Proposal for a new study design and endpoint in research on medication history taking.

Introduction: Medication history errors at hospital admission are common and effective strategies to improve the quality of medication histories are still being researched. However, studies on new approaches regarding medication history taking are often time-consuming and resource-intensive. The gold standard when evaluating the quality of medication histories is the comparison of a Best Possible Medication History to the original. However, this double collection requires significant resources, disrupts clinical procedures, and places an additional burden on patients. Therefore, more efficient study designs need to be explored. We aimed to develop a design for future studies on medication history taking that uses fewer research resources and places less strain on patients and staff. Discussion: We first identified shortcomings of the established study designs on medication history taking and subsequently defined requirements for a new design. A pragmatic study with an alternative endpoint was identified in a previous literature search. It served as the starting point from which we developed a new study design to assess the quality of approaches to medication history taking. Instead of taking a second medication history, a patient's pre-existing medication document can be used as comparator to determine the quality of the medication history. Furthermore, we defined a new primary endpoint, i.e. the number of updates per patient. Updates are differences between the newly acquired medication history and the comparator. They include discontinued, initiated, and changed medications. To enhance our proposed design, we recommend a preparatory phase to identify a suitable comparator document, and a baseline phase to assess the current process. Conclusion: We propose a more resource-efficient study design with a new endpoint. We plan to test its feasibility and evaluate whether it could enhance the efficacy of research on medication history taking in a pilot project.

Dose-dependent induction of CYP3A activity by St. John's wort alone and in combination with rifampin.

The dose dependence of the effect of enzyme inducers and the effect of the combined administration of two inducers that exert their effect via the same induction pathway (pregnane X receptor) have not been well studied. Using oral midazolam microdoses (30 µg), we have investigated CYP3A4 induction by St. John's wort (SJW) in 11 healthy volunteers using low (300 mg/day containing 7.48 mg hyperforin), therapeutic (900 mg/day), and supratherapeutic doses of SJW (1800 mg/day) for 14 days. SJW was then co-administered with rifampin (600 mg/day) for a further 7 days to evaluate the effect of the combined administration of two inducers. In addition, intravenous midazolam microdoses (10 µg) were administered before SJW, at SJW 1800 mg/day, and during administration of the two inducers to assess the hepatic contribution to total induction (semi-simultaneous administration). Administration of SJW increased oral midazolam clearance 1.96-fold (300 mg/day), 3.86-fold (900 mg/day), and 5.62-fold (1800 mg/day), and 17.5-fold after the addition of rifampin. Concurrently, the clearance of intravenous midazolam increased 2.05-fold (1800 mg/day) and 2.93-fold (SJW + rifampin). These results show that rifampin significantly enhances the induction of the highest SJW doses both hepatically and overall and suggest that these metabolic effects occur predominantly in the gut. These findings also suggest that in drug interactions involving strong and moderate enzyme inducers, the perpetrator effects of the strong inducer are decisive for the interaction.

Event Analysis for Automated Estimation of Absent and Persistent Medication Alerts: Novel Methodology.

Background: Event analysis is a promising approach to estimate the acceptance of medication alerts issued by computerized physician order entry (CPOE) systems with an integrated clinical decision support system (CDSS), particularly when alerts cannot be interactively confirmed in the CPOE-CDSS due to its system architecture. Medication documentation is then reviewed for documented evidence of alert acceptance, which can be a time-consuming process, especially when performed manually. Objective: We present a new automated event analysis approach, which was applied to a large data set generated in a CPOE-CDSS with passive, noninterruptive alerts. Methods: Medication and alert data generated over 3.5 months within the CPOE-CDSS at Heidelberg University Hospital were divided into 24-hour time intervals in which the alert display was correlated with associated prescription changes. Alerts were considered "persistent" if they were displayed in every consecutive 24-hour time interval due to a respective active prescription until patient discharge and were considered "absent" if they were no longer displayed during continuous prescriptions in the subsequent interval. Results: Overall, 1670 patient cases with 11,428 alerts were analyzed. Alerts were displayed for a median of 3 (IQR 1-7) consecutive 24-hour time intervals, with the shortest alerts displayed for drug-allergy interactions and the longest alerts displayed for potentially inappropriate medication for the elderly (PIM). Among the total 11,428 alerts, 56.1% (n=6413) became absent, most commonly among alerts for drug-drug interactions (1915/2366, 80.9%) and least commonly among PIM alerts (199/499, 39.9%). Conclusions: This new approach to estimate alert acceptance based on event analysis can be flexibly adapted to the automated evaluation of passive, noninterruptive alerts. This enables large data sets of longitudinal patient cases to be processed, allows for the derivation of the ratios of persistent and absent alerts, and facilitates the comparison and prospective monitoring of these alerts.

