Optimal biological dose selection in dose-finding trials with model-assisted designs based on efficacy and toxicity: a simulation study

With the emergence of molecular targeted agents and immunotherapies in anti-cancer treatment, a concept of optimal biological dose (OBD), accounting for efficacy and toxicity in the framework of dose-finding, has been widely introduced into phase I oncology clinical trials. Various model-assisted designs with dose-escalation rules based jointly on toxicity and efficacy are now available to establish the OBD, where the OBD is generally selected at the end of the trial using all toxicity and efficacy data obtained from the entire cohort. Several measures to select the OBD and multiple methods to estimate the efficacy probability have been developed for the OBD selection, leading to many options in practice; however, their comparative performance is still uncertain, and practitioners need to take special care of which approaches would be the best for their applications. Therefore, we conducted a comprehensive simulation study to demonstrate the operating characteristics of the OBD selection approaches. The simulation study revealed key features of utility functions measuring the toxicity-efficacy trade-off and suggested that the measure used to select the OBD could vary depending on the choice of the dose-escalation procedure. Modelling the efficacy probability might lead to limited gains in OBD selection.

Safety, Tolerability, and Pharmacokinetics of an Oral Small Molecule Inhibitor of IL-17A (LY3509754): A Phase I Randomized Placebo-Controlled Study

For some patients with psoriasis, orally administered small molecule inhibitors of interleukin (IL)-17A may represent a convenient alternative to IL-17A-targeting monoclonal antibodies. This first-in-human study assessed the safety, tolerability, pharmacokinetics (PKs), and peripherally circulating IL-17A target engagement profile of single or multiple oral doses of the small molecule IL-17A inhibitor LY3509754 (NCT04586920). Healthy participants were randomly assigned to receive LY3509754 or placebo in sequential escalating single ascending dose (SAD; dose range 10-2,000 mg) or multiple ascending dose (MAD; dose range 100-1,000 mg daily for 14 days) cohorts. The study enrolled 91 participants (SAD, N = 51 and MAD, N = 40) aged 21-65 years (71% men). LY3509754 had a time to maximum concentration (Tmax) of 1.5-3.5 hours, terminal half-life of 11.4-19.1 hours, and exhibited dose-dependent increases in exposure. LY3509754 had strong target engagement, indicated by elevated plasma IL-17A levels within 12 hours of dosing. Four participants from the 400-mg (n = 1) and 1,000-mg (n = 3) MAD cohorts experienced increased liver transaminases or acute hepatitis (onset ≥ 12 days post-last LY3509754 dose), consistent with drug-induced liver injury (DILI). One case of acute hepatitis was severe, resulted in temporary hospitalization, and was classified as a serious adverse event. No adverse effects on other major organ systems were observed. Liver biopsies from three of the four participants revealed lymphocyte-rich, moderate-to-severe lobular inflammation. We theorize that the DILI relates to an off-target effect rather than IL-17A inhibition. In conclusion, despite strong target engagement and a PK profile that supported once-daily administration, this study showed that oral dosing with LY3509754 was poorly tolerated.

ACD856, a novel positive allosteric modulator of Trk receptors, single ascending doses in healthy subjects: Safety and pharmacokinetics

PURPOSE

AlzeCure Pharma AB is developing novel positive allosteric modulators of Trk-receptors for treatment of Alzheimer's disease, depression, other psychiatric conditions and other disorders where cognition is impaired. The preceding candidate drug ACD855 was shown to have a too long half-life in humans to allow further development. To de-risk the development of the follow-up compound ACD856, the oral single ascending dose study of ACD856 in humans was preceded by an intravenous microdose study, assessing the elimination half-life in plasma.

METHODS

A phase 0 study with a microdose of ACD856 (0.100 mg), was conducted in six healthy male subjects all receiving ACD856. Sequentially, a randomized, placebo-controlled, double-blind Phase I single ascending oral dose study (1 - 150 mg) was conducted, including 56 healthy subjects. Both studies assessed the safety and tolerability, as well as the PK properties of ACD856 after single dose intravenous and oral administration.

RESULTS

ACD856 was well tolerated with no treatment emergent, or dose related adverse events or other safety assessments. In the microdose study, ACD856 exhibited a bi-exponential plasma decline, low distribution volume, low plasma clearance with a half-life of approximately 20 hours. Orally, ACD856 exhibited rapid absorption, an almost complete bioavailability and a dose proportional increase in exposure. While the Cmax was lowered and delayed by food intake, the effect on plasma half-life and the overall bioavailability was low. No renal elimination of ACD856 was detected.

CONCLUSION

The prediction proved accurate demonstrating the value of conducting a microdose study prior to ascending dose studies.

TRIAL REGISTRATION

NCT05783830 March 24, 2023 (microdose study, retrospectively registered) and NCT05077631 October 14, 2021 (single ascending dose study).

Bayesian model averaging of longitudinal dose-response models

Selecting a safe and clinically beneficial dose can be difficult in drug development. Dose justification often relies on dose-response modeling where parametric assumptions are made in advance which may not adequately fit the data. This is especially problematic in longitudinal dose-response models, where additional parametric assumptions must be made. This paper proposes a class of longitudinal dose-response models to be used in the Bayesian model averaging paradigm which improve trial operating characteristics while maintaining flexibility a priori. A new longitudinal model for non-monotonic longitudinal profiles is proposed. The benefits and trade-offs of the proposed approach are demonstrated through a case study and simulation.

The psychomotor, reinforcing, and discriminative stimulus effects of synthetic cathinone mexedrone in male mice and rats

The chronic use of the novel synthetic cathinone mexedrone, like other psychoactive drugs, can be considered addictive, with a high potential for abuse and the ability to cause psychological dependence in certain users. However, little is known about the neurobehavioral effects of mexedrone in association with its potential for abuse. We investigated the abuse potential for mexedrone abuse through multiple behavioral tests. In addition, serotonin transporter (SERT) levels were measured in the synaptosome of the dorsal striatum, and serotonin (5-HT) levels were measured in the dorsal striatum of acute mexedreone (50 mg/kg)-treated mice. To clarify the neuropharmacological mechanisms underlying the locomotor response of mexedrone, the 5-HT2A receptor antagonist M100907 (0.5 or 1.0 mg/kg) was administered prior to the acute injection of mexedrone in the locomotor activity experiment in mice. Mexedrone (10-50 mg/kg) produced a significant place preference in mice and mexedrone (0.1-0.5 mg/kg/infusion) maintained self-administration behavior in rats in a dose-dependent manner. In the drug discrimination experiment, mexedrone (5.6-32 mg/kg) was fully substituted for the discriminative stimulus effects of cocaine in rats. Mexedrone increased locomotor activity, and these effects were reversed by pretreatment with M100907. Acute mexedrone significantly increased c-Fos expression in the dorsal striatum and decreased SERT levels in the synaptosome of the dorsal striatum of mice, resulting in an elevation of 5-HT levels. Taken together, our results provide the possibility that mexedrone has abuse potential, which might be mediated, at least in part, by the activation of the serotonergic system in the dorsal striatum.

Benchmark dose modeling for epidemiological dose-response assessment using prospective cohort studies

Benchmark dose (BMD) methodology has been employed as a default dose-response modeling approach to determine the toxicity value of chemicals to support regulatory chemical risk assessment. Especially, a relatively standardized BMD analysis framework has been established for modeling toxicological data regarding the formats of input data, dose-response models, definitions of benchmark response, and model uncertainty consideration. However, the BMD approach has not been well developed for epidemiological data mainly because of the diverse designs of epidemiological studies and various formats of data reported in the literature. Although most of the epidemiological BMD analyses were developed to solve a particular question, the methods proposed in two recent studies are able to handle cohort and case-control studies using summary data with consideration of adjustments for confounders. Therefore, the purpose of the present study is to investigate and compare the "effective count"-based BMD modeling approach and adjusted relative risk (RR)-based BMD analysis approach to identify an appropriate BMD modeling framework that can be generalized for analyzing published data of prospective cohort studies for BMD analysis. The two methods were applied to the same set of studies that investigated the association between bladder and lung cancer and inorganic arsenic exposure for BMD estimation. The results suggest that estimated BMDs and BMDLs are relatively consistent; however, with the consideration of established common practice in BMD analysis, modeling adjusted RR values as continuous data for BMD estimation is a more generalizable approach harmonized with the BMD approach using toxicological data.

Safety, Tolerability, and Pharmacokinetics of a Novel Oral Phosphodiesterase 4 Inhibitor, ME3183: First-in-Human Phase 1 Study

A novel, oral phosphodiesterase 4 (PDE4) inhibitor, ME3183, is under development for the treatment of psoriasis, atopic dermatitis, and other inflammatory diseases. To evaluate its safety, tolerability, and pharmacokinetics, double-blind, placebo-controlled, single ascending dose (SAD), and multiple ascending dose (MAD) phase 1 studies were conducted in 126 healthy adults. The food effect was evaluated in a randomized, open-label, crossover manner (n = 5). ME3183 was safe and tolerable up to 25 mg in the SAD part and up to 10 mg twice daily in the MAD part. Frequently observed treatment-emergent adverse events included diarrhea and headache, as commonly reported for approved PDE4 inhibitors, providing no novel safety concerns. Pharmacokinetic analysis showed dose-dependent increases in Cmax and AUC, with later tmax and longer t1/2 than apremilast, an approved PDE4 inhibitor. The food effect study showed slightly decreased systemic exposure. In the MAD part, plasma exposure levels of ME3183 were higher even at the minimal dose (2.5 mg twice daily) than the estimated therapeutically effective level. These results show the safe profile of ME3183 and support further studies to confirm the safety and efficacy of the drug in patients with psoriasis and other inflammatory diseases.

