Compliance assessment of ambulatory Alzheimer patients to aid therapeutic decisions by healthcare professionals

<p>Abstract</p> <p>Background</p> <p>Compliance represents a major determinant for the effectiveness of pharmacotherapy. Compliance reports summarising electronically compiled compliance data qualify healthcare needs and can be utilised as part of a compliance enhancing intervention. Nevertheless, evidence-based information on a sufficient level of compliance is scarce complicating the interpretation of compliance reports. The purpose of our pilot study was to determine the compliance of ambulatory Alzheimer patients to antidementia drugs under routine therapeutic use using electronic monitoring. In addition, the forgiveness of donepezil (i.e. its ability to sustain adequate pharmacological response despite suboptimal compliance) was characterised and evidence-based guidance for the interpretation of compliance reports was intended to be developed.</p> <p>Methods</p> <p>We determined the compliance of four different antidementia drugs by electronic monitoring in 31 patients over six months. All patients were recruited from the gerontopsychiatric clinic of a university hospital as part of a pilot study. The so called medication event monitoring system (MEMS) was employed, consisting of a vial with a microprocessor in the lid which records the time (date, hour, minute) of every opening. Daily compliance served as primary outcome measure, defined as percentage of days with correctly administered doses of medication. In addition, pharmacokinetics and pharmacodynamics of donepezil were simulated to systematically assess therapeutic undersupply also incorporating study compliance patterns. Statistical analyses were performed with SPSS and Microsoft Excel.</p> <p>Results</p> <p>Median daily compliance was 94% (range 48%-99%). Ten patients (32%) were non-compliant at least for one month. One-sixth of patients taking donepezil displayed periods of therapeutic undersupply. For 10 mg and 5 mg donepezil once-daily dosing, the estimated forgiveness of donepezil was 80% and 90% daily compliance or two and one dosage omissions at steady state, respectively. Based on the simulation findings we developed rules for the evidence-based interpretation of donepezil compliance reports.</p> <p>Conclusions</p> <p>Compliance in ambulatory Alzheimer patients was for the first time assessed under routine conditions using electronic monitoring: On average compliance was relatively high but variable between patients. The approach of pharmacokinetic/pharmacodynamic <it>in silico </it>simulations was suitable to characterise the forgiveness of donepezil suggesting evidence-based recommendations for the interpretation of compliance reports.</p

In vitro pharmacodynamics, pharmacokinetic/pharmacodynamic modelling, in silico simulation and evaluation of dosing regimens for linezolid

Ziel dieser Arbeit war die Entwicklung einer rationalen Hypothese zur optimierten Dosierung des Antibiotikums Linezolid (LZD) bei kritisch kranken Patienten mit schwerer Staphylokokkus (S.) aureus-Infektion. Die antibakterielle Aktivität von LZD gegen S. aureus wurde mittels eines pharmakodynamischen In-vitro-Modellansatzes charakterisiert, wobei die bakterielle Absterbekinetik unter konstanten und in-vivo-ähnlichen LZD-Expositionen untersucht wurde. Die relative bakterielle Reduktion wurde mittels pharmakokinetisch/-pharmakodynamischer (PK/PD) Modellierung analysiert. Das entwickelte PK/PD-Modell wurde mit einem Populations-PK-Modell kombiniert, um via In-silico-Simulation einer 14-tägigen LZD-Therapie die potenzielle Wirksamkeit von 12 hypothetischen Dosierungsschemata für LZD im Vergleich zur Standarddosierung (600 mg 2 x täglich) zu bewerten. Hierbei ergab sich die Hypothese, dass bei diesen kritisch kranken Patienten eine dreimal tägliche Gabe von 600 mg LZD effektiver sein könnte.von Christian Scheeran

Meta-analysis of preclinical measures of efficacy in immune checkpoint blockade therapies and comparison to clinical efficacy estimates

