A validated LC-MS/MS method for determination of neuro-pharmacokinetic behavior of niraparib in brain tumor patients

Niraparib is a potent and orally bioavailable inhibitor of poly (ADP-ribose) polymerase (PARP) with high specificity for isoforms 1 and 2. It has been approved by the U.S. Food and Drug Administration for ovarian cancer maintenance therapy and is currently under development for various cancers, including glioblastoma. To assess central nervous system (CNS) penetration of niraparib in glioblastoma patients, a novel bioanalytical method was developed to measure total and unbound niraparib levels in human brain tumor tissue and cerebrospinal fluid (CSF). The method was validated using plasma as a surrogate matrix over the concentration range of 1-10,000 nM on an LC-MS/MS system. The MS/MS detection was conducted in positive electrospray ionization mode, while chromatography was performed using a Kinetex™ PS C18 column with a total 3.5-minute gradient elution run time. The maximum coefficient of variation for both intra- and inter-day precision was 10.6%, with accuracy ranging from 92.8% - 118.5% across all matrices. Niraparib was stable in human brain homogenate for at least 6 hours at room temperature (RT) and 32 days at -20°C, as well as in stock and working solutions for at least 21 hours (RT) and 278 days (4°C). Equilibrium dialysis experiments revealed the fractions unbound of 0.05 and 0.16 for niraparib in human brain and plasma, respectively. The validated method is currently employed to assess niraparib levels in human glioblastoma tissue, CSF, and plasma in an ongoing trial on newly diagnosed glioblastoma and recurrent IDH1/2(+) ATRX mutant glioma patients (NCT05076513). Initial results of calculated total (Kp) and unbound (Kp,uu) tumor-to-plasma partition coefficients indicate significant brain penetration ability of niraparib in glioblastoma patients.

PET Quantification of [18F]VAT in Human Brain and Its Test-Retest Reproducibility and Age Dependence

Molecular imaging of brain vesicular acetylcholine transporter provides a biomarker to explore cholinergic systems in humans. We aimed to characterize the distribution of, and optimize methods to quantify, the vesicular acetylcholine transporter-specific tracer (-)-(1-(8-(2-[18F]fluoroethoxy)-3-hydroxy-1,2,3,4-tetrahydronaphthalen-2-yl)-piperidin-4-yl)(4-fluorophenyl)methanone ([18F]VAT) in the brain using PET. Methods: Fifty-two healthy participants aged 21-97 y had brain PET with [18F]VAT. [3H]VAT autoradiography identified brain areas devoid of specific binding in cortical white matter. PET image-based white matter reference region size, model start time, and duration were optimized for calculations of Logan nondisplaceable binding potential (BPND). Ten participants had 2 scans to determine test-retest variability. Finally, we analyzed age-dependent differences in participants. Results: [18F]VAT was widely distributed in the brain, with high striatal, thalamic, amygdala, hippocampal, cerebellar vermis, and regionally specific uptake in the cerebral cortex. [3H]VAT autoradiography-specific binding and PET [18F]VAT uptake were low in white matter. [18F]VAT SUVs in the white matter reference region correlated with age, requiring stringent erosion parameters. Logan BPND estimates stabilized using at least 40 min of data starting 25 min after injection. Test-retest variability had excellent reproducibility and reliability in repeat BPND calculations for 10 participants (putamen, 6.8%; r > 0.93). We observed age-dependent decreases in the caudate and putamen (multiple comparisons corrected) and in numerous cortical regions. Finally, we provide power tables to indicate potential mean differences that can be detected between 2 groups of participants. Conclusion: These results validate a reference region for BPND calculations and demonstrate the viability, reproducibility, and utility of using the [18F]VAT tracer in humans to quantify cholinergic pathways.

CYP3A4 and CYP2C19 genetic polymorphisms and myricetin interaction on tofacitinib metabolism

Tofacitinib can effectively improve the clinical symptoms of rheumatoid arthritis (RA) patients. In this current study, a recombinant human CYP2C19 and CYP3A4 system was operated to study the effects of recombinant variants on tofacitinib metabolism. Moreover, the interaction between tofacitinib and myricetin was analyzed in vitro. The levels of M9 (the main metabolite of tofacitinib) was detected by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The findings revealed that 11 variants showed significant changes in the levels of M9 compared to CYP3A4.1, while the other variants didn't reveal any remarkable significances. Compared with CYP2C19.1, 11 variants showed increases in the levels of M9, and 10 variants showed decreases. Additionally, it was demonstrated in vitro that the inhibition of tofacitinib by myricetin was a non-competitive type in rat liver microsomes (RLM) and human liver microsomes (HLM). However, the inhibitory mechanism was a competitive type in CYP3A4.18, and mixed type in CYP3A4.1 and .28, respectively. The data demonstrated that gene polymorphisms and myricetin had significant effects on the metabolism of tofacitinib, contributing to important clinical data for the precise use.