Dopaminergic modulation of sensitivity to immediate and delayed punishment during decision-making

Effective decision-making involves careful consideration of all rewarding and aversive outcomes. Importantly, negative outcomes often occur later in time, leading to underestimation, or "discounting," of these consequences. Despite the frequent occurrence of delayed outcomes, little is known about the neurobiology underlying sensitivity to delayed punishment during decision-making. The Delayed Punishment Decision-making Task (DPDT) addresses this by assessing sensitivity to delayed versus immediate punishment in rats. Rats initially avoid punished reinforcers, then select this option more frequently when delay precedes punishment. We used DPDT to examine effects of acute systemic administration of catecholaminergic drugs on sensitivity to delayed punishment in male and female adult rats. Cocaine did not affect choice of rewards with immediate punishment but caused a dose-dependent reduction in choice of delayed punishment. Neither activation nor blockade of D1-like dopamine receptor affected decision-making, but activation of D2-like dopamine receptors reduced choice of delayed punishment. D2 blockade did not attenuate cocaine's effects on decision-making, suggesting that cocaine's effects are not dependent on D2 receptor activation. Increasing synaptic norepinephrine via atomoxetine also reduced choice of delayed (but not immediate) punishment. Notably, when DPDT was modified from ascending to descending pre-punishment delays, these drugs did not affect choice of delayed or immediate punishment, although high-dose quinpirole impaired behavioral flexibility. In summary, sensitivity to delayed punishment is regulated by both dopamine and norepinephrine transmission in task-specific fashion. Understanding the neurochemical modulation of decision-making with delayed punishment is a critical step toward treating disorders characterized by aberrant sensitivity to negative consequences.

Safety, tolerability, pharmacokinetics and neutrophil elastase inhibitory effects of Sivelestat: A randomized, double-blind, placebo-controlled single- and multiple-dose escalation study in Chinese healthy subjects

BACKGROUND AND OBJECTIVE

Neutrophil elastase has been identified as a potential therapeutic target for acute lung injury or acute respiratory distress syndrome, and Sivelestat is a selective, reversible and competitive neutrophil elastase inhibitor. This study was designed to investigate the safety, tolerability, pharmacokinetics and neutrophil elastase inhibitory effects of Sivelestat in healthy Chinese subjects.

METHODS

A randomized, double-blind, placebo-controlled single- and multiple-dose escalation clinical trial was carried out. Briefly, healthy volunteers in twelve cohorts with 8 per cohort received 1.0-20.2 mg/kg/h Sivelestat or placebo in an intravenous infusion manner for two hours, and healthy volunteers in four cohorts received two hours intravenous infusion of 2.0-5.0 mg/kg/h Sivelestat or placebo with an interval of twelve hours for seven times. The safety and tolerability were evaluated and serial blood samples were collected for pharmacokinetics and neutrophil elastase inhibitory effects analysis at the specified time-point.

RESULTS

A total of 128 subjects were enrolled and all participants completed the study except one. Sivelestat exhibited satisfactory safety and tolerability up to 20.2 mg/kg/h in single-dose cohorts and 5.0 mg/kg/h in multiple-dose cohorts. Even so, more attention should be paid to the safety risks when using high doses. The Cmax and AUC of Sivelestat increased in a dose dependent manner, and Tmax was similar for different dose cohorts. In multiple-dose cohorts, the plasma concentrations reached steady state 48 h after first administration and the accumulation of Cmax and AUC was not obvious. Furthermore, the Cmin_ss of 5.0 mg/kg/h dose cohort could meet the needs of clinical treatment. For some reason, the pharmacodynamics data revealed that the inhibitory effect of Sivelestat on neutrophil elastase content in healthy subjects was inconclusive.

CONCLUSION

Sivelestat was safe and well tolerated with appropriate pharmacokinetic parameters, which provided support for more diverse dosing regimen in clinical application.

CLINICAL TRIAL REGISTRATION

www.chinadrugtrials.org.cn identifier is CTR20210072.

Pharmacokinetics, pharmacodynamics, and safety of fesomersen, a novel antisense inhibitor of factor XI, in healthy Chinese, Japanese, and Caucasian volunteers

The inhibition of coagulation factor XI (FXI) presents an attractive approach for anticoagulation as it is not expected to increase the risk of clinically relevant bleeding and is anticipated to be at least as effective as currently available anticoagulants. Fesomersen is a conjugated antisense oligonucleotide that selectively inhibits the expression of FXI. The article describes three clinical studies that investigated the safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of fesomersen after subcutaneous (s.c.) injection to healthy participants. The studies included participants from diverse ethnic backgrounds (Caucasian, Japanese, and Chinese). Fesomersen demonstrated good safety and tolerability in all three studies. No major bleeding events were observed. After single-dose s.c. injection, fesomersen was rapidly absorbed into the systemic circulation, with maximum fesomersen-equivalent (fesomersen-eq) concentrations (Cmax) in plasma observed within a few hours. After reaching Cmax, plasma fesomersen-eq concentrations declined in a biphasic fashion. The PD analyses showed that the injection of fesomersen led to dose-dependent reductions in FXI activity and increases in activated partial thromboplastin time (aPTT). The maximum observed PD effects were reached between Day 15 and 30, and FXI activity and aPTT returned to near-baseline levels by Day 90 after a single dose. The PK/PD profiles after a single injection were similar among the various ethnic groups. Collectively, the study results suggest that fesomersen has a favorable safety profile and predictable and similar PK and PD profiles across Chinese, Japanese, and Caucasian participants.

A phase 1 trial of AP30663, a KCa2 channel inhibitor in development for conversion of atrial fibrillation

AIMS

AP30663 is a novel compound under development for pharmacological conversion of atrial fibrillation by targeting the small conductance Ca2+ activated K+ (KCa2) channel. The aim of this extension phase 1 study was to test AP30663 at higher single doses compared to the first-in-human trial.

METHODS

Sixteen healthy male volunteers were randomized into 2 cohorts: 6- and 8-mg/kg intravenous single-dose administration of AP30663 vs. placebo. Safety, pharmacokinetic and pharmacodynamic data were collected.

RESULTS

AP30663 was associated with mild and transient infusion site reactions with no clustering of other adverse events but with an estimated maximum mean QTcF interval prolongation of 45.2 ms (95% confidence interval 31.5-58.9) in the 6 mg/kg dose level and 50.4 ms (95% confidence interval 36.7-64.0) with 8 mg/kg. Pharmacokinetics was dose proportional with terminal half-life of around 3 h.

CONCLUSION

AP30663 in doses up to 8 mg/kg was associated with mild and transient infusion site reactions and an increase of the QTcF interval. Supporting Information support that the QTc effect may be explained by an off-target inhibition of the IKr channel.

A Randomized, Phase 3, Double-Blind, Crossover Comparison of Multilayer, Extended-Release Methylphenidate (PRC-063), and Lisdexamfetamine in the Driving Performance of Young Adults With ADHD

OBJECTIVE

To compare PRC-063 (multilayer-release methylphenidate) and lisdexamfetamine dimesylate (LDX) on the driving performance of young adults with attention deficit hyperactivity disorder (ADHD) in a randomized, double-blind, crossover study.

METHOD

Following up to 21 days of each treatment in each treatment course (PRC-063/LDX or LDX/PRC-063), subjects completed a 15-hour driving simulator laboratory assessment. The primary outcome measure was the Tactical Driving Quotient (TDQ) and the Clinical Global Impressions-Improvement (CGI-I) scale was a secondary outcome measure.

RESULTS

Forty-four subjects completed the study. PRC-063 and LDX had equivalent effects on driving performance through a 15-hour time period (least square mean difference -0.3 [standard error 1.08], 95% confidence interval [-2.4, 1.8], p = .793). Consistent improvement in CGI-I was observed. The incidence of treatment-emergent adverse events was similar for each treatment sequence.

CONCLUSIONS

PRC-063 and LDX had comparable effects on driving performance, from 1 through 15 hours, the last time point measured.

Pharmacokinetics, pharmacodynamics, and safety of frunexian in healthy Chinese volunteer adults: A randomized dose-escalation phase I study

The purpose of this study was to evaluate the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of frunexian (formerly known as EP-7041 and HSK36273) injection, a small molecule inhibitor of activated coagulation factor XI (FXIa), in healthy Chinese adult volunteers. This study was a randomized, placebo- and positive-controlled, sequential, ascending-dose (0.3/0.6/1.0/1.5/2.25 mg/kg/h) study of 5-day continuous intravenous infusions of frunexian. Frunexian administration exhibited an acceptable safety profile with no bleeding events. Steady state was rapidly reached with a median time ranging from 1.02 to 1.50 h. The mean half-life ranged from 1.15 to 1.43 h. Frunexian plasma concentration at a steady state and area under the concentration-time curve exhibited dose-proportional increases. The dose-escalation study of frunexian demonstrated its progressively enhanced capacities to prolong activated partial thromboplastin time (aPTT) and inhibit FXIa activity. The correlations between PK and PD biomarkers (aPTT/baseline and FXI clotting activity/baseline) were described by the two Emax models, with the EC50 values of 8940 and 1300 ng/mL, respectively. Frunexian exhibits good safety and PK/PD properties, suggesting it is a promising candidate for anticoagulant drug.

Electroencephalographic profile of Salvia amarissima Ortega and amarisolide A in the absence and presence of PTZ-induced seizures in mice

Salvia amarissima Ortega is a plant used in traditional medicine to treat CNS's affections. Despite its depressant properties in anxiety and fibromyalgia, there is no scientific evidence about its capability to control seizure activity. This study aimed to investigate the effects of the S. amarissima aqueous extract (SAAE) and its metabolite amarisolide A (AMA) on the electrocorticographic (ECoG) activity. The ECoG profiles were previously and concurrently analyzed to the pentylenetetrazole (85 mg/kg, i.p.)-induced seizure behavior after thirty min of the administration of several doses of the SAAE (1, 10, 30, and 100 mg/kg, i.p.) and two doses of AMA (0.5 and 1 mg/kg, i.p.). A dosage of AMA (1 mg/kg,i.p.) was selected to explore a possible mechanism of action by using antagonists of inhibitory receptors such as GABAA (picrotoxin, 1 mg/kg, i.p.) or 5-HT1A of serotonin (WAY100635, 1 mg/kg, i.p.). Significant changes in the frequency bands and the spectral power were observed after the treatment alone. Additionally, SAAE and AMA produced significant and dose-dependent anticonvulsant effects by reducing the incidence and severity of seizures and increasing latency or survival. Both antagonists prevented the effects of AMA in the severity score of seizures and survival during the tonic-clonic seizures. In conclusion, our preclinical data support that S. amarissima possesses anticonvulsant properties, in part due to the presence of amarisolide A, mediated by different inhibitory mechanisms of action. Our scientific evidence suggests that this Salvia species and amarisolide A are potential neuroprotective alternatives to control seizures in epilepsy therapy.

