maximum mean aPTT and FXI:C change from baseline at 20 mg h-1 in part B was 92% and 90%, respectively. No difference was observed in weight-corrected steady-state concentrations, aPTT or FXI:C between Japanese and non-Japanese subjects (P > 0.05). CONCLUSION: BMS-962212 has tolerability, PK and PD properties suitable for investigational use as an acute antithrombotic agent in Japanese or non-Japanese subjects.

Effects of posaconazole (a strong CYP3A4 inhibitor), two new tablet formulations, and food on the pharmacokinetics of idasanutlin, an MDM2 antagonist, in patients with advanced solid tumors.

PURPOSE: Idasanutlin, a selective small-molecule MDM2 antagonist in phase 3 testing for refractory/relapsed AML, is a non-genotoxic oral p53 activator. To optimize its dosing conditions, a number of clinical pharmacology characteristics were examined in this multi-center trial in patients with advanced solid tumors. METHOD: This was an open-label, single-dose, crossover clinical pharmacology study investigating the effects of strong CYP3A4 inhibition with posaconazole (Part 1), two new oral formulations (Part 2), as well as high-energy/high-fat and low-energy/low-fat meals (Part 3) on the relative bioavailability of idasanutlin. After completing Part 1, 2, or 3, patients could have participated in an optional treatment with idasanutlin. Clinical endpoints were pharmacokinetics (PK), pharmacodynamics (PD) of MIC-1 elevation (Part 1 only), and safety/tolerability. RESULTS: The administration of posaconazole 400 mg BID × 7 days with idasanutlin 800 mg resulted in a slight decrease (7%) in Cmax and a modest increase (31%) in AUC for idasanutlin, a marked reduction in Cmax (~ 60%) and AUC0 (~ 50%) for M4 metabolite, and a minimal increase (~ 24%) in serum MIC-1 levels. Cmax and AUC were both 45% higher for the SDP formulation. While the low-fat meal caused a less than 20% increase in all PK exposure parameters with the 90% CI values just outside the upper end of the equivalence criteria (80-125%), the high-fat meal reached bioequivalence with dosing under fasting. CONCLUSION: In patients with solid tumors, multiple doses of posaconazole, a strong CYP3A4 inhibitor, minimally affected idasanutlin PK and PD without clinical significance. The SDP formulation improved rBA/exposures by ~ 50% without major food effect.

Investigation of Lung Pharmacokinetic of the Novel PDE4 Inhibitor CHF6001 in Preclinical Models: Evaluation of the PreciseInhale Technology.

BACKGROUND: Preclinical evaluation of new chemical entities (NCEs) designed to be administered by inhalation route requires lung administration to rodents, especially in the discovery phase. Different administration methods have been used until now, but more efforts are required to obtain controlled and reproducible lung deposition when only small amounts of neat powder material are available. METHODS: The PreciseInhale platform used in the present study enables well-controlled powder aerosol exposures with only small amounts of micronized neat material, providing data on inhalation pharmacokinetic (PK) of NCEs at a very early stage. The DustGun aerosol technology uses compressed air to generate a respirable aerosol from milligram-amounts of powder that is delivered to one animal at a time. The new methodology was used to investigate the inhalation PK and lung retention in the rat of the novel Chiesi PDE4 inhibitor CHF6001 in three exposure models of the PreciseInhale platform: nose-only, intratracheally intubated rat, and the isolated, ventilated, and perfused rat lung. Results were compared with data from two other pulmonary delivery systems commonly used in preclinical studies: liquid instillation and powder insufflation. RESULTS: Administration of micronized CHF6001 using the PreciseInhale system yielded lung exposures in the same range as the other tested devices, but the reproducibility in lung deposition was improved. The initial amount of CHF6001 in lungs at the first sampling time point was close to the predetermined target dose. Tracheal deposition with PreciseInhale (0.36 ± 0.22 µg) was significantly less than with other tested delivery systems: PennCentury (23.7 ± 3.2 µg) and Airjet (25.6 ± 7.2 µg). CONCLUSIONS: The PreciseInhale platform enabled the administration of CHF6001 powder with good accuracy and reproducibility, with low tracheal deposition. The new platform can be used at an early discovery stage to obtain inhalatory PK data for respirable aerosols of neat NCE powder without excipients and with minimal use of dry powder formulation work.

Discovery of a Parenteral Small Molecule Coagulation Factor XIa Inhibitor Clinical Candidate (BMS-962212).

Factor XIa (FXIa) is a blood coagulation enzyme that is involved in the amplification of thrombin generation. Mounting evidence suggests that direct inhibition of FXIa can block pathologic thrombus formation while preserving normal hemostasis. Preclinical studies using a variety of approaches to reduce FXIa activity, including direct inhibitors of FXIa, have demonstrated good antithrombotic efficacy without increasing bleeding. On the basis of this potential, we targeted our efforts at identifying potent inhibitors of FXIa with a focus on discovering an acute antithrombotic agent for use in a hospital setting. Herein we describe the discovery of a potent FXIa clinical candidate, 55 (FXIa Ki = 0.7 nM), with excellent preclinical efficacy in thrombosis models and aqueous solubility suitable for intravenous administration. BMS-962212 is a reversible, direct, and highly selective small molecule inhibitor of FXIa.