Formulation and evaluation of dissolving microneedle for transdermal delivery of piperine: the effect of polymers concentration

This research aims to develop the formulation of Dissolving Microneedle Piperine (DMNs PIP) and evaluate the effect of polymer concentration on characterisation and permeation testing results in ex vivo. DMNs PIP were prepared from varying concentrations of piperine (PIP) (10, 15, and 20% w/w) and polymers of polyvinyl alcohol (PVA): Polyvinyl pyrrolidone (30:60 and 60:25), respectively. Then the morphological evaluation of the formula was carried out, followed by mechanical strength testing. Furthermore, the density, LOD, and weight percentage of piperine in the dried microneedle were calculated and the determination of volume, needle weight and piperine weight and analysed. Ex vivo testing, X-Ray Diffraction, FTIR and hemolysis tests were carried out. PIP with PVA and PVP (F1) polymers produced DMN with mechanical strength (8.35 ± 0.11%) and good penetration ability. In vitro tests showed that the F1 polymer mixture gave good penetration (95.02 ± 1.42 μg/cm2), significantly higher than the F2, F3, F4, and F5 polymer mixtures. The DMNs PIP characterisation results through XRD analysis showed a distinctive peak in the 20-30 region, indicating the presence of crystals. The FTIR study showed that the characteristics of piperine found in DMNs PIP indicated that piperine did not undergo interactions with polymers. The results of the ex vivo study through DMNs PIP hemolytic testing showed no hemolysis occurred, with the hemolysis index below the 5% threshold reported in the literature. These findings indicate that DMNs PIP is non-toxic and safe to use as alternative for treating inflammation.

A dose-ranging study of the physiological and self-reported effects of repeated, rapid infusion of remifentanil in people with opioid use disorder and physical dependence on fentanyl

RATIONALE

Understanding mechanisms of drug use decisions will inform the development of treatments for opioid use disorder (OUD). Decision-making experiments using neurobehavioral approaches require many trials or events of interest for statistical analysis, but the pharmacokinetics of most opioids limit dosing in humans.

OBJECTIVES

This experiment characterized the effects of repeated infusions of the ultra-short acting opioid remifentanil in people with OUD and physical opioid dependence.

METHODS

An inpatient study using a within-subjects, single-blind, escalating, within-session, pre-post design was conducted. Seven (3 female) subjects were maintained on oral oxycodone (40-60 mg, 4x/day = 160-240 total mg/day) for seven days prior to the dose-ranging session. Subjects received infusions of three ascending remifentanil doses (0.03, 0.1, 0.3 mcg/kg/infusion in 2 subjects; 0.1, 0.3, 1.0 mcg/kg/infusion in 5 subjects) every minute for 40 min per dose, with infusions administered over 5 s to model naturalistic delivery rates. End tidal carbon dioxide, respiration rate, oxygen saturation (SpO2) and heart rate were measured continuously. Blood pressure (BP), pupil diameter and self-reported drug effects were measured every 5 min.

RESULTS

Pupil diameter, SpO2 and systolic BP decreased, and ratings on prototypic subjective effects questionnaire items increased, as a function of remifentanil dose. The number of infusions held because of sedation or physiological parameters exceeding predetermined cutoffs also increased with dose.

CONCLUSIONS

This experiment established doses and procedures for the safe delivery of rapid, repeated remifentanil infusions to individuals with OUD and physical fentanyl dependence, which can be applied to the mechanistic study of opioid use decisions.

A Drug-Drug Interaction Study to Evaluate the Impact of Rimegepant on OCT2- and MATE1-Mediated Transport of Metformin in Healthy Participants

Rimegepant is a calcitonin gene-related peptide receptor antagonist approved for migraine treatment. This phase 1, open-label, single-center, fixed-sequence study evaluated the effect of rimegepant on the pharmacokinetics (PK) of metformin. Twenty-eight healthy participants received metformin 500 mg twice daily from Days 1 to 4 and Days 7 to 10, and once daily on Days 5 and 11. Rimegepant, 75 mg tablet, was administered once daily from Days 9 to 12. At pre-specified time points, plasma metformin concentration, serum glucose levels, and safety and tolerability were evaluated. A 16% increase in the area under the plasma metformin concentration-time curve (AUC) for 1 dosing interval (AUC0-τ,ss), a statistically insignificant increase in maximum and minimum steady-state metformin concentration (Cmax,ss and Cmin,ss), and a decrease in metformin renal clearance were observed on Day 11 following metformin-rimegepant coadministration compared with metformin alone; however, the changes were not clinically relevant. Additionally, coadministration of rimegepant with metformin did not induce clinically meaningful change in the maximum observed glucose concentration (Gmax) or AUCgluc compared with metformin alone. Overall, rimegepant and metformin coadministration did not result in clinically relevant changes in metformin PK, renal clearance, or the antihyperglycemic effects of metformin. Rimegepant is considered safe for use with metformin.