Safety, tolerability, pharmacokinetic, pharmacodynamic and immunogenicity profiles of Exendin-4-IgG4-Fc in healthy subjects: A phase 1, single-centre, randomized, double-blind, dose escalation study

AIM

Novel long-acting drugs for type 2 diabetes mellitus may optimize patient compliance and glycaemic control. Exendin-4-IgG4-Fc (E4F4) is a long-acting glucagon-like peptide-1 receptor agonist. This first-in-human study investigated the safety, tolerability, pharmacokinetic, pharmacodynamic and immunogenicity profiles of a single subcutaneous injection of E4F4 in healthy subjects.

METHODS

This single-centre, randomized, double-blind, placebo-controlled phase 1 clinical trial included 96 subjects in 10 sequential cohorts that were provided successively higher doses of E4F4 (0.45, 0.9, 1.8, 3.15, 4.5, 6.3, 8.1, 10.35, 12.6 and 14.85 mg) or placebo (ChinaDrugTrials.org.cn: ChiCTR2100049732). The primary endpoint was safety and tolerability of E4F4. Secondary endpoints were pharmacokinetic, pharmacodynamic and immunogenicity profiles of E4F4. Safety data to day 15 after the final subject in a cohort had been dosed were reviewed before commencing the next dose level.

RESULTS

E4F4 was safe and well tolerated among healthy Chinese participants in this study. There was no obvious dose-dependent relationship between frequency, severity or causality of treatment-emergent adverse events. Cmax and area under the curve of E4F4 were dose proportional over the 0.45-14.85 mg dose range. Median Tmax and t1/2 ranged from 146 to 210 h and 199 to 252 h, respectively, across E4F4 doses, with no dose-dependent trends. For the intravenous glucose tolerance test, area under the curve of glucose in plasma from time 0 to 180 min showed a dose-response relationship in the 1.8-10.35 mg dose range, with an increased response at the higher doses.

CONCLUSION

E4F4 exhibited an acceptable safety profile and linear pharmacokinetics in healthy subjects. The recommended phase 2 dose is 4.5-10.35 mg once every 2 weeks.

First-in-human study of CPL207280, a novel G-protein-coupled receptor 40/free fatty acid receptor 1 agonist, in healthy volunteers after single and multiple administration

AIM

To assess the safety, tolerability and pharmacokinetic (PK) profile of single and multiple doses of CPL207280, a new G-protein-coupled receptor 40 agonist developed to treat type 2 diabetes (T2D).

METHODS

The phase 1 study in healthy volunteers (White, age 18-55 years, body mass index 18.5-29.9 kg/m2 ) was performed after single (24 subjects, 5-480 mg) and multiple (32 subjects, 60-480 mg) once-daily administration of CPL207280.  The effect of food intake and interaction with metformin were evaluated in additional cohort (12 subjects, 120 mg). The primary objective was the safety and tolerability of CPL207280. Secondary objectives included PK and pharmacodynamic (PD) characteristics (glucose, insulin, C-peptide, proinsulin, glucagon levels) observed during the 14-day treatment period.

RESULTS

No deaths or serious adverse events (AEs) were reported. All reported AEs were classified as unrelated to the study product. No clinically significant differences in safety parameters were observed between cohorts and no food or metformin effect on safety parameters was identified. The ascending dose of CPL207280 caused an increase in the PK parameters maximum observed plasma concentration (Cmax ) or area under the plasma concentration-time curve up to 24 h. However, dose-normalized Cmax decreased with ascending dose. There was no relationship between the CPL207280 dose or prandial state and terminal elimination half-life and terminal elimination rate constant. No clear relationship between CPL207280 dose and PD area under the effect curve values was observed.

CONCLUSIONS

CPL207280 was found to be safe and well tolerated by healthy volunteers (with a low risk of hepatotoxicity) for up to 14 days of administration. The PK profile of CPL207280 supports single-daily administration and justifies further development of this therapy for patients with T2D.

Synthesis, biological evaluation and docking studies of N-substituted resveratrol derivatives

A total of 19 resveratrol derivatives, including 12 imines and 7 amines, were synthesized, among which compounds 1, 5, 6, 7', 11', and 13 are new compounds. The anti-inflammatory and antitumor activities of these compounds were evaluated in vitro. The results revealed that compounds 1, 6, 8', 12, and 12' exhibited significant inhibitory effects (> 50%) on NO production at the concentration of 10 μM and their NO production inhibitory activities have a significant concentration-dependent ability. Additionally, compounds 8' and 12' showed promising COX-2 inhibitory activity, and the molecular docking analysis indicated their stable binding to multiple amino acid residues within the active pocket of COX-2 through hydrogen bonding. Moreover, compound 12' exhibited inhibitory effects on various tumor cell lines and induced apoptosis in MCF-7 breast cancer cells, which was not observed with resveratrol alone. Therefore, the N-substituted structural modification of resveratrol would have possibly enhanced the bioactivity of resveratrol and facilitated its application.

Estimation of target occupancy in repeated dosing design studies using positron emission tomography: Biases due to target upregulation

Positron emission tomography (PET) has become indispensable in the quantification of target engagement by brain targeting medications. The relationship between the drug plasma concentration (or drug dose administered) and target occupancy determined during a PET occupancy study has provided valuable information for the assessment of novel pharmaceuticals in the early phases of drug development. Such information is also critical for the understanding of the mechanisms of action and side-effect profile of approved medication commonly used in the clinic. Occupancy studies conducted following repeated drug dosing (RD) can produce systematic differences from those conducted following single drug dose (SD), differences that have not been adequately explored. We have hypothesised that when differences are observed between RD and SD studies, they are related to changes in target density induced by repeated drug accumulation. We have developed a modified occupancy model to account for potential changes in target density and tested it on a sample dataset. We found that target upregulation can parsimoniously explain the differences in drug affinity estimated in SD and RD studies. Our findings have implications for the interpretation of RD occupancy data in the literature and the relationship between specific target occupancy levels and drug efficacy and tolerability.

Reporting and impact of subsequent cycle toxicities in oncology phase I clinical trials

BACKGROUND/AIMS

As oncology treatments evolve, classic assumptions of toxicity associated with cytotoxic agents may be less relevant, requiring new design strategies for trials intended to inform dosing strategies for agents that may be administered beyond a set number of defined cycles. We describe the overall incidence of dose-limiting toxicities during and after cycle 1, frequency of reporting subsequent cycle toxicities, and the impact of post-cycle 1 dose-limiting toxicities on conclusions drawn from oncology phase 1 clinical trials.

METHODS

We conducted a systematic review of subsequent cycle toxicities in oncology phase I clinical trials published in the Journal of Clinical Oncology from 2000 to 2020. We used chi-square tests and multivariate logistic regression to describe predictors of reporting subsequent cycle toxicity data.

RESULTS

From 2000 to 2020, we identified 489 articles reporting on therapeutic phase 1 clinical trials. Of these, 421 (86%) reported data regarding cycle 1 dose-limiting toxicities and 170 (35%) reported data on cycle 1 dose modifications. Of the trials that reported cycle 1 dose-limiting toxicities, the median percentage of patients that experienced cycle 1 dose-limiting toxicities was 8.89%. Only 47 (9.6%) publications reported on post-cycle 1 dose-limiting toxicities and only 92 (19%) reported on dose modifications beyond cycle 1. Of the trials that reported post-cycle 1 dose-limiting toxicities, the median percentage of patients that experienced post-cycle 1 dose-limiting toxicities was 14.8%. Among the 371 studies with a recommended phase 2 dose, 89% did not report whether post-cycle 1 toxicities impacted the recommended phase 2 dose. More recent year of publication was independently associated with reduced odds of reporting subsequent cycle toxicity.

CONCLUSION

Reporting of subsequent cycle toxicity is uncommon in oncology phase I clinical trial publications and becoming less common over time. Guidelines for reporting of phase I oncology clinical trials should expand to include toxicity data beyond the first cycle.

Safety, pharmacokinetics, and pharmacodynamics of anti-IL-4Rα antibody SHR-1819 in healthy subjects: A randomized, controlled phase I study

SHR-1819 is a novel anti-IL-4Rα monoclonal antibody currently under clinical development for use in patients with type 2 inflammatory diseases. In this randomized, double-blind, placebo-controlled, single-dose escalation phase I trial, we evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of SHR-1819 in healthy subjects. Subjects received a single subcutaneous injection of SHR-1819 or placebo, with dose escalation starting at 60 mg and subsequently increasing to 120, 240, 360, and 720 mg. A total of 42 eligible subjects were randomized, and 33 received SHR-1819 (1 subject in the 60 mg cohort and 8 subjects each in the 120, 240, 360 , and 720 mg cohorts) and 9 received placebo. SHR-1819 was well-tolerated, with the majority of adverse events being mild in severity. The exposure of SHR-1819 increased in a manner greater than proportionally with a dose range of 120 to 720 mg. The median Tmax was within 4-7 days (60-720 mg), and the mean half-life ranged from 2.88 to 5.97 days (120-720 mg). The clearance rate of SHR-1819 exhibited a decrease with increasing dose level. Administration of SHR-1819 resulted in a certain degree of reduction in the percentage change from baseline in concentrations of inflammatory biomarkers TARC/CCL17 and IgE, while the reduction of TARC/CCL17 concentrations showed a dose-dependent trend. More than half of the total subjects treated with SHR-1819 were reported antidrug antibody-negative. The preliminary data from this phase I study support further development of SHR-1819 for the treatment of type 2 inflammatory diseases.