[Quality of medication documentation in patients discharge summaries after implementing new legal requirements]. / Dokumentationsqualität der Medikation in Entlassbriefen ­ eine Bestandsaufnahme nach Einführung des Rahmenvertrags Entlassmanagement.

INTRODUCTION: Discharge from hospital is a risk to drug continuity and medication safety. In Germany, new legal requirements concerning the management of patient discharge from the hospital came into force in 2017. They set minimum requirements for the documentation of medications in patient discharge summaries, which are the primary means of communication at transitions of care. Six years later, data on their practical implementation in routine care are lacking. METHODS: Within the scope of an explorative retrospective observational study, the minimum requirements were operationalized and a second set of assessment criteria was derived from the recommendation "Good Prescribing Practice in Drug Therapy" published by the Aktionsbündnis Patientensicherheit e.V. as a comparative quality standard. A sample of discharge summaries was drawn from routine care at the University Hospital Heidelberg and assessed according to their fulfilment of the criteria sets. In addition, the potential influence of certain context factors (e. g., involvement of clinical pharmacists or software usage) was evaluated. RESULTS: In total, 11 quality criteria were derived from the minimum requirements. According to the eligibility criteria (i. e., three or more discharge medications) 352 discharge summaries (42 wards; issued in May-July 2021), containing in total 3,051 medications, were included. The practical implementation of the minimum requirements for documenting medications in patient discharge summaries differed considerably depending on the criterion and defined context factors. Core elements (i. e., drug name, strength, and dosage at discharge) were fulfilled in 82.8 %, while further minimum requirements were rarely met or completely lacking (e. g., explanations for special pharmaceutical forms). Involvement of clinical pharmacists and usage of software were shown to be a facilitator of documentation quality, while on-demand medication (compared to long-term medication) as well as newly prescribed medication (compared to home medication or medication changed during hospitalisation) showed poorer documentation quality. In addition, the documentation quality seemed to depend on the department and the day of discharge. CONCLUSION: To date, the wording of the German legal requirements allows for different interpretations without considering the respective clinical setting and the medication actually prescribed. For future clarification of the requirements, implications of the wording for the clinical setting should be considered.

Exploring the heterogeneity in community pharmacist-led medication review studies - A systematic review.

BACKGROUND: Findings on the effectiveness of medication reviews led by community pharmacists (CPs) are often inconclusive. It has been hypothesized that studies are not sufficiently standardized, and thus, it is difficult to draw conclusions. OBJECTIVE(S): To examine differences in the way CP-led medication review studies are set up. This was accomplished by investigating (1) patient selection criteria, (2) components of the medication review interventions, (3) types of outcomes, and (4) measurement instruments used. METHODS: A systematic literature search of randomized controlled trials of CP-led medication reviews was carried out in PubMed and Cochrane Library. Information on patient selection, intervention components, and outcome measurements was extracted, and frequencies were analyzed. Where possible, outcomes were mapped to the Core Outcome Set (COS) for medication review studies. Finally, a network analysis was conducted to explore the influence of individual factors on outcome effects. RESULTS: In total, 30 articles (26 studies) were included. Most articles had a drug class-specific or disease-specific patient selection criterion (n = 19). Half of the articles included patients aged ≥60 years (n = 15), and in 40% (n = 12/30) patients taking 4 drugs or more. In 24 of 30 articles, a medication review was comprised with additional interventions, such as distribution of educational material and training or follow-up visits. About 40 different outcomes were extracted. Within specific outcomes, the measurement instruments varied, and COS was rarely represented. CONCLUSION: The revealed differences in patient selection, intervention delivery, and outcome assessment highlight the need for more standardization in research on CP-led medication reviews. While intervention delivery should be more precisely described to capture potential differences between interventions, outcome assessment should be standardized in terms of outcome selection by application of the COS, and with regard to the selected core outcome measurement instruments to enable comparison of the results.

Lack of CYP3A4 protein induction despite mRNA induction in primary hepatocytes exposed to rifabutin as a possible explanation for its low interaction risk in vivo.