Tofacitinib pharmacokinetics in children and adolescents with juvenile idiopathic arthritis

These analyses characterized tofacitinib pharmacokinetics (PKs) in children and adolescents with juvenile idiopathic arthritis (JIA). Data were pooled from phase I (NCT01513902), phase III (NCT02592434), and open-label, long-term extension (NCT01500551) studies of tofacitinib tablet/solution (weight-based doses administered twice daily [b.i.d.]) in patients with JIA aged 2 to less than 18 years. Population PK modeling used a nonlinear mixed-effects approach, with covariates identified using stepwise forward-inclusion backward-deletion procedures. Simulations were performed to derive dosing recommendations for children and adolescents with JIA. Two hundred forty-six pediatric patients were included in the population PK model. A one-compartment model with first-order elimination and absorption with body weight as a covariate for oral clearance and apparent volume of distribution sufficiently described the data. Oral solution was associated with comparable average concentration (Cavg) and slightly higher (113.9%) maximum concentration (Cmax) versus tablet, which was confirmed by a subsequent randomized, open-label, bioavailability study conducted in healthy adult participants (n = 12) by demonstrating adjusted geometric mean ratios (90% confidence interval) between oral solution and tablet of 1.04 (1.00-1.09) and 1.10 (1.00-1.21) for area under the curve extrapolated to infinity and Cmax, respectively (NCT04111614). A dosing regimen of 3.2 mg b.i.d. solution in patients 10 to less than 20 kg, 4 mg b.i.d. solution in patients 20 to less than 40 kg, and 5 mg b.i.d. tablet/solution in patients greater than or equal to 40 kg, irrespective of age, was proposed to achieve constant Cavg across weight groups. In summary, population PK characterization informed a simplified tofacitinib dosing regimen that has been implemented in pediatric patients with JIA.

Demonstrating Bioequivalence for Two Dose Strengths of Niraparib and Abiraterone Acetate Dual-Action Tablets Versus Single Agents: Utility of Clinical Study Data Supplemented with Modeling and Simulation

BACKGROUND AND OBJECTIVE

The combination of niraparib and abiraterone acetate (AA) plus prednisone is under investigation for the treatment of patients with metastatic castration-resistant prostate cancer (mCRPC) and metastatic castration-sensitive prostate cancer (mCSPC). Regular-strength (RS) and lower-strength (LS) dual-action tablets (DATs), comprising niraparib 100 mg/AA 500 mg and niraparib 50 mg/AA 500 mg, respectively, were developed to reduce pill burden and improve patient experience. A bioequivalence (BE)/bioavailability (BA) study was conducted under modified fasting conditions in patients with mCRPC to support approval of the DATs.

METHODS

This open-label randomized BA/BE study (NCT04577833) was conducted at 14 sites in the USA and Europe. The study had a sequential design, including a 21-day screening phase, a pharmacokinetic (PK) assessment phase comprising three periods [namely (1) single-dose with up to 1-week run-in, (2) daily dose on days 1-11, and (3) daily dose on days 12-22], an extension where both niraparib and AA as single-agent combination (SAC; reference) or AA alone was continued from day 23 until discontinuation, and a 30-day follow-up phase. Patients were randomly assigned in a parallel-group design (four-sequence randomization) to receive a single oral dose of niraparib 100 mg/AA 1000 mg as a LS-DAT or SAC in period 1, and patients continued as randomized into a two-way crossover design during periods 2 and 3 where they received niraparib 200 mg/AA 1000 mg once daily as a RS-DAT or SAC. The design was powered on the basis of crossover assessment of RS-DAT versus SAC. During repeated dosing (periods 2 and 3, and extension phase), all patients also received prednisone/prednisolone 5 mg twice daily. Plasma samples were collected for measurement of niraparib and abiraterone plasma concentrations. Statistical assessment of the RS-DAT and LS-DAT versus SAC was performed on log-transformed pharmacokinetic parameters data from periods 2 and 3 (crossover) and from period 1 (parallel), respectively. Additional paired analyses and model-based bioequivalence assessments were conducted to evaluate the similarity between the LS-DAT and SAC.

RESULTS

For the RS-DAT versus SAC, the 90% confidence intervals (CI) of geometric mean ratios (GMR) for maximum concentration at a steady state (Cmax,ss) and area under the plasma concentration-time curve from 0-24 h at a steady state (AUC 0-24h,ss) were respectively 99.18-106.12% and 97.91-104.31% for niraparib and 87.59-106.69 and 86.91-100.23% for abiraterone. For the LS-DAT vs SAC, the 90% CI of GMR for AUC0-72h of niraparib was 80.31-101.12% in primary analysis, the 90% CI of GMR for Cmax,ss and AUC 0-24h,ss of abiraterone was 85.41-118.34% and 86.51-121.64% respectively, and 96.4% of simulated LS-DAT versus SAC BE trials met the BE criteria for both niraparib and abiraterone.

CONCLUSIONS

The RS-DAT met BE criteria (range 80%-125%) versus SAC based on 90% CI of GMR for Cmax,ss and AUC 0-24h,ss. The LS-DAT was considered BE to SAC on the basis of the niraparib component meeting the BE criteria in the primary analysis for AUC 0-72h; abiraterone meeting the BE criteria in additional paired analyses based on Cmax,ss and AUC 0-24h,ss; and the percentage of simulated LS-DAT versus SAC BE trials meeting the BE criteria for both.

CLINICALTRIALS

GOV IDENTIFIER

NCT04577833.