BOIN-ETC: A Bayesian optimal interval design considering efficacy and toxicity to identify the optimal dose combinations

One of the primary objectives of a dose-finding trial for novel anti-cancer agent combination therapies, such as molecular targeted agents and immune-oncology therapies, is to identify optimal dose combinations that are tolerable and therapeutically beneficial for subjects in subsequent clinical trials. The goal differs from that of a dose-finding trial for traditional cytotoxic agents, in which the goal is to determine the maximum tolerated dose combinations. This paper proposes the new design, named 'BOIN-ETC' design, to identify optimal dose combinations based on both efficacy and toxicity outcomes using the waterfall approach. The BOIN-ETC design is model-assisted, so it is expected to be robust, and straightforward to implement in actual oncology dose-finding trials. These characteristics are quite valuable from a practical perspective. Simulation studies show that the BOIN-ETC design has advantages compared with the other approaches in the percentage of correct optimal dose combination selection and the average number of patients allocated to the optimal dose combinations across various realistic settings.

Flavonoids commonly induce hormetic responses

The present paper provides a new perspective of previously published findings by Siwak (Food Chem 141:1227-1241, 2013) which showed that 15 structurally diverse flavonoids reduced toxicity (i.e., enhanced cell viability) from hypochlorite using the MTT assay within a pre-conditioning experimental protocol, with each agent showing a similar biphasic concentration response relationship. We use this Commentary to point out that each of the concentration response relationships are consistent with the hormetic dose response. The paper of Siwak (Food Chem 141:1227-1241, 2013) is unique in that it provides a comparison of a relatively large number of agents using the identical experimental protocol.

Effects of morphine on conditioned place preference and pain are independent of uptake‑2

Morphine changes neurotransmitter release, including norepinephrine, dopamine, and serotonin. Decynium‑22 (D22) inhibits an alternative neurotransmitter removal pathway, namely uptake‑2. Uptake‑2 includes plasma membrane monoamine transporter (PMAT) and organic cation transporters that have a low affinity, but high capacity for uptake of various monoamines such as norepinephrine, dopamine, and serotonin. This study was done to assess the effect of uptake‑2 inhibition on morphine‑induced conditioned place preference (CPP) and analgesia. In this study, the effects of morphine and/or D22 on CPP were evaluated following intraperitoneal injection in mice. Afterward, changes in motor activity were evaluated by the open field test. Using the tail‑flick model, the effects of D22 and/or morphine were evaluated on the pain threshold. The results showed that 20 mg/kg of morphine induced a place preference response. D22, at the dose of 0.03 mg/kg, caused place avoidance, while at the dose of 0.3 mg/kg, it produced a notable place preference response. Co‑administration of D22 and morphine showed that morphine reversed the CPP aversion induced by D22 at the lowest dose. Motor activity did not alter. In the tail‑flick test, morphine, at the dose of 3 mg/kg but not 1 mg/kg, increased the pain threshold. D22 induced significant analgesic responses. Co‑administration of D22 and morphine caused considerable analgesic effects. The findings revealed that D22 induced both conditioned aversion and preference depending on the dose while morphine induced CPP. Both drugs produced analgesia.

[Effect of asiaticoside on systolic blood pressure and relaxation of isolated thoracic aorta of rats]

OBJECTIVE

To investigate the effect of asiaticoside on blood pressure and relaxation of thoracic aorta in rats and explore the underlying mechanism.

METHODS

SD rats treated with 50 and 100 mg/kg asiaticoside by daily gavage for 2 weeks were monitored for systolic blood pressure changes, and histological changes of the thoracic aorta were evaluated using HE staining. In isolated rat endothelium-intact and endothelium-denuded thoracic aorta rings, the effects of asiaticoside on relaxation of the aortic rings were tested at baseline and following norepinephrine (NE)- and KCl-induced constriction. The vascular relaxation effect of asiaticoside was further observed in NE-stimulated endothelium-intact rat aortic rings pretreated with L-nitroarginine methyl ester, indomethacin, zinc protoporphyrin Ⅸ, tetraethyl ammonium chloride, glibenclamide, barium chloride, Iberiotoxin, 4-aminopyridine, or TASK-1-IN-1. The aortic rings were treated with KCl and NE followed by increasing concentrations of CaCl2 to investigate the effect of asiaticoside on vasoconstriction induced by external calcium influx and internal calcium release.

RESULTS

Asiaticoside at 50 and 100 mg/kg significantly lowered systolic blood pressure in rats without affecting the thoracic aorta histomorphology. While not obviously affecting resting aortic rings with intact endothelium, asiaticoside at 100 mg/kg induced significant relaxation of the rings constricted by KCl and NE, but its effects differed between endothelium-intact and endothelium-denuded rings. In endothelium-intact aortic rings pretreated with indomethacin, ZnPP Ⅸ, barium chloride, glyburide, TASK-1-IN-1 and 4-aminopyridine, asiaticoside did not produce significant effect on NE-induced vasoconstriction, and tetraethylammonium, Iberiotoxin and L-nitroarginine methyl ester all inhibited the relaxation effect of asiaticoside. In KCland NE-treated rings, asiaticoside obviously inhibited CaCl2-induced vascular contraction.

CONCLUSION

Asiaticoside induces thoracic aorta relaxation by mediating high-conductance calcium-activated potassium channel opening, promoting nitric oxide release from endothelial cells and regulating Ca2+ influx and outflow, thereby reducing systolic blood pressure in rats.

The Effects of Chronic Naltrexone on Reinstatement of Opioid-Induced Drug-Seeking Behavior and Antinociception

Opioid addiction is a chronic relapsing disorder in which drug-seeking behavior during abstinence can be provoked by exposure to a µ-opioid receptor (MOR) agonist or opioid-associated cues. Opioid self-administration behavior in laboratory subjects can be reinstated by priming with MOR agonists or agonist-related stimuli, providing a procedure suitable for relapse-related studies. The opioid antagonist naltrexone has been forwarded as a medication that can forestall relapse and, in an extended-release formulation, has demonstrated some treatment success. However, chronic naltrexone treatment has not been extensively investigated in nonhuman subjects and aspects of its pharmacology remain uncertain. For example, the relative effectiveness of naltrexone in reducing the priming strength of opioid agonists differing in efficacy is not well understood. Here, using intravenous self-administration and warm-water tail withdrawal procedures, we investigated changes in the direct reinforcing effects of oxycodone and in the priming strength and antinociceptive effects of opioid agonists in squirrel monkeys (n = 4) during chronic treatment with naltrexone (0.2 mg/kg/d). Results show that naltrexone produced: 1) a 10-fold rightward shift in the dose-response function for the reinforcing effects of oxycodone, and 2) in reinstatement and antinociception experiments, comparable rightward shifts in the dose-response functions for higher-efficacy MOR agonists (methadone, heroin, and oxycodone) but rightward and downward shifts in the dose-response functions for lower-efficacy MOR agonists (buprenorphine, nalbuphine, and butorphanol). These results suggest that, although chronic naltrexone should be effective in forestalling relapse following exposure to lower- and higher-efficacy agonists, the inability of lower-efficacy agonists to surmount naltrexone antagonism may complicate the prescription of opioids for pain. SIGNIFICANCE STATEMENT: Although naltrexone is commonly used in the treatment of opioid use disorder, its ability to reduce the priming strength of opioid agonists has not been extensively investigated. This study shows that chronic naltrexone treatment induces rightward shifts in the reinstatement and antinociceptive properties of higher efficacy opioid agonists, but rightward and downward shifts for lower efficacy opioid agonists, suggesting lower efficacy agonists may not be able to surmount naltrexone-induced antagonism of these two effects, and perhaps naltrexone offers greater protection against lower efficacy agonists.

Design, synthesis and in vitro anticancer activity of some new lomefloxacin derivatives

Our main goal was to design and synthesize novel lomefloxacin derivatives that inhibit the topoisomerase II enzyme, leading to potent anticancer activity. Lomefloxacin derivatives substituted at position 3 and 7 were synthesized and screened for cytotoxic activity utilizing 60 different human cancer cell lines. Furthermore, compounds 3a,b,c,e that revealed potent broad-spectrum anticancer activity (with mean percent GI more than 47%) were further evaluated using five dose concentrations and calculating the GI50. Compound 3e was then evaluated for cell cycle analysis and demonstrated cell cycle arrest at the G2-M phase. Moreover, the mechanism of action was determined by determining the topoisomerase inhibitory activity and the molecular modeling study. Compounds 3a,b,c,e showed broad spectrum anticancer activity. Lomefloxacin derivative 5f showed selective cytotoxic activity against melanoma SK-MEL-5 cell line. Compound 3e demonstrated comparable topoisomerase II inhibition to doxorubicin with IC50 of 0.98 µM.

Exploring various measures of the area under the curve for the assessment of dose-proportionality and estimation of bioavailability

OBJECTIVE

In pharmacokinetics, the area under the concentration versus time curve (AUC) extrapolated to infinity (AUC0-∞) is the preferred metric but it is not always possible to have a reliable estimate of the terminal phase half-life. Here we sought to explore the accuracy of three different area measures to accurately identify dose proportionality and bioavailability.

METHODS

One to three compartment model simulations with different doses for dose-proportionality or different rates and/or extents of bioavailability. Area measures evaluated were AUC0-∞, to the last quantifiable concentration (AUCtlast), and to a common time value (AUCt').

RESULTS

Under linear pharmacokinetics, AUCt' provided the most accurate measure of dose proportionality. Except for the one compartment model where AUC0-∞ provided the best predictor of the true measure, there was no clear advantage to the use of either of the three measures of AUC.

CONCLUSION

With uncertainty about the terminal phase half-life, the use of AUCt' can be a very useful and even the preferred measure of exposure for use in assessing proportionality in exposure between doses. The choice of AUC measure in bioavailability is less clear and may depend on compartmental nature of the drug, and study parameters including assay sensitivity and sampling protocols.

An interactive tool for designing efficient toxicology experiments

The design of dose-response experiments is an important part of toxicology research. Efficient design of these experiments requires choosing optimal doses and assigning the correct number of subjects to those doses under a given criterion. Optimal design theory provides the tools to find the most efficient experimental designs in terms of cost and statistical efficiency. However, the mathematical details can be distracting and make these designs inaccessible to many toxicologists. To facilitate use of these designs, we present an easy to use web-app for finding two types of optimal designs for models commonly used in toxicology. We include tools for checking the optimality of a given design and for assessing efficiency of any user-supplied design. Using state-of-the-art nature-inspired metaheuristic algorithms, the web-app allows the user to quickly find optimal designs for estimating model parameters or the benchmark dose.