Rifampicin is a strong inducer of cytochrome P450 (CYP3A4) and P-glycoprotein (P-gp/ABCB1), leading to profound drug-drug interactions. In contrast, the chemically related rifabutin does not show such pronounced induction properties in vivo. The aim of our study was to conduct a comprehensive analysis of the different induction potentials of rifampicin and rifabutin in primary human hepatocytes and to analyze the mechanism of potential differences. Therefore, we evaluated CYP3A4/ABCB1 mRNA expression (polymerase chain reaction), CYP3A4/P-gp protein expression (immunoaffinity-liquid chromatography-mass spectrometry, IA-LC-MS/MS), CYP3A4 activity (testosterone hydroxylation), and considered intracellular drug uptake after treatment with increasing rifamycin concentrations (0.01-10 µM). Furthermore, rifamycin effects on the protein levels of CYP2C8, CYP2C9, and CYP2C19 were analyzed (IA-LC-MS/MS). Mechanistic analysis included the evaluation of possible suicide CYP3A4 inhibition (IC50 shift assay) and drug impact on translational efficiency (cell-free luminescence assays). Rifabutin accumulated 6- to 15-fold higher in hepatocytes than rifampicin, but induced CYP3A4 mRNA comparably to rifampicin (e. g. rifampicin 61-fold vs. rifabutin 44-fold, 72 h). While rifampicin for example enhanced protein (10 µM: 21-fold) and activity levels considerably (53-fold), rifabutin only slightly increased CYP3A4 protein expression (10 µM: 3.3-fold) or activity (11-fold) compared to rifampicin after 72 h. Both rifamycins similarly influenced expression of other eliminating proteins. A potential CYP3A4 suicide inhibition by a specific rifabutin metabolite or disruption of ribosome function were excluded experimentally. In conclusion, the lack of protein enhancement, could explain rifabutin's weaker induction-related drug-drug interaction risk in vivo.

Coadministration of fluconazole to boost subtherapeutic sirolimus concentrations: A case report.

Individual sirolimus whole blood concentrations are highly variable, critically influenced by the concomitant use of cytochrome P450 (CYP) 3A inducers or inhibitors, and also modulated by food. Therapeutic drug monitoring is therefore recommended, especially at treatment start or in circumstances that can influence sirolimus exposure. In this case report, we highlight the challenge of achieving therapeutic sirolimus concentrations and present pragmatic solutions with regimen adaptions, pharmacokinetic enhancement (use of a drug­drug interaction), concentration monitoring, and subsequent modeling of population pharmacokinetics to support treatment decisions. In a 69-year-old female patient with allogeneic hematopoietic stem cell transplantation, sirolimus concentrations were stable until she developed cerebral toxoplasmosis with tonic­clonic seizures. During treatment of this acute infection, sirolimus concentrations dropped to subtherapeutic levels and remained largely unaffected by dose increases. [Correction added on 4 May 2024, after first online publication: The word "tacrolimus concentrations" has been changed to "sirolimus concentrations" in the preceding sentence.] Only the simultaneous administration of the CYP3A4 inhibitor fluconazole and a shortening of the sirolimus dosing intervals to a (non-approved) twice-daily administration led to successful control of the concentrations, which ultimately even made a dose reduction possible. This intervention resulted in an increase of sirolimus mean trough concentration to 5.85 ng/mL, i.e., into the desired target range. Additionally, a higher ratio of sirolimus trough levels/daily dose from 26.9 to 109 ng/mL/mg/kg/day was achieved with the initiation of fluconazole. Thus, this case report describes the use of clinical pharmacological concepts and pharmacokinetic modeling to optimize treatment strategies in an individual patient. This strategy could be generalized to other CYP inhibitors and other treatment regimens.

Approaches to medication history taking in different hospital settings: A scoping review.

PURPOSE: A comprehensive medication history can contribute to safe therapy. Many approaches aiming to improve medication history taking require significant human resources. To design an efficient process that delivers high-quality medication histories, the individual requirements and resources of a given setting need to be considered. We aimed to provide an overview of existing approaches to medication history taking and their performance in different settings to potentially support the selection of an appropriate procedure. METHODS: We searched 3 literature databases (PubMed/MEDLINE, CINAHL, PsycINFO) for publications on approaches to medication history taking and analyzed them with regard to their key components as well as the setting, patient population, assessed outcomes, and efficacy. RESULTS: In total, 65 publications were included and analyzed. The majority of the reported approaches relied on involvement of dedicated staff (n = 43), followed by process-oriented interventions (eg, checklists; n = 15) and information technology (IT)-guided interventions (n = 11). A mean (SD) of 6 (2.9) outcomes were described in each study. Medication discrepancies were reported in 89% of all studies, yet about 75 different descriptions of this outcome were used, making it difficult to compare study results. Only 11 studies applied a sample size calculation and statistical tests. Of those, 10 reported a positive effect of their respective intervention on the quality of medication histories. CONCLUSION: Most approaches focused on pharmacy staff, which are associated with considerable cost and resources. Therefore, IT-based approaches and patient engagement should be investigated as cost-effective alternatives and tested for superiority in the same setting. Reporting guidelines and standardized methodology are needed to improve the comparability of such studies.