Bioconcentration and multi-biomarkers of organic UV filters (BM-DBM and OD-PABA) in crucian carp.

Organic UV filters (OUV-Fs) are increasingly used in sunscreens and personal care products. In the present work, the bioconcentration and multi-biomarker effects of butyl methoxydibenzoylmethane (BM-DBM) and ethylhexyl dimethyl p-aminobenzoate (OD-PABA) were investigated in crucian carp (Carassius auratus). The fish were exposed to various concentrations of BM-DBM (3.88, 35.61, 181.85 and 337.15µg/L), OD-PABA (4.66, 53.83, 264.22 and 459.32µg/L) and their mixture (2.31+2.79, 23.69+26.18, 97.37+134.81 and 193.93+246.08µg/L) for 28 days. The maximal concentrations of two OUV-Fs were detected in the fish liver, followed by the brain, kidney, gill and muscle in most cases. The maximal BCF values of OD-PABA calculated in various exposure concentrations were 0.37 - 101.21 in single exposure groups and 0.11 - 31.09 in mixed exposure groups. Acetylcholinesterase (AChE) activity was significantly inhibited by BM-DBM as well as the mixtures at all of the exposure concentrations and by OD-PABA at higher concentrations (≥264.22µg/L) during 28 days of exposure. The maximal inhibition rates of AChE activity reached 64.04% for BM-DBM, 41.05% for OD-PABA and 61.50% for the mixtures at the highest concentration, which indicated that these two OUV-Fs might damage the central nervous system. Concerning oxidative stress status, BM-DBM and the mixtures significantly increased superoxide dismutase (SOD) and glutathione reductase (GR) activities and inhibited catalase (CAT) activity, while OD-PABA caused a significant increase of GR and CAT activities. AChE and GR activities seemed to be more sensitive biomarkers for BM-DBM and OD-PABA.

Evaluation of the Effects of CHF6001, an Inhaled PDE4 Inhibitor, on Cardiac Repolarization and Cardiac Arrhythmias in Healthy Volunteers.

Chronic obstructive pulmonary disease (COPD) is a multicomponent condition characterized by airway inflammation and associated to comorbidities, including cardiovascular diseases. Among anti-inflammatory agents in development for COPD, the phosphodiesterase inhibitors administrated by inhalation have the potential for increased efficacy and reduced systemic side effects. CHF6001 is an inhaled PDE4 inhibitor with proven anti-inflammatory properties in animal models. This randomized, double-blind, placebo-controlled study was aimed to demonstrate its cardiovascular safety and tolerability in healthy male volunteers with normal electrocardiogram and cardiac parameters. Single and multiple ascending doses (7 days of administration) of CHF6001 were administered. Three electrocardiograms were recorded at several pharmacokinetic time points and at each time points, postdose heart rate, QRS and PR intervals, and presence of arrhythmia were evaluated. In single ascending dose, QTcF intervals did not increase more than 30 milliseconds from the baseline, all heart rate was between 45 and 100 bpm, and no statistically significant differences were observed in PR and QRS intervals. In multiple ascending dose, cardiac parameters did not differ significantly from baseline. In the pharmacokinetic/pharmacodynamic analysis, no medically or clinically significant changes were found. Further studies are ongoing to demonstrate that CHF6001 is safe and well tolerated in COPD patients as well.

Formation of active products of benzaldehyde dimethane sulfonate (NSC 281612, DMS612) in human blood and plasma and their activity against renal cell carcinoma lines.

Benzaldehyde dimethane sulfonate (BEN, DMS612, NSC281612) is an alkylating agent with activity against renal cell carcinoma and is being evaluated clinically. To support clinical trials, we developed an LC-MS/MS assay to detect and quantitate BEN and its metabolites/decomposition products. We tested the stability and products of BEN and benzoic acid dimethane sulfonate (BA) in plasma, blood and five renal carcinoma cell lines in vitro. Further, we determined the IC(50) of BEN, BA and four of their products in these cell lines. Low temperature and pH stabilized the analytes, and utilizing this resulted in an accurate, precise and reproducible assay. The half-lives of BEN and BA added to plasma in vitro were 220 and 5 min, while the half-life of BEN in whole blood was 18 min. The generation and degradation of up to 12 analytes were monitored, and structures confirmed with available authentic standards. The IC(50) for BEN was 5- to 500-fold lower than that of any of its products, while the cellular metabolic activity toward BEN correlated with ALDH activity and IC(50) values. We detected six of the in vitro products and their respective glucuronides in murine plasma after dosing BEN. The information gained from these experiments will be instrumental in the evaluation of the pharmacology of BEN in ongoing human trials.