Safety, Tolerability, Pharmacokinetics, and Immunogenicity of the Anti-IFNAR1 Monoclonal Antibody QX006N: A First-in-Human Single Ascending Dose Study in Healthy Chinese Volunteers

BACKGROUND AND OBJECTIVE

QX006N is a novel, humanized, IgG4κ monoclonal antibody targeting IFNAR1, developed for the treatment of systemic lupus erythematosus. This study aims to investigate the pharmacokinetics, safety, tolerability, and immunogenicity of QX006N when administered intravenously to healthy Chinese individuals.

METHODS

A double-blind, randomized, placebo-controlled, single-ascending-dose, phase I clinical trial was conducted comprising five cohorts (n = 10 per cohort, except n = 5 for the first cohort). Subjects in each cohort were randomly assigned in a 4:1 ratio to receive a single intravenous infusion of QX006N (0.3 mg/kg, 1.0 mg/kg, 3.0 mg/kg, 6.0 mg/kg, or 10.0 mg/kg) or placebo for 30 minutes. Tolerability assessments included adverse events, vital signs, 12-lead electrocardiogram, physical examination, and clinical laboratory tests. The serum concentration of QX006N was measured using the enzyme-linked immunosorbent assay method, and the anti-drug antibodies were detected using the electrochemiluminescence assay method.

RESULTS

QX006N demonstrated a favorable safety and tolerability profile throughout the study. All treatment-emergent adverse events were of Grade 1-2 (CTCAE Version 5.0), and no serious adverse events, deaths, or drug discontinuations because of treatment-emergent adverse events were observed. All drug-related treatment-emergent adverse events showed no clear dose-related trends. Following an intravenous infusion of QX006N at doses that ranged from 0.3 mg/kg to 10 mg/kg, the half-life increased from 24.7 to 208 hours in a dose-dependent manner, while clearance decreased from 0.0828 to 0.0065 L/h. The maximum concentration exhibited nearly dose-proportional increases, and the area under the curve displayed a more than dose-proportional increment with non-linear pharmacokinetic characteristics. The incidence of anti-drug antibodies was observed to increase over time for doses that ranged from 1.0 mg/kg to 10.0 mg/kg of QX006N, reaching its peak at day 57 (range 62.50-87.50%). Conversely, the incidence of anti-drug antibodies in the QX006N 0.3-mg/kg and placebo cohorts remained low.

CONCLUSIONS

QX006N demonstrated acceptable safety, tolerability, and pharmacokinetic characteristics in healthy subjects when administered as a single intravenous infusion at doses that ranged from 0.3 mg/kg to 10.0 mg/kg. Based on the pharmacokinetic and safety outcomes, a recommended effective dose of 300 mg is proposed for future phase Ib studies.

CLINICAL TRIAL REGISTRATION

This study has been registered at http://www.chinadrugtrials.org.cn/ under identifier CTR20212834.

Virtual clinical QT exposure-response studies - A translational computational approach

BACKGROUND AND PURPOSE

A recent paradigm shift in proarrhythmic risk assessment suggests that the integration of clinical, non-clinical, and computational evidence can be used to reach a comprehensive understanding of the proarrhythmic potential of drug candidates. While current computational methodologies focus on predicting the incidence of proarrhythmic events after drug administration, the objective of this study is to predict concentration-response relationships of QTc as a clinical endpoint.

EXPERIMENTAL APPROACH

Full heart computational models reproducing human cardiac populations were created to predict the concentration-response relationship of changes in the QT interval as recommended for clinical trials. The concentration-response relationship of the QT-interval prolongation obtained from the computational cardiac population was compared against the relationship from clinical trial data for a set of well-characterized compounds: moxifloxacin, dofetilide, verapamil, and ondansetron.

KEY RESULTS

Computationally derived concentration-response relationships of QT interval changes for three of the four drugs had slopes within the confidence interval of clinical trials (dofetilide, moxifloxacin and verapamil) when compared to placebo-corrected concentration-ΔQT and concentration-ΔQT regressions. Moxifloxacin showed a higher intercept, outside the confidence interval of the clinical data, demonstrating that in this example, the standard linear regression does not appropriately capture the concentration-response results at very low concentrations. The concentrations corresponding to a mean QTc prolongation of 10 ms were consistently lower in the computational model than in clinical data. The critical concentration varied within an approximate ratio of 0.5 (moxifloxacin and ondansetron) and 1 times (dofetilide, verapamil) the critical concentration observed in human clinical trials. Notably, no other in silico methodology can approximate the human critical concentration values for a QT interval prolongation of 10 ms.

CONCLUSION AND IMPLICATIONS

Computational concentration-response modelling of a virtual population of high-resolution, 3-dimensional cardiac models can provide comparable information to clinical data and could be used to complement pre-clinical and clinical safety packages. It provides access to an unlimited exposure range to support trial design and can improve the understanding of pre-clinical-clinical translation.

Mifepristone decreases nicotine intake in dependent and non-dependent adult rats

BACKGROUND

Addiction to tobacco and nicotine products has adverse health effects and afflicts more than a billion people worldwide. Therefore, there is an urgent need for new treatments to reduce tobacco and nicotine use. Glucocorticoid receptor blockade shows promise as a novel treatment for drug abuse and stress-related disorders.

AIM

These studies aim to investigate whether glucocorticoid receptor blockade with mifepristone diminishes the reinforcing properties of nicotine in rats with intermittent or daily long access to nicotine.

METHODS

The rats self-administered 0.06 mg/kg/inf of nicotine for 6 h per day, with either intermittent or daily access for 4 weeks before treatment with mifepristone. Daily nicotine self-administration models regular smoking, while intermittent nicotine self-administration models occasional smoking. To determine whether the rats were dependent, they were treated with the nicotinic acetylcholine receptor antagonist mecamylamine, and somatic signs were recorded.

RESULTS

The rats with intermittent access to nicotine had a higher level of nicotine intake per session than those with daily access but only the rats with daily access to nicotine showed signs of physical dependence. Furthermore, mecamylamine increased nicotine intake during the first hour of access in rats with daily access but not in those with intermittent access. Mifepristone decreased total nicotine intake in rats with intermittent and daily access to nicotine. Moreover, mifepristone decreased the distance traveled and rearing in the open field test and operant responding for food pellets.

CONCLUSION

These findings indicate that mifepristone decreases nicotine intake but this effect may be partially attributed to the sedative effects of mifepristone.

Advanced Model-based Approach to Evaluate Human Plasma, Cerebrospinal Fluid, and Neuronal mTORC1 Activation Biomarkers After NV-5138 Administration in Healthy Volunteers

PURPOSE

NV-5138 ([S]-2-amino-5,5-difluoro-4,4-dimethylpentanoic acid) is an orally bioavailable, small-molecule activator of the mechanistic target of rapamycin complex 1 (mTORC1) pathway in development for treatment-resistant depression. The authors established a model to describe the relationship between plasma and cerebrospinal fluid (CSF) concentrations of NV-5138 and between CSF concentrations and potential biomarkers thought to be associated with mTORC1 activity (ie, orotic acid, N-acetylmethionine, and N-formylmethionine).

METHODS

Data were collected from a randomized, double-blind, placebo-controlled, tolerability, and pharmacokinetic (PK) parameter study of 5 ascending (400, 800, 1600, 2400, and 3000 mg), once-daily oral doses of NV-5138 in healthy subjects. NV-5138 plasma PK parameter samples were collected at 15 time points over 24 hours on days 1 and 7, and at pre dose on days 2-6 for all doses. NV-5138 CSF PK parameter and CSF biomarker samples were collected on days 1 and 7 at pre dose and 4, 8, and 12 hours post dose for all doses except 3000 mg. A model-based approach was used to develop and validate a model that describes the relationship between NV-5138 in CSF and biomarker concentrations.

FINDINGS

Twenty-four of the 42 enrolled subjects had simultaneous plasma and CSF measurements of NV-5138 and CSF biomarker concentrations and were included in the PK parameter and pharmacodynamic (PD) analyses. A 2-compartment plasma and CSF PK parameter, with indirect PD effects, model was developed and validated. NV-5138 plasma concentrations were positively correlated with those in CSF, although CSF concentrations lagged slightly behind those in plasma, as indicated by a counterclockwise hysteresis effect. Similarly, the relationship between the PD measures of mTORC1 activation and NV-5138 was also characterized by counterclockwise hysteresis, when the increase in CSF biomarker concentrations lagged behind those of NV-5138, consistent with a signaling intermediary/cascade, such as mTORC1. Maximal biomarker activation was achieved at NV-5138 CSF concentrations of approximately 3 µg/mL, which were associated with daily doses of 1600 mg NV-5138. The safety profile analysis (n = 42) found that most of the reported adverse events were mild in severity, with no severe, serious, unusual, or unexpected adverse events or any dissociative effects; 2 subjects (400-mg cohort) discontinued due to adverse events that were judged to be unrelated to study medication.

IMPLICATIONS

The model will be used for designing future efficacy and tolerability studies. Consecutive daily doses of NV-5138 were well tolerated in this healthy volunteer study.

Dose-finding based on feasibility and late-onset toxicity in adoptive cell therapy trials

Cell therapies comprise one of the most important advances in oncology. One of the biggest challenges in the early development of cell therapies is to recommend safe and feasible doses to carry forward to middle development. The treatment involves extracting cells from a patient, expanding the cells and infusing the cells back into the patient. Each dose level being studied is defined by the number of cells infused into the trial participant. The manufacturing process may not generate enough cells for a given patient to receive their assigned dose level, making it infeasible to administer their intended dose. The primary design challenge is to efficiently use accumulated data from participants treated away from their assigned dose to efficiently allocate future trial participants and recommend a feasible maximum tolerated dose (FMTD) at the study conclusion. Currently, there are few available options for designing and implementing Phase I trials of cell therapies that can incorporate a dose feasibility endpoint. Moreover, the application of these designs is limited to a traditional dose-finding framework, where the dose-limiting toxicity (DLT) endpoint is observed in early cycles of therapy. This paper presents a novel phase I trial design for adoptive cell therapy that simultaneously accounts for dose feasibility and late-onset toxicities. We apply our design to a phase I dose-escalation trial of Rituximab-based bispecific activated T-cells combined with a fixed dose of Nivolumab. Our simulation results demonstrate that our proposed method can reduce trial duration without significantly hindering trial accuracy.