The use of microtracers in food-effect trials: An alternative study design for toxic drugs with long half-lives exemplified by the case for alectinib

The traditional design of food-effect studies has a high patient burden for toxic drugs with long half-lives (e.g., anticancer agents). Microtracers could be used to assess food-effect in patients without influencing their ongoing treatment. The feasibility of a microtracer food-effect study during steady-state of the therapeutic drug was investigated in an in silico simulation study with alectinib as an example for a relative toxic drug with a long half-life. Microtracer pharmacokinetics were simulated based on a previously published population pharmacokinetic model and used for estimation of a model with and a model without food as a covariate on oral bioavailability of alectinib (assuming a 40% food-effect). Power was defined as the fraction of clinical trials where a significant (p < 0.01) food-effect was identified. The proposed study design of 10 patients on steady-state treatment, 10 blood samples collected within 24 h after administration and an assumed food-effect of 40% had a power of 99.9%. The mean estimated food-effect was 39.8% (80% confidence interval: 31.0%-48.6%). The feasibility of microtracer food-effect studies was demonstrated. The design of the microtracer food-effect study allowed estimation of the food-effect with minimal influence on therapeutic treatment and reducing patient burden compared to the traditional study design for toxic drugs with long half-lives.

Population Pharmacokinetic and Exposure-Safety Analyses of Ibrutinib for the Treatment of Chronic Graft-Versus-Host Disease

The population pharmacokinetic (PK) and exposure-response (E-R) analyses for the safety of ibrutinib for the treatment of chronic graft-versus-host disease (cGVHD) is presented. This work aims to develop a population PK model for ibrutinib based on data from clinical studies in subjects with cGVHD, to evaluate the impact of intrinsic and extrinsic factors on PK parameters as well as systemic exposure levels, and to assess an E-R relationship for selected safety end points. Pooled data from 162 subjects with cGVHD enrolled in 4 clinical studies were included in the population PK analysis. In the studies, an ibrutinib dose of 420 mg once daily was administered orally. With the exception of 1 study, the study protocols instructed for a reduction of the ibrutinib dose to 140 or 280 mg once daily, depending on concomitant CYP3A inhibitor use. Concomitant CYP3A inhibitor use was found to be a primary covariate for relative bioavailability (F1): the F1 value increased 2.22-fold with concomitant moderate CYP3A inhibitors and 3.09-fold with concomitant strong CYP3A inhibitors, compared with the F1 value in the absence of CYP3A inhibitors. In addition, Japanese ethnicity led to an F1 value that was 1.70-fold higher than that in the non-Japanese population. Simulations using the final PK model suggest that ibrutinib exposure was appropriately controlled within the therapeutic range in the entire cGVHD population by applying dose reductions depending on the use of CYP3A inhibitors, and that additional dose modification for the Japanese population would not be required. The subsequent E-R analysis suggests no apparent association between the systemic exposure to ibrutinib and the selected safety end points.

High-resolution accurate mass approach to characterization of SCO-267 metabolites using liquid chromatography hybrid quadrupole Orbitrap mass spectrometry

RATIONALE

SCO-267 is a potent full agonist of G-protein-coupled receptor 40. As a promising therapeutic agent for type 2 diabetes mellitus, it is necessary to elucidate its metabolite profiles during the stage of drug development for safety considerations.

METHODS

The in vitro metabolism was investigated by incubating SCO-267 (5 μM) with liver microsomes and hepatocytes (rat and human). For in vivo metabolism, SCO-267 (10 mg/kg) was orally administered to rats and plasma samples were collected. The metabolites were identified via measurements of accurate mass, elemental composition and product ions using liquid chromatography coupled to hybrid quadrupole Orbitrap high-resolution mass spectrometry (LC-Orbitrap-MS).

RESULTS

A total of 19 metabolites were structurally identified. M2 (hydroxyl-SCO-267), M15 (SCO-267-acyl-glucuronide), M16 (desmethyl-SCO-267) and M17 (desneopentyl-SCO-267) were verified with reference standards. M2, M11, M16 and M17 were the major metabolites originating from hydroxylation, O-demethylation and N-dealkylation, respectively. Phenotyping study with recombinant human P450 enzymes demonstrated that hydroxylation (M2 and M11) was mainly catalyzed by CYP2C8 and 3A4; demethylation (M16) was mainly catalyzed by CYP2D6, and less catalyzed by CYP2C8 and 3A4; and N-dealkylation (M17) was exclusively triggered by CYP3A4.

CONCLUSIONS

Hydroxylation, O-demethylation, N-dealkylation and acyl glucuronidation were the major metabolic pathways of SCO-267. This study is the first to discover the metabolic fates of SCO-267, which provides a basis for safety assessment of this drug candidate.

Drug Distribution in Brain and Cerebrospinal Fluids in Relation to IC50 Values in Aging and Alzheimer's Disease, Using the Physiologically Based LeiCNS-PK3.0 Model

Background

Very little knowledge exists on the impact of Alzheimer’s disease on the CNS target site pharmacokinetics (PK).

Aim

To predict the CNS PK of cognitively healthy young and elderly and of Alzheimer’s patients using the physiologically based LeiCNS-PK3.0 model.

Methods

LeiCNS-PK3.0 was used to predict the PK profiles in brain extracellular (brain_ECF) and intracellular (brain_ICF) fluids and cerebrospinal fluid of the subarachnoid space (CSF_SAS) of donepezil, galantamine, memantine, rivastigmine, and semagacestat in young, elderly, and Alzheimer’s patients. The physiological parameters of LeiCNS-PK3.0 were adapted for aging and Alzheimer’s based on an extensive literature search. The CNS PK profiles at plateau for clinical dose regimens were related to in vitro IC₅₀ values of acetylcholinesterase, butyrylcholinesterase, N-methyl-D-aspartate, or gamma-secretase.