Abstract Background Despite the successes of checkpoint inhibitors targeting T-cell receptors, clinical efficacy is highly cancer-dependent and subject to high inter-individual variability in treatment outcome. The ability to predict the clinical success in different cancer indications is therefore an important capability for successful clinical development. In this meta-analysis, the main goal was to identify factors that modified the clinical efficacy estimates of checkpoint blockade therapies derived from preclinical animal data to improve the robustness and reliability of such estimates. Methods To this end, animal studies testing checkpoint inhibitors (anti-PD-1, anti-PD-L1, anti-CTLA-4) were identified in PubMed ranging from 1.01.2000 to 31.12.2018. The eligibility criteria included the reporting of the Kaplan–Meier estimates of survival and the number of mice used in each experiment. A mixed-effects model was fitted to the preclinical and clinical data separately to determine potential sources of bias and heterogeneity between studies. Results A total of 160 preclinical studies comprising 13,811 mice were selected, from which the hazard ratio (HR) and the median survival ratio (MSR) were calculated. Similarly, clinical Phase III studies of checkpoint inhibitors were identified in PubMed and the ClinicalTrials.gov database ranging from 1.01.2010 to 31.12.2020. This resulted in 62 clinical studies representing 43,135 patients subjected to 8 therapies from which overall survival (OS) and progression-free survival (PFS) hazard ratios were obtained. Using a mixed-effects model, different factors were tested to identify sources of variability between estimates. In the preclinical data, the tumor cell line and individual study were the main factors explaining the heterogeneity. In the clinical setting, the cancer type was influential to the inter-study variability. When using the preclinical estimates to predict clinical estimates, the cancer-type specific estimates of treatment effect using the MSRs better approximated the observed clinical estimates than the HR-derived predictions. Conclusions This has strong implications on the design of ICB preclinical studies with respect to sample size determination, selection of cancer cell lines and labs to run the experiments and the choice of efficacy measure

Pharmacodynamics, pharmacokinetics and CYP3A4 interaction potential of the selective P2X3 receptor antagonist filapixant: A randomized multiple ascending-dose study in healthy young men

Aims: We report on investigations exploring the P2X3-receptor antagonist filapixant's effect on taste perception and cough-reflex sensitivity and describe its pharmacokinetics, including its CYP3A4-interaction potential. Methods: In a randomized, placebo-controlled, double-blind study, 3 × 12 healthy men (18-45 years) were assigned (3:1) to filapixant (20, 80 or 250 mg by mouth) or placebo twice daily over 2 weeks. A single dose of midazolam (1 mg), a CYP3A4 substrate, was administered with and without filapixant. Assessments included a taste-strips test, a taste questionnaire, cough challenge with adenosine triphosphate, adverse event reports and standard safety assessments. Results: Taste disturbances were observed mainly in the 250-mg group: six of nine participants (67%) in this group reported hypo- or dysgeusia in the questionnaire; eight participants (89%) reported taste-related adverse events. Five participants (56%) had a decrease in overall taste-strips-test scores ≥2 points (point estimate −1.1 points, 90% confidence interval [−3.3; 1.1]). Cough counts increased with adenosine triphosphate concentration but without major differences between treatments. Filapixant exposure increased proportionally to dose. Co-administration of filapixant had no clinically relevant effect on midazolam pharmacokinetics. Area under the concentration-time curve ratios and 90% confidence intervals were within 80-125%. No serious or severe adverse events were reported. Conclusions: Overall, filapixant was safe and well tolerated, apart from mild, transient taste disturbances. Such disturbances occurred more frequently than expected based on (in vitro) receptor-selectivity data, suggesting that other factors than P2X3:P2X2/3 selectivity might also play an important role in this context. The cough-challenge test showed no clear treatment effect. Filapixant has no clinically relevant CYP3A4 interaction potential

Safety, Pharmacodynamics, and Pharmacokinetics of P2X3 Receptor Antagonist Eliapixant (BAY 1817080) in Healthy Subjects: Double-Blind Randomized Study