Pharmacokinetics, Safety Profile, and Tolerability of Tetramethylpyrazine Nitrone Tablets After Single and Multiple Ascending Doses in Healthy Chinese Volunteers

BACKGROUND AND OBJECTIVES

Tetramethylpyrazine nitrone (TBN) is a novel tetramethylpyrazine derivative armed with a strong free radical scavenging nitrone moiety. This study aims to evaluate the pharmacokinetics, safety profile, and tolerability of TBN tablets after a single ascending dose (SAD) and multiple ascending doses (MAD) in healthy Chinese volunteers.

METHODS

This phase I, single-center, open-label study was conducted in China. The SAD portion consisted of four cohorts with dose levels of 400-1800 mg. The MAD portion included three cohorts in which subjects received doses of 600-1800 mg twice daily for 7 days (13 consecutive doses). The third portion was a randomized, two-period, crossover design to assess the influence of food with a single dose of TBN tablets (1200 mg). The safety profile was evaluated by monitoring adverse events (AEs), vital signs, electrocardiograms, physical examinations, and laboratory test results.

RESULTS

Fifty-two healthy subjects aged 18 to 45 years with a body mass index between 19.0 and 26.0 kg/m2 were enrolled. After a single dose of TBN, the median time to maximum plasma concentration (Tmax) was 2.48-3.24 h and the mean half-life (t1/2) was 1.28 to 2.10 h across all doses. In the MAD study, the median Tmax was 2.48 to 3.48 h. In the 400-1800 mg dose range, there was a tendency for less than proportional increases in the maximum plasma concentration (Cmax), the area under the concentration-time curve from 0 to time of last measurable concentration (AUC0-t), and the area under the concentration-time curve from 0 to infinity (AUC0-inf) in both single- and multiple-dose periods. A significantly higher TBN exposure was observed in females than males in both a single and multiple doses of the 600 mg and 1200 mg groups, with a geometric mean female-to-male ratio of 138.69-203.18%. Food decreased the Cmax and AUC0-t of TBN to 45.19% and 59.73%, respectively. Each dose group reached a steady state after 4 days. No drug accumulation was observed. Two subjects had drug-related AEs. A decreased neutrophil count and drug eruption in the SAD portion (1200 mg group) and an increased alanine aminotransferase level in the food effect group were found. All AEs were mild and tolerable (CTCAE grade 1) and resolved without any medical intervention.

CONCLUSION

TBN tablets had a good safety profile and were well tolerated in healthy Chinese volunteers. Steady-state concentrations were reached after 4 consecutive days of oral administration. The results of this phase I study will provide guidance for the design of future TBN clinical studies.

CHINESE CLINICAL TRIAL REGISTRY

ChiCTR1900022092.

Safety, pharmacokinetics and pharmacodynamics of HRS-7535, a novel oral small molecule glucagon-like peptide-1 receptor agonist, in healthy participants: A phase 1, randomized, double-blind, placebo-controlled, single- and multiple-ascending dose, and food effect trial

AIM

To assess the safety, tolerability, pharmacokinetics (PKs) and pharmacodynamics of HRS-7535, a novel glucagon-like peptide-1 receptor agonist (GLP-1RA), in healthy participants.

MATERIALS AND METHODS

This phase 1 trial consisted of single-ascending dose (SAD), food effect (FE) and multiple-ascending dose (MAD) parts. In the SAD part, participants were randomized (6:2) to receive HRS-7535 (at doses of 15, 60 and 120 mg; administered orally once daily) or placebo. In the FE part, participants were randomized (8:2) to receive a single dose of 90-mg HRS-7535 or placebo, in both fed and fasted states. In the MAD part, participants were randomized (18:6) to receive daily HRS-7535 (120 mg [30/60/90/120-mg titration scheme]) or placebo for 28 days. The primary endpoints were safety and tolerability.

RESULTS

Nausea and vomiting were the most frequently reported AEs across all three parts. In the SAD part, the median Tmax was 5.98-5.99 hours and the geometric mean t1/2 was 5.28-9.08 hours across the HRS-7535 dosing range. In the MAD part, the median Tmax was 5.98-10.98 hours and the geometric mean t1/2 was 6.48-8.42 hours on day 28 in participants on HRS-7535. PKs were approximately dose-proportional. On day 29 in the MAD part, the mean (percentage) reduction in body weight from baseline was 4.38 kg (6.63%) for participants who received HRS-7535, compared with 0.8 kg (1.18%) for those participants who received a placebo.

CONCLUSIONS

HRS-7535 exhibited a safety and tolerability profile consistent with other GLP-1RAs and showed PKs suitable for once-daily dosing. These findings support further clinical development of HRS-7535 for type 2 diabetes.

Guanfacine for the Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents with Down Syndrome: A Retrospective Chart Review

Study Design: Retrospective case series. Objectives: The objective of this study was to provide naturalistic data on the use of guanfacine for the treatment of attention-deficit/hyperactivity disorder (ADHD) in a clinically referred sample of youth with Down syndrome (DS). Methods: The medical records of children and adolescents with DS who received guanfacine for the treatment of ADHD from a multidisciplinary neurodevelopmental disorder clinic between September 1, 2011, and September 10, 2021, were reviewed. Demographic and clinical characteristics, guanfacine dose and treatment duration, and adverse effects were recorded. Clinical Global Impression Scale (CGI) scores for ADHD symptom severity (S) and improvement (I) were retrospectively assigned by a child and adolescent psychiatrist based on review of the clinic notes. Response to guanfacine was defined as completion of at least 12 weeks of treatment and a Clinical Global Impression Improvement subscale rating ≤2 (1 = "very much improved" or 2 = "much improved"). Results: Twenty-one patients were eligible for inclusion, of whom 17 (81%) completed at least 12 weeks of guanfacine. Ten of the 21 patients (48%; 95% confidence interval [CI]: 28%-68%) responded to treatment. The median time on guanfacine treatment covered by the clinic notes was 50.4 weeks, with a range of 0.3 weeks to 7.5 years. Thirteen patients (62%) remained on guanfacine at the time of their most recent clinic note. Nine patients had adverse events documented in their clinic notes (43%; 95% CI: 24%-63%), most commonly sleepiness (n = 7) and constipation (n = 2). Conclusion: About half of patients with DS responded to guanfacine for the treatment of ADHD and many tolerated long-term use. Study limitations primarily relate to the retrospective nature of the study and small sample size.

Efficacy and tolerability of adjunctive lacosamide in patients aged <4 years with focal seizures

OBJECTIVE

Primary objective was to evaluate efficacy of lacosamide administered concomitantly with 1-3 antiseizure medications in young children with uncontrolled focal (partial-onset) seizures.

METHODS

Double-blind, parallel-group trial (SP0967: NCT02477839/2013-000717-20) conducted between June 2015 and May 2020 at hospitals and clinics in 25 countries. Patients (aged ≥1 month to <4 years) with uncontrolled focal seizures were randomized 1:1 to adjunctive lacosamide or placebo using an interactive voice/web response system and stratified by age. After a 20-day titration period, patients who reached target-dose range (8-12 mg/kg/day) entered a 7-day maintenance period. Region-specific primary efficacy variables were based on ≤72-h video-electroencephalograms: change in average daily frequency (ADF) of electrographic focal seizures as measured on end-of-maintenance video-electroencephalogram versus end-of-baseline video-electroencephalogram (United States); 50% responder rate (≥50% reduction in ADF of focal seizures) during maintenance (European Union).

RESULTS

In total, 255 patients were randomized (lacosamide/placebo: 128/127) and received ≥1 trial medication dose. Percentage reduction in ADF of focal seizures for lacosamide (116 patients) versus placebo (120 patients) was 3.2% (95% confidence interval = -13.6 to 17.5, p = 0.69). 50% responder rate was 41.4% for lacosamide (116 patients), 37.5% for placebo (120 patients) (p = 0.58). Treatment-emergent adverse events were reported by 44.5% of lacosamide-treated patients (placebo 51.2%).

INTERPRETATION

Adjunctive lacosamide did not show superior efficacy versus placebo in young children with focal seizures. However, efficacy variables were potentially affected by high variability and low reliability between readers in video-electroencephalogram interpretation. Lacosamide was generally well tolerated; safety profile was acceptable and consistent with that in adults and children aged ≥4 years.

Safety and Pharmacokinetics of HRS-2261, a P2X3 Receptor Antagonist, in Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled Phase 1 Study

BACKGROUND

P2X3 receptor antagonists hold promising potential as a therapeutic option for patients with refractory or unexplained chronic cough, a condition lacking approved therapies. This study assessed the safety, tolerability, and pharmacokinetics (PK) of HRS-2261, a novel selective P2X3 receptor antagonist, in healthy subjects.

METHODS

This randomized, double-blinded, placebo-controlled phase 1 trial of HRS-2261 consisted of three phases: the single ascending dose (SAD) study phase, the food-effect study phase, and the multiple ascending dose (MAD) study phase. In the SAD phase, healthy subjects were randomly assigned to receive a single oral dose of HRS-2261 (25, 100, 200, 400, 800, and 1200 mg) or placebo. Subjects in the 200 mg group of the SAD phase progressed directly to the food-effect phase following safety evaluation. In the MAD phase, healthy subjects were randomized to receive HRS-2261 (50, 200, and 400 mg) or placebo twice daily for 14 consecutive days. The primary endpoints were safety and tolerability.

RESULTS

A total of 62 and 30 subjects were enrolled in the SAD and MAD phases, respectively, with 12 subjects from the SAD phase transitioning to the food-effect phase. The incidence and severity of adverse events (AEs) were not dose dependent, and most AEs were mild except for one moderate AE (epididymitis, which was not related to treatment) in the 400 mg group. Dysgeusia was reported in nine subjects, including two from the SAD phase, one from the food-effect phase, and six from the MAD phase. The median Tmax and geometric mean t1/2 were 0.9-2.0 h and 4.1-8.5 h in the SAD, and 2.0-2.7 h and 4.6-5.0 h on day 14 in the MAD, respectively. Drug exposures in the SAD and MAD phases were both less than dose proportional. The accumulation of the drug was slight with repeated twice-daily dosing. Food-effect study results showed that food intake did not affect the plasma exposure of HRS-2261.