Results

The PK profiles of all drugs differed between the CNS compartments regarding plateau levels and fluctuation. Brain_ECF, brain_ICF and CSF_SAS PK profile relationships were different between the drugs. Aging and Alzheimer’s had little to no impact on CNS PK. Rivastigmine acetylcholinesterase IC₅₀ values were not reached. Semagacestat brain PK plateau levels were below the IC₅₀ of gamma-secretase for half of the interdose interval, unlike CSF_SAS PK profiles that were consistently above IC_50.

Conclusion

This study provides insights into the relations between CNS compartments PK profiles, including target sites. CSF_SAS PK appears to be an unreliable predictor of brain PK. Also, despite extensive changes in blood-brain barrier and brain properties in Alzheimer’s, this study shows that the impact of aging and Alzheimer’s pathology on CNS distribution of the five drugs is insignificant.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-022-03281-3.

In vitro investigations into the roles of CYP450 enzymes and drug transporters in the drug interactions of zanubrutinib, a covalent Bruton's tyrosine kinase inhibitor

Zanubrutinib is a highly selective, potent, orally available, targeted covalent inhibitor (TCI) of Bruton's tyrosine kinase (BTK). This work investigated the in vitro drug metabolism and transport of zanubrutinib, and its potential for clinical drug-drug interactions (DDIs). Phenotyping studies indicated cytochrome P450 (CYP) 3A are the major CYP isoform responsible for zanubrutinib metabolism, which was confirmed by a clinical DDI study with itraconazole and rifampin. Zanubrutinib showed mild reversible inhibition with half maximal inhibitory concentration (IC50 ) of 4.03, 5.69, and 7.80 μM for CYP2C8, CYP2C9, and CYP2C19, respectively. Data in human hepatocytes disclosed induction potential for CYP3A4, CYP2B6, and CYP2C enzymes. Transport assays demonstrated that zanubrutinib is not a substrate of human breast cancer resistance protein (BCRP), organic anion transporting polypeptide (OATP)1B1/1B3, organic cation transporter (OCT)2, or organic anion transporter (OAT)1/3 but is a potential substrate of the efflux transporter P-glycoprotein (P-gp). Additionally, zanubrutinib is neither an inhibitor of P-gp at concentrations up to 10.0 μM nor an inhibitor of BCRP, OATP1B1, OATP1B3, OAT1, and OAT3 at concentrations up to 5.0 μM. The in vitro results with CYPs and transporters were correlated with the available clinical DDIs using basic models and mechanistic static models. Zanubrutinib is not likely to be involved in transporter-mediated DDIs. CYP3A inhibitors and inducers may impact systemic exposure of zanubrutinib. Dose adjustments may be warranted depending on the potency of CYP3A modulators.

Evobrutinib, a covalent Bruton's tyrosine kinase inhibitor: Mass balance, elimination route, and metabolism in healthy participants

The highly selective, covalent Bruton's tyrosine kinase inhibitor evobrutinib is under investigation for treatment of patients with multiple sclerosis (MS). Early clinical studies in healthy participants and patients with relapsing MS indicated that evobrutinib is well-tolerated and effective. We undertook a mass balance study in six men who received a single 75-mg oral dose of evobrutinib containing ~ 3.6 MBq (100 μCi) 14 C-evobrutinib, to determine the absorption, metabolic pathways, and routes of excretion of evobrutinib. The primary objectives of this phase I study (NCT03725072) were to (1) determine the rates and routes of total radioactivity excretion, including the mass balance of total drug-related radioactivity in urine and feces, (2) assess the pharmacokinetics (PKs) of total radioactivity in blood and plasma, and (3) characterize the plasma PKs of evobrutinib. Exploratory end points included identifying and quantifying evobrutinib and its metabolites in plasma and excreta (urine and feces) and exploring key biotransformation pathways and clearance mechanisms. Evobrutinib was primarily eliminated in feces (arithmetic mean percentage, SD, 71.0, 2.1) and, to a lesser extent, in urine (20.6, 2.0), with most of the total radioactivity (85.3%) excreted in the first 72 h after administration. No unchanged evobrutinib was detected in excreta. Evobrutinib was rapidly absorbed and substantially metabolized upon absorption. Only one major metabolite M463-2 (MSC2430422) was identified in plasma above the 10% of total drug exposure threshold, which classifies M463-2 (MSC2430422) as a major metabolite according to the US Food and Drug Administration (FDA; metabolites in safety testing [MIST]) and the European Medicines Agency (EMA; International Conference on Harmonization [ICH] M3). These results support further development of evobrutinib and may help inform subsequent investigations.

Discovery and evolution of 12N-substituted aloperine derivatives as anti-SARS-CoV-2 agents through targeting late entry stage

So far, there is still no specific drug against COVID-19. Taking compound 1 with anti-EBOV activity as the lead, fifty-four 12N-substituted aloperine derivatives were synthesized and evaluated for the anti-SARS-CoV-2 activities using pseudotyped virus model. Among them, 8a exhibited the most potential effects against both pseudotyped and authentic SARS-CoV-2, as well as SARS-CoV and MERS-CoV, indicating a broad-spectrum anti-coronavirus profile. The mechanism study disclosed that 8a might block a late stage of viral entry, mainly via inhibiting host cathepsin B activity rather than directly targeting cathepsin B protein. Also, 8a could significantly reduce the release of multiple inflammatory cytokines in a time- and dose-dependent manner, such as IL-6, IL-1β, IL-8 and MCP-1, the major contributors to cytokine storm. Therefore, 8a is a promising agent with the advantages of broad-spectrum anti-coronavirus and anti-cytokine effects, thus worthy of further investigation.