BACKGROUND AND OBJECTIVE: There is no licensed treatment for refractory chronic cough; off-label therapies have limited efficacy and can produce adverse effects. Excessive adenosine triphosphate signaling via P2X3 receptors is implicated in refractory chronic cough, and selective P2X3 receptor antagonists such as eliapixant (BAY 1817080) are under investigation. The objective of the study was to investigate the safety and tolerability of ascending repeated oral doses of eliapixant in healthy volunteers. METHODS: We conducted a repeated-dose, double-blind, randomized, placebo-controlled study in 47 healthy male individuals. Subjects received repeated twice-daily ascending oral doses of eliapixant (10, 50, 200, and 750 mg) or placebo for 2 weeks. The primary outcome was frequency and severity of adverse events. Other outcomes included pharmacokinetics and evaluation of taste disturbances, which have occurred with the less selective P2X3 receptor antagonist gefapixant. RESULTS: Peak plasma concentrations of eliapixant were reached 3–4 h after administration of the first and subsequent doses. With multiple dosing, steady-state plasma concentrations were reached after ~ 6 days, and plasma concentrations predicted to achieve ≥ 80% P2X3 receptor occupancy (the level required for efficacy) were reached at 200 and 750 mg. Increases in plasma concentrations with increasing doses were less than dose proportional. After multiple dosing, mean plasma concentrations of eliapixant showed low peak–trough fluctuations and were similar for 200- and 750-mg doses. Eliapixant was well tolerated with a low incidence of taste-related adverse events. CONCLUSIONS: Eliapixant (200 and 750 mg) produced plasma concentrations that cover the predicted therapeutic threshold over 24 h, with good safety and tolerability. These results enabled eliapixant to progress to clinical trials in patients with refractory chronic cough. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov: NCT03310645 (initial registration: 16 October, 2017). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40262-022-01126-1

Hepatotoxicity of AKR1C3 Inhibitor BAY1128688: Findings from an Early Terminated Phase IIa Trial for the Treatment of Endometriosis

Abstract Introduction BAY1128688 is a selective inhibitor of aldo-keto reductase family 1 member C3 (AKR1C3), an enzyme implicated in the pathology of endometriosis and other disorders. In vivo animal studies suggested a potential therapeutic application of BAY1128688 in treating endometriosis. Early clinical studies in healthy volunteers supported the start of phase IIa. Objective This manuscript reports the results of a clinical trial (AKRENDO1) assessing the effects of BAY1128688 in adult premenopausal women with endometriosis-related pain symptoms over a 12-week treatment period. Methods Participants in this placebo-controlled, multicenter phase IIa clinical trial (NCT03373422) were randomized into one of five BAY1128688 treatment groups: 3 mg once daily (OD), 10 mg OD, 30 mg OD, 30 mg twice daily (BID), 60 mg BID; or a placebo group. The efficacy, safety, and tolerability of BAY1128688 were investigated. Results Dose-/exposure-dependent hepatotoxicity was observed following BAY1128688 treatment, characterized by elevations in serum alanine transferase (ALT) occurring at around 12 weeks of treatment and prompting premature trial termination. The reduced number of valid trial completers precludes conclusions regarding treatment efficacy. The pharmacokinetics and pharmacodynamics of BAY1128688 among participants with endometriosis were comparable with those previously found in healthy volunteers and were not predictive of the subsequent ALT elevations observed. Conclusions The hepatotoxicity of BAY1128688 observed in AKRENDO1 was not predicted by animal studies nor by studies in healthy volunteers. However, in vitro interactions of BAY1128688 with bile salt transporters indicated a potential risk factor for hepatotoxicity at higher doses. This highlights the importance of in vitro mechanistic and transporter interaction studies in the assessment of hepatoxicity risk and suggests further mechanistic understanding is required. Clinical Trial Registration NCT03373422 (date registered: November 23, 2017