CONCLUSIONS

HRS-2261 demonstrated good tolerability, with a low incidence of dysgeusia. The PK profile was favorable. This study supports further development of HRS-2261 as a potential P2X3 receptor antagonist for chronic cough.

TRIAL REGISTRATION NUMBER

Clinical trials.gov, identifier: NCT05274516. Trial registration date: March 10, 2022.

The imidazoline I2 receptor agonist 2-BFI reduces abuse-related effects of morphine: self-administration and drug discrimination

RATIONALE

Increasing evidence shows that imidazoline I2 receptor agonists enhance opioid-induced analgesia, suggesting that the combination of I2 receptor agonists with opioids could be a favorable strategy for pain control. However, the effect of I2 receptor agonists on the abuse liability of opioids is unknown. This study examined the impact of the I2 receptor agonist 2-BFI on some abuse-related behavioral effects of the opioid morphine in rats.

OBJECTIVES

The von Frey filament test was used to determine the antinociceptive effects of 2-BFI (intravenous, i.v.) in a rat model of complete Freund's adjuvant (CFA)-induced inflammatory pain. IV self-administration was used to assess the reinforcing effects of 2-BFI alone and to assess the effects of non-contingent injections of 2-BFI (i.p.) on morphine self-administration. A two-lever drug discrimination paradigm in which rats were trained to discriminate 3.2 mg/kg morphine (i.p.) from saline was used to examine whether 2-BFI or another I2 receptor agonist 2-(4,5-dihydroimidazol-2-yl)quinoline hydrochloride (BU224) affected the discriminative stimulus effects of morphine.

RESULTS

2-BFI could not maintain reliable self-administration behavior in rats with no pain or CFA-treated inflammatory pain. However, pretreatment with 2-BFI (i.p.) produced dose-dependent decreases in the dose-effect curve of morphine self-administration. Both 2-BFI and BU224 did not substitute for morphine but significantly attenuated the discriminative stimulus effects of morphine.

CONCLUSIONS

These results suggest that I2 receptor agonists do not enhance, but in fact appear to decrease, the abuse liability of opioids, further supporting the potential utility of I2 receptor agonist-opioid combination therapy for pain control.

Safety, Tolerability, and Pharmacokinetics of a Novel Macrocyclic Gadolinium-Based Contrast Agent, HNP-2006, in Healthy Subjects

OBJECTIVES

Gadolinium-based contrast agents (GBCAs) are indispensable in contrast-enhanced magnetic resonance imaging. A higher risk of gadolinium deposition in linear GBCAs required the introduction of macrocyclic GBCAs with a stable molecular structure. We conducted the first-in-human study to evaluate the safety, tolerability, and pharmacokinetics (PKs) of HNP-2006, a novel macrocyclic GBCA, in healthy male subjects.

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind, single-ascending dose study was conducted. Subjects received either a single intravenous bolus injection of HNP-2006 or its matching placebo with a treatment-to-placebo ratio of 6:2 at the dose level of 0.02, 0.05, 0.1, 0.2, and 0.3 mmol/kg. Safety was assessed through routine clinical assessments. Blood sampling and urine collection were performed up to 72 hours postdose for PK assessments. Noncompartmental methods were used to calculate PK parameters, and a population PK model was constructed.

RESULTS

Overall, 40 subjects completed the study. Fourteen subjects reported 22 treatment-emergent adverse events (TEAEs). The severity of all TEAEs was mild, and the HNP-2006 dose was associated with the incidence of TEAEs. The most common TEAEs included nausea and dizziness, which occurred within an hour of administration. HNP-2006 was rapidly eliminated by urinary excretion with a half-life of 1.8-2.0 hours and showed a dose-proportional PK. A 2-compartment model had the best fit with the population PK analysis.

CONCLUSIONS

A single intravenous dose of HNP-2006 was well-tolerated and safe up to 0.30 mmol/kg. HNP-2006 was rapidly excreted in urine and exhibited dose-independent PK profiles.

An extended Bayesian semi-mechanistic dose-finding design for phase I oncology trials using pharmacokinetic and pharmacodynamic information

We propose a model-based, semi-mechanistic dose-finding (SDF) design for phase I oncology trials that incorporates pharmacokinetic/pharmacodynamic (PK/PD) information when modeling the dose-toxicity relationship. This design is motivated by a phase Ib/II clinical trial of anti-CD20/CD3 T cell therapy in non-Hodgkin lymphoma patients; it extends a recently proposed SDF model framework by incorporating measurements of a PD biomarker relevant to the primary dose-limiting toxicity (DLT). We propose joint Bayesian modeling of the PK, PD, and DLT outcomes. Our extensive simulation studies show that on average the proposed design outperforms some common phase I trial designs, including modified toxicity probability interval (mTPI) and Bayesian optimal interval (BOIN) designs, the continual reassessment method (CRM), as well as an SDF design assuming a latent PD biomarker (SDF-woPD), in terms of the percentage of correct selection of maximum tolerated dose (MTD) and average number of patients allocated to MTD, under a variety of dose-toxicity scenarios. When the working PK model and the class of link function between the cumulative PD effect and DLT probability is correctly specified, the proposed design also yields better estimated dose-toxicity curves than CRM and SDF-woPD. Our sensitivity analyses suggest that the design's performance is reasonably robust to prior specification for the parameter in the link function, as well as misspecification of the PK model and class of the link function.

Backfilling Patients in Phase I Dose-Escalation Trials Using Bayesian Optimal Interval Design (BOIN)

In recent years, there has been increased interest in incorporation of backfilling into dose-escalation clinical trials, which involves concurrently assigning patients to doses that have been previously cleared for safety by the dose-escalation design. Backfilling generates additional information on safety, tolerability, and preliminary activity on a range of doses below the maximum tolerated dose (MTD), which is relevant for selection of the recommended phase II dose and dose optimization. However, in practice, backfilling may not be rigorously defined in trial protocols and implemented consistently. Furthermore, backfilling designs require careful planning to minimize the probability of treating additional patients with potentially inactive agents (and/or subtherapeutic doses). In this paper, we propose a simple and principled approach to incorporate backfilling into the Bayesian optimal interval design (BOIN). The design integrates data from the dose-escalation and backfilling components of the design and ensures that the additional patients are treated at doses where some activity has been seen. Simulation studies demonstrated that the proposed backfilling BOIN design (BF-BOIN) generates additional data for future dose optimization, maintains the accuracy of the MTD identification, and improves patient safety without prolonging the trial duration.

Synthesis and Antitumor Activity Evaluation of Novel Echinatin Derivatives with a 1,3,4-Oxadiazole Moiety

A series of novel echinatin derivatives with 1,3,4-oxadiazole moieties were designed and synthesized. Most of the newly synthesized compounds exhibited moderate antiproliferative activity against the four cancer cell lines. Notably, Compound T4 demonstrated the most potent activity, with IC50 values ranging from 1.71 µM to 8.60 µM against the four cancer cell lines. Cell colony formation and wound healing assays demonstrated that T4 significantly inhibited cell proliferation and inhibited migration. We discovered that T4 exhibited moderate binding affinity with the c-KIT protein through reverse docking. The results were effectively validated through subsequent molecular docking and c-KIT enzyme activity assays. In addition, Western blot analysis revealed that T4 inhibits the phosphorylation of downstream proteins of c-KIT. The results provide valuable inspiration for exploring novel insights into the design of echinatin-related hybrids as well as their potential application as c-KIT inhibitors to enhance the efficacy of candidates.

A new function for drug combination dose finding trials

Combination drugs play an essential role in treating cancers. The challenging part of the combination drugs are to specify the dose-toxicity ordering, which means the sequences of dose escalation and de-escalation in process of dose findings should be pre-determined. In the paper, we extend a novel function of the continual reassessment method based on the combination of the normal distribution for drug-combination dose-finding trials and systematically evaluate its performance using a template of four performance measures EARS (Efficiency, Accuracy, Reliability, Selection). Dose escalation and deescalation rules are based on the nearest neighborhood continual reassessment method for a combination drug, and we specify all possible dose-toxicity orderings in the trial. Simulation demonstrates that the new design is efficient, accurate and reasonably reliable.

An Oral Interleukin-23-Receptor Antagonist Peptide for Plaque Psoriasis

BACKGROUND

The use of monoclonal antibodies has changed the treatment of several immune-mediated inflammatory diseases, including psoriasis. However, these large proteins must be administered by injection. JNJ-77242113 is a novel, orally administered interleukin-23-receptor antagonist peptide that selectively blocks interleukin-23 signaling and downstream cytokine production.

METHODS

In this phase 2 dose-finding trial, we randomly assigned patients with moderate-to-severe plaque psoriasis to receive JNJ-77242113 at a dose of 25 mg once daily, 25 mg twice daily, 50 mg once daily, 100 mg once daily, or 100 mg twice daily or placebo for 16 weeks. The primary end point was a reduction from baseline of at least 75% in the Psoriasis Area and Severity Index (PASI) score (PASI 75 response; PASI scores range from 0 to 72, with higher scores indicating greater extent or severity of psoriasis) at week 16.

RESULTS

A total of 255 patients underwent randomization. The mean PASI score at baseline was 19.1. The mean duration of psoriasis was 18.2 years, and 78% of the patients across all the trial groups had previously received systemic treatments. At week 16, the percentages of patients with a PASI 75 response were higher among those in the JNJ-77242113 groups (37%, 51%, 58%, 65%, and 79% in the 25-mg once-daily, 25-mg twice-daily, 50-mg once-daily, 100-mg once-daily, and 100-mg twice-daily groups, respectively) than among those in the placebo group (9%), a finding that showed a significant dose-response relationship (P<0.001). The most common adverse events included coronavirus disease 2019 (in 12% of the patients in the placebo group and in 11% of those across the JNJ-77242113 dose groups) and nasopharyngitis (in 5% and 7%, respectively). The percentages of patients who had at least one adverse event were similar in the combined JNJ-77242113 dose group (52%) and the placebo group (51%). There was no evidence of a dose-related increase in adverse events across the JNJ-77242113 dose groups.