Discovery of an Orally Bioavailable Small-Molecule Inhibitor for the β-Catenin/B-Cell Lymphoma 9 Protein-Protein Interaction

Aberrant activation of Wnt/β-catenin signaling is strongly associated with many diseases including cancer invasion and metastasis. Small-molecule targeting of the central signaling node of this pathway, β-catenin, is a biologically rational approach to abolish hyperactivation of β-catenin signaling but has been demonstrated to be a difficult task. Herein, we report a drug-like small molecule, ZW4864, that binds with β-catenin and selectively disrupts the protein-protein interaction (PPI) between B-cell lymphoma 9 (BCL9) and β-catenin while sparing the β-catenin/E-cadherin PPI. ZW4864 dose-dependently suppresses β-catenin signaling activation, downregulates oncogenic β-catenin target genes, and abrogates invasiveness of β-catenin-dependent cancer cells. More importantly, ZW4864 shows good pharmacokinetic properties and effectively suppresses β-catenin target gene expression in the patient-derived xenograft mouse model. This study offers a selective chemical probe to explore β-catenin-related biology and a drug-like small-molecule β-catenin/BCL9 disruptor for future drug development.

Pharmacokinetics and safety of niraparib in patients with moderate hepatic impairment

PURPOSE

The purpose of this study is to characterize niraparib pharmacokinetics (PK) and safety in patients with normal hepatic function (NHF) versus moderate hepatic impairment (MHI).

METHODS

Patients with advanced solid tumors were stratified by NHF or MHI (National Cancer Institute-Organ Dysfunction Working Group criteria [bilirubin > 1.5-3 × upper limit of normal and any aspartate aminotransferase elevation]). In the PK phase, all patients received one 300 mg dose of niraparib. In the extension phase, patients with MHI received niraparib 200 mg daily; patients with NHF received 200 or 300 mg based on weight (< 77 kg, ≥ 77 kg)/platelets (< 150,000/µL, ≥ 150,000/µL). PK parameters included maximum concentration (C_max), area under the curve to last measured concentration (AUC_last) and extrapolated to infinity (AUC_inf). Safety was assessed in both phases. Exposure-response (E-R) modeling was used to predict MHI effects on exposure and safety of niraparib doses ≤ 200 mg or 300/200 mg or 200/100 mg weight/platelet regimens.

RESULTS

In the PK phase (NHF, n = 9; MHI, n = 8), mean niraparib C_max was 7% lower in patients with MHI versus NHF. Mean exposure (AUC_last, AUC_inf) was increased by 45% and 56%, respectively, in patients with MHI without impacting tolerability. In the extension phase (NHF, n = 8; MHI, n = 7), the overall safety profile was consistent with previous trials. In patients with MHI, E-R modeling predicted niraparib 200 mg reduced Grade ≥ 3 thrombocytopenia incidence, whereas a 200/100 mg regimen yielded exposures below efficacy-associated levels in 15% of patients.

CONCLUSION

These findings support adjusting the 300 mg niraparib starting dose to 200 mg QD in patients with MHI.

TRIAL REGISTRATION

NCT03359850; registered December 2, 2017.

Apoferritin/Vandetanib Association Is Long-Term Stable But Does Not Improve Pharmacological Properties of Vandetanib

A tyrosine kinase inhibitor, vandetanib (Van), is an anticancer drug affecting the signaling of VEGFR, EGFR and RET protooncogenes. Van is primarily used for the treatment of advanced or metastatic medullary thyroid cancer; however, its usage is significantly limited by side effects, particularly cardiotoxicity. One approach to minimize them is the encapsulation or binding of Van in- or onto a suitable carrier, allowing targeted delivery to tumor tissue. Herein, we constructed a nanocarrier based on apoferritin associated with Van (ApoVan). Based on the characteristics obtained by analyzing the average size, the surface ζ-potential and the polydispersive index, ApoVan nanoparticles exhibit long-term stability and maintain their morphology. Experiments have shown that ApoVan complex is relatively stable during storage. It was found that Van is gradually released from its ApoVan form into the neutral environment (pH 7.4) as well as into the acidic environment (pH 6.5). The effect of free Van and ApoVan on neuroblastoma and medullary thyroid carcinoma cell lines revealed that both forms were toxic in both used cell lines, and minimal differences between ApoVan and Van were observed. Thus, we assume that Van might not be encapsulated into the cavity of apoferritin, but instead only binds to its surface.