CONCLUSIONS

After 16 weeks of once- or twice-daily oral administration, treatment with the interleukin-23-receptor antagonist peptide JNJ-77242113 showed greater efficacy than placebo in patients with moderate-to-severe plaque psoriasis. (Funded by Janssen Research and Development; FRONTIER 1 ClinicalTrials.gov number, NCT05223868.).

A Phase 3, Randomized, Controlled Trial of Resmetirom in NASH with Liver Fibrosis

BACKGROUND

Nonalcoholic steatohepatitis (NASH) is a progressive liver disease with no approved treatment. Resmetirom is an oral, liver-directed, thyroid hormone receptor beta-selective agonist in development for the treatment of NASH with liver fibrosis.

METHODS

We are conducting an ongoing phase 3 trial involving adults with biopsy-confirmed NASH and a fibrosis stage of F1B, F2, or F3 (stages range from F0 [no fibrosis] to F4 [cirrhosis]). Patients were randomly assigned in a 1:1:1 ratio to receive once-daily resmetirom at a dose of 80 mg or 100 mg or placebo. The two primary end points at week 52 were NASH resolution (including a reduction in the nonalcoholic fatty liver disease [NAFLD] activity score by ≥2 points; scores range from 0 to 8, with higher scores indicating more severe disease) with no worsening of fibrosis, and an improvement (reduction) in fibrosis by at least one stage with no worsening of the NAFLD activity score.

RESULTS

Overall, 966 patients formed the primary analysis population (322 in the 80-mg resmetirom group, 323 in the 100-mg resmetirom group, and 321 in the placebo group). NASH resolution with no worsening of fibrosis was achieved in 25.9% of the patients in the 80-mg resmetirom group and 29.9% of those in the 100-mg resmetirom group, as compared with 9.7% of those in the placebo group (P<0.001 for both comparisons with placebo). Fibrosis improvement by at least one stage with no worsening of the NAFLD activity score was achieved in 24.2% of the patients in the 80-mg resmetirom group and 25.9% of those in the 100-mg resmetirom group, as compared with 14.2% of those in the placebo group (P<0.001 for both comparisons with placebo). The change in low-density lipoprotein cholesterol levels from baseline to week 24 was -13.6% in the 80-mg resmetirom group and -16.3% in the 100-mg resmetirom group, as compared with 0.1% in the placebo group (P<0.001 for both comparisons with placebo). Diarrhea and nausea were more frequent with resmetirom than with placebo. The incidence of serious adverse events was similar across trial groups: 10.9% in the 80-mg resmetirom group, 12.7% in the 100-mg resmetirom group, and 11.5% in the placebo group.

CONCLUSIONS

Both the 80-mg dose and the 100-mg dose of resmetirom were superior to placebo with respect to NASH resolution and improvement in liver fibrosis by at least one stage. (Funded by Madrigal Pharmaceuticals; MAESTRO-NASH ClinicalTrials.gov number, NCT03900429.).

N-phenyl and N-benzyl substituted succinimides: Preclinical evaluation for their antihypertensive effect and underlying mechanism

The study was designed to investigate the antihypertensive potential of 2-(2, 5-dioxo-1-phenylpyrrolidin-3-yl)-3-(4-isopropylphenyl)-2-methylpropanal (Comp-1) and 2-(1-benzyl-2,5-dioxopyrrolidin-3-yl)-3-(4-isopropylphenyl)-2-methylpropanal (Succ-5) in rats. The study results showed that, just like nifedipine (the standard reference drug), the test compounds, Comp-1 (at doses of 15 and 20 mg/kg) and Succ-5 (at a dose of 20 mg/kg) had significant antihypertensive effect against deoxycorticosterone acetate-salted rats. The test compounds maintained the level of cardiac markers troponin I and creatinine kinase myocardial bands (CK-MB) in serum, and modulate the oxidative stress markers Glutathione s-transferase (GST) activity, reduced glutathione (GSH), catalase levels, and lipid peroxidation (LPO). These compounds also reduced the expression of inflammatory markers, including cyclooxygenase-2 (COX-2) and tumor necrosis factor alpha (TNF-α) in heart tissues. Furthermore, in the ex-vivo study, the test substances relaxed the contractions induced by phenylephrine (PE) and potassium (K+). Vasodilation was endothelium-independent because the test substances showed nearly the same effect in aortic rings with intact endothelium, denuded endothelium, and with L-NAME pretreatment. The test compounds shifted the calcium curve to the right, i.e., contraction was inhibited and decreased the maximal response. This study demonstrated the antihypertensive, anti-inflammatory, antioxidant, and vasodilate effects of the test compounds. In addition, the results supported the phenomenon of calcium channel blockades responsible for vasodilation.

Pharmacokinetic and safety profiles of mesalazine enema in healthy Chinese subjects: A single- and multiple-dose study

Mesalazine is a well-established treatment for ulcerative colitis by oral or topical administration. However, the pharmacokinetic (PK) and safety profiles of mesalazine administered by an enema has not been clarified in Chinese population. We conducted an open-label study to assess the PK and safety profiles of mesalazine in 11 healthy Chinese subjects after receiving mesalazine enema (1 g/100 mL) once daily for 7 consecutive days. Blood and urine samples were collected for assay of mesalazine and N-acetyl mesalazine by liquid chromatography-tandem mass spectrometry. The PK and safety data were summarized using descriptive statistics. The mean (standard deviation) maximum plasma concentration (Cmax), area under plasma drug concentration-time curve from time 0 to the last measurable plasma concentration time point (AUC0-t) and elimination half-life (t1/2) of mesalazine were 1007.64 (369.00) ng/mL, 9608.59 (3533.08) h·ng/mL and 3.33 (1.99) h, respectively after the first dose administration. In multiple-dose study, the estimated accumulation factor of mesalazine was 1.09. The cumulative urinary excretion rate of parent and major metabolite of mesalazine was 27.77%. After the last doe administration, 2.21% of the administered dose was excreted as mesalazine and 24.47% as N-acetyl mesalazine in urine within 24 h. Overall, 9 adverse events (AEs) were reported in 4 of the 11 subjects (36.4%), including oral ulcer, toothache, upper respiratory tract infection (1 each) and laboratory abnormalities (6 cases). All AEs were mild and recovered spontaneously without treatment, and were not considered as related to mesalazine. Mesalazine enema (1 g/100 mL) was safe and well tolerated in healthy Chinese subjects. These findings support further clinical trials in Chinese patients. Trial registration: This trial was registered to Chinese Clinical Trial Registry (ChiCTR) at https://www.chictr.org.cn (registration number: ChiCTR2300073148).

A model-informed approach to accelerate the clinical development of cofrogliptin (HSK7653), a novel ultralong-acting dipeptidyl peptidase-4 inhibitor

AIM

To employ a model-informed drug development approach in facilitating decision making and expediting the clinical progress of cofrogliptin (HSK7653), a novel ultralong-acting dipeptidyl peptidase-4 (DPP-4) inhibitor, for the treatment of type 2 diabetes (T2D) via a biweekly dosing regimen.

METHODS

Firstly, a population pharmacokinetics and pharmacodynamics (PopPKPD) model was developed using PK and PD data from a single ascending dose study to simulate the PK and PD time profiles of HSK7653 after multiple doses. Secondly, model-based meta-analysis (MBMA) was performed on published clinical studies of Eastern Asian subjects for all DPP-4 inhibitors. We hypothesized a consistent relationship between PK and DPP-4 inhibition in both healthy individuals and in those with T2D, establishing a quantitative correlation between DPP-4 inhibition and HbA1c. Finally, the predicted PK/DPP-4 inhibition/HbA1c profiles were validated by T2D patients in late clinical trials.

RESULTS

The PK/DPP-4 inhibition/HbA1c profiles of T2D patients treated with HSK7653 matched the modelled data. Our PopPKPD and MBMA models predict multiple ascending dosing PK and PD characteristics from single ascending dosing data, as well as the long-term efficacy in T2D patients, based on healthy subjects.

CONCLUSIONS

Successful waiver approval for the phase 2b dose-finding study was achieved through model-informed recommendations, facilitating the clinical development of HSK7653 and other DPP-4 inhibitors.

DDT exposure induces tremor-like behavior and neurotoxicity in developmental stages of embryonic zebrafish

Dichlorodiphenyltrichloroethane (DDT) is a broad-spectrum insecticide, widely detected in environments due to its high stability characteristic and long natural half-life period. The adverse impact of DDT exposure on organisms and humans has attracted great concern worldwide. The current study explored the developmental and neurobehavioral toxicity response of DDT in embryonic zebrafish. The embryos were treated with DDT (0, 0.1, 1, 2.5 and 5 µM) during 6 h post fertilization (hpf) to 144 hpf. Our result indicated that DDT exposures increased the embryo hatching rate at 48 and 60 hpf, the larval malformation rate at 120 hpf and mortality rate at 144 hpf. The manifested malformations included uninflated swim bladder, bent spine and tail, deformed liver, and pericardial edema. The 120 hpf larval organs size of the gut and swim bladder was decreased in higher exposed concentration groups. Besides, DDT exposure resulted in hyperactivity for the embryo spontaneous movement at 24 hpf and tremor like movement measured by the free larval activity at 72 hpf, as well as the larval activity at 96 hpf under light-dark transition stimulus. Mechanistic examinations at 120 hpf revealed DDT exposure elevated oxidative stress through MDA formation increase, ATP level decrease as well as antioxidant enzyme genes (sod1 and gpx1a) expression decrease. DDT exposure induced abnormal neurotransmitters expression with DA level increase, 5-HT and NOS level decrease. DDT exposure suppressed the gene expressions involved in axon development (rab33a and nrxn2a) and potassium channel (kcnq2 and kcnq3). Our results suggest that the hyperactivity and tremor like movement in DDT-exposed embryos/larvae may result from oxidative stress involved with neuronal damage.