Novel CK2-Specific Pt(II) Compound Reverses Cisplatin-Induced Resistance by Inhibiting Cancer Cell Stemness and Suppressing DNA Damage Repair in Non-small Cell Lung Cancer Treatments

Cancer stem cells (CSCs) have a pivotal impact in drug resistance, tumor metastasis, and progression of various cancer entities, including in non-small cell lung cancer (NSCLC). A CK2 inhibitor HY1 was found to show potent CSC inhibitory effects in A549 cells. By taking advantage of inherent CK2 specificity and CSC inhibition of HY1, a Pt(II) agent (HY1-Pt) was developed by conjugation of HY1 with an active Pt(II) unit to reverse cisplatin-induced resistance in A549/cDDP cell treatment. In vitro biological studies indicated that HY1-Pt can target CK2, suppress DNA damage repair, reinforce cellular accumulation of platinum, and reverse resistance apart from effectively inhibiting CSCs through Wnt/β-catenin signal pathway in A549/cDDP cells. Significantly, HY1-Pt presented an acceptable pharmacokinetic behavior and exhibited higher tumor growth inhibitory efficacy than cisplatin either in A549 or A549/cDDP xenograft models with low toxicity. Overall, HY1-Pt is a promising drug candidate for NSCLC treatment.

Discovery of Acyl-sulfonamide Nav1.7 Inhibitors GDC-0276 and GDC-0310

Nav1.7 is an extensively investigated target for pain with a strong genetic link in humans, yet in spite of this effort, it remains challenging to identify efficacious, selective, and safe inhibitors. Here, we disclose the discovery and preclinical profile of GDC-0276 (1) and GDC-0310 (2), selective Nav1.7 inhibitors that have completed Phase 1 trials. Our initial search focused on close-in analogues to early compound 3. This resulted in the discovery of GDC-0276 (1), which possessed improved metabolic stability and an acceptable overall pharmacokinetics profile. To further derisk the predicted human pharmacokinetics and enable QD dosing, additional optimization of the scaffold was conducted, resulting in the discovery of a novel series of N-benzyl piperidine Nav1.7 inhibitors. Improvement of the metabolic stability by blocking the labile benzylic position led to the discovery of GDC-0310 (2), which possesses improved Nav selectivity and pharmacokinetic profile over 1.

Population Pharmacokinetic Analysis of the BTK Inhibitor Zanubrutinib in Healthy Volunteers and Patients With B-Cell Malignancies

Zanubrutinib is a potent, second-generation Bruton's tyrosine kinase inhibitor that is currently being investigated in patients with B-cell malignancies and recently received accelerated approval in the United States for treatment of relapsed/refractory mantle cell lymphoma. The objective of this analysis was to develop a population pharmacokinetic (PK) model to characterize the PKs of zanubrutinib and identify the potential impact of intrinsic and extrinsic covariates on zanubrutinib PK. Data across nine clinical studies of patients with B-cell malignancies and data of healthy volunteers (HVs) were included in this analysis, at total daily doses ranging from 20 to 320 mg. In total, 4,925 zanubrutinib plasma samples from 632 subjects were analyzed using nonlinear mixed-effects modeling. Zanubrutinib PKs were adequately described by a two-compartment model with sequential zero-order then first-order absorption, and first-order elimination. A time-dependent residual error model was implemented in order to better capture the observed maximum concentration variability in subjects. Baseline alanine aminotransferase and health status (HVs or patients with B-cell malignancies) were identified as statistically significant covariates on the PKs of zanubrutinib. These factors are unlikely to be clinically meaningful based on a sensitivity analysis. No statistically significant differences in the PKs of zanubrutinib were observed based on age, sex, race (Asian, white, and other), body weight, mild or moderate renal impairment (creatinine clearance ≥ 30 mL/minute as estimated by Cockcroft-Gault), baseline aspartate aminotransferase, bilirubin, tumor type, or use of acid-reducing agents (including proton pump inhibitors). These results support that no dose adjustment is considered necessary based on the aforementioned factors.

First-in-human imaging and kinetic analysis of vesicular acetylcholine transporter density in the heart using [18F]FEOBV PET

In contrast to cardiac sympathetic activity which can be assessed with established PET tracers, there are currently no suitable radioligands to measure cardiac parasympathetic (cholinergic) activity. A radioligand able to measure cardiac cholinergic activity would be an invaluable clinical and research tool since cholinergic dysfunction has been associated with a wide array of pathologies (e.g., chronic heart failure, myocardial infarction, arrythmias). [18F]Fluoroethoxybenzovesamicol (FEOBV) is a cholinergic radiotracer that has been extensively validated in the brain. Whether FEOBV PET can be used to assess cholinergic activity in the heart is not known. Hence, this study aimed to evaluate the properties of FEOBV for cardiac PET imaging and cholinergic activity mapping. PET data were collected for 40 minutes after injection of 230 ± 50 MBq of FEOBV in four healthy participants (1 female; Age: 37 ± 10; BMI: 25 ± 2). Dynamic LV time activity curves were fitted with Logan graphical, 1-tissue compartment, and 2-tissue compartment models, yielding similar distribution volume estimates for each participant. Our initial data show that FEOBV PET has favorable tracer kinetics for quantification of cholinergic activity and is a promising new method for assessing parasympathetic function in the heart.

Nanoencapsulated hybrid compound SA-2 with long-lasting intraocular pressure-lowering activity in rodent eyes

Purpose

Glaucoma is a neurodegenerative disease of the eye with an estimated prevalence of more than 111.8 million patients worldwide by 2040, with at least 6 to 8 million projected to become bilaterally blind. Clinically, the current method of slowing glaucomatous vision loss is to reduce intraocular pressure (IOP). In this manuscript, we describe the in vitro cytoprotective and in vivo long lasting IOP-lowering activity of the poly D, L-lactic-co-glycolic acid (PLGA) nanoparticle-encapsulated hybrid compound SA-2, possessing nitric oxide (NO) donating and superoxide radical scavenging functionalities.

Methods

Previously characterized primary human trabecular meshwork (hTM) cells were used for the study. hTM cells were treated with SA-2 (100 µM, 200 µM, and 1,000 µM), SA-2 PLGA-loaded nanosuspension (SA-2 NPs, 0.1%), or vehicle for 30 min. Cyclic guanosine monophosphate (cGMP) and super oxide dismutase (SOD) levels were analyzed using commercial kits. In another experiment, hTM cells were pretreated with tert-butyl hydrogen peroxide (TBHP, 300 µM) for 30 min followed by treatment with escalating doses of SA-2 for 24 h, and CellTiter 96 cell proliferation assay was performed. For the biodistribution study, the cornea, aqueous humor, vitreous humor, retina, choroid, and sclera were collected after 1 h of administration of a single eye drop (30 μl) of SA-2 NPs (1% w/v) formulated in PBS to rat (n = 6) eyes. Compound SA-2 was quantified using high performance liquid chromatography /mass spectrometry (HPLC/MS). For the IOP-lowering activity study, a single SA-2 NPs (1%) eye drop was instilled in normotensive rats eyes and in the IOP-elevated rat eyes (n = 3/group, in the Morrison model of glaucoma), or Ad5TGFβ2-induced ocular hypertensive (OHT) mouse eyes (n = 5/group). IOP was measured at various time points up to 72 h, and the experiment was repeated in triplicate. Mouse aqueous humor outflow facility was determined with multiple flow-rate infusion and episcleral venous pressure estimated with manometry.

Results

SA-2 upregulated cGMP levels (six- to ten-fold) with an half maximal effective concentration (EC50) of 20.3 µM in the hTM cells and simultaneously upregulated (40-fold) the SOD enzyme when compared with the vehicle-treated hTM cells. SA-2 also protected hTM cells from TBHP-induced decrease in cell survival with an EC50 of 0.38 µM. A single dose of slow-release SA-2 NPs (1% w/v) delivered as an eye drop significantly lowered IOP (by 30%) in normotensive and OHT rodent eyes after 3 h post-dose, with the effect lasting up to 72 h. A statistically significant increase in aqueous outflow facility and a decrease in episcleral venous pressure was observed in rodents at this dose at 54 h.

Conclusions

Hybrid compound SA-2 upregulated cGMP in hTM cells, increased outflow facility and decreased IOP in rodent models of OHT. Compound SA-2 possessing an antioxidant moiety provided additive cytoprotective activity to oxidatively stressed hTM cells by scavenging reactive oxygen species (ROS) and increasing SOD enzyme activity. Additionally, the PLGA nanosuspension formulation (SA-2 NPs) provided longer duration of IOP-lowering activity (up to 3 days) in comparison with the free non-encapsulated SA-2 drug. The data have implications for developing novel, non-prostaglandin therapeutics for IOP-lowering and cytoprotective effects with the possibility of an eye drop dosing regimen of once every 3 days for patients with glaucoma.

Silk industry waste protein: isolation, purification and fabrication of electrospun silk protein nanofibers as a possible nanocarrier for floating drug delivery

Amongst assorted regio-selective and targeted oral drug delivery strategies accepted for the gastro-retentive drug delivery system (GRDDS), the floating drug delivery system (FDDS) holds a major share as clinically accepted formulations. The major objective of the present investigation was to explore the silk industry waste protein, silk fibroin (SF) as a possible electrospun nanocarrier for the FDDS. In a nutshell, electrospinning (ES) is one of the flexible and astonishing strategies for the fabrication of porous electrospun nanofibers (NFs), which offers the potential to amend the floating profile, dissolution rate, solubility, and release patterns of the drug, etc as per compendial requirements. Looking at the prospects of floating SF-NFs preparation, we have isolated and lyophilized the SF from industrial waste cocoons and prepared drug-loaded SF single polymer nanofibers (SPN). Lafutidine (LF) being a good candidate for GRDDS selected as a model drug, which is an excellent proton pump inhibitor, mainly used in the treatment of gastric ulcers. Finally, the obtained LF loaded SF-NFs (LF-SF-NFs) were successfully analyzed for physicochemical characteristics, porosity, swelling index, antioxidant activity, mucoadhesion strength, floating properties, enzymatic degradation, and accelerated stability study, etc. Further, these LF-SF-NFs were evaluated for percent drug content, weight variation, in-vitro dissolution in 0.1 N hydrochloric acid (HCl, pH:1.2) and fasted state simulated gastric fluid (FSSGF), and accelerated stability study. It has shown significant floating time >18 h, about 99% ± 0.58% floating buoyancy with sustained release up to 24 h. LF-SF-NFs showed good compatibility, entrapment efficiency, antioxidant activity, mucoadhesion strength, enzymatic degradation, and long term stability. Soon, the essential floating and drug release profiles can claim single polymer (SF) based electrospun protein NFs as a possible novel oral nanocarrier for FDDS.