RNA is a pro-apoptotic target of cisplatin in cancer cell lines and C. elegans.

Cisplatin not only targets DNA but also RNA. However, it is largely unknown whether platinated RNA (Pt-RNA) causes apoptosis and thus contributes to the cytotoxic effects of cisplatin. Consequently, cellular RNA was isolated from HepG2 and LS180 cells, exposed to cisplatin, and the resulting Pt-RNA (20 ng Pt/µg RNA) was transfected into these cancer cell lines or used to treat an apoptosis reporter Caenorhabditis elegans (C. elegans) strain (MD701, expressing CED-1::GFP). Cellular and molecular effects of Pt-RNA were evaluated by luminogenic caspase 3/7 assays, PCR array analysis, and fluorescence microscopy-based quantification of apoptosis in C. elegans gonads. Assuming RNA cross-linking (pseudo double-stranded RNA), the contribution of the Toll-like receptor 3 (TLR3, a sensor of double-stranded RNA) to apoptosis induction in cancer cell lines was investigated by pharmacological TLR3 inhibition and overexpression. In contrast to controls, Pt-RNA significantly enhanced apoptosis in C. elegans (2-fold) and in the cancer cell lines (2-fold to 4-fold). TLR3 overexpression significantly enhanced the pro-apoptotic effects of Pt-RNA in HepG2 cells. TLR3 inhibition reduced the pro-apoptotic effects of Pt-RNA and cisplatin, but not of paclitaxel (off-target control). Gene expression analysis showed that Pt-RNA (but not RNA) significantly enhanced the mRNA levels of nuclear factor kappa B subunit 2 and interleukin-8 in HepG2 cells, suggesting that Pt-RNA is a damage-associated molecular pattern that additionally causes pro-inflammatory responses. Together, this data suggests that not only DNA but also cellular RNA is a functionally relevant target of cisplatin, leading to pro-apoptotic and immunogenic effects.

Time Course of the Interaction Between Oral Short-Term Ritonavir Therapy with Three Factor Xa Inhibitors and the Activity of CYP2D6, CYP2C19, and CYP3A4 in Healthy Volunteers.

BACKGROUND: We investigated the effect of a 5-day low-dose ritonavir therapy, as it is used in the treatment of COVID-19 with nirmatrelvir/ritonavir, on the pharmacokinetics of three factor Xa inhibitors (FXaI). Concurrently, the time course of the activities of the cytochromes P450 (CYP) 3A4, 2C19, and 2D6 was assessed. METHODS: In an open-label, fixed sequence clinical trial, the effect and duration of a 5-day oral ritonavir (100 mg twice daily) treatment on the pharmacokinetics of three oral microdosed FXaI (rivaroxaban 25 µg, apixaban 25 µg, and edoxaban 50 µg) and microdosed probe drugs (midazolam 25 µg, yohimbine 50 µg, and omeprazole 100 µg) was evaluated in eight healthy volunteers. The plasma concentrations of all drugs were quantified using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods and pharmacokinetics were analysed using non-compartmental analyses. RESULTS: Ritonavir increased the exposure of apixaban, edoxaban, and rivaroxaban, but to a different extent the observed area under the plasma concentration-time curve (geometric mean ratio 1.29, 1.46, and 1.87, respectively). A strong CYP3A4 inhibition (geometric mean ratio > 10), a moderate CYP2C19 induction 2 days after ritonavir (0.64), and no alteration of CYP2D6 were observed. A CYP3A4 recovery half-life of 2.3 days was determined. CONCLUSION: This trial with three microdosed FXaI suggests that at most the rivaroxaban dose should be reduced during short-term ritonavir, and only in patients receiving high maintenance doses. Thorough time series analyses demonstrated differential effects on three different drug-metabolising enzymes over time with immediate profound inhibition of CYP3A4 and only slow recovery after discontinuation. CLINICAL TRIAL REGISTRATION: EudraCT number: 2021-006643-39.

Effect of Tacrolimus Formulation (Prolonged-Release vs Immediate-Release) on Its Susceptibility to Drug-Drug Interactions with St. John's Wort.

Tacrolimus is metabolized by cytochrome P450 3A (CYP3A) and is susceptible to interactions with the CYP3A and P-glycoprotein inducer St. John's Wort (SJW). CYP3A isozymes are predominantly expressed in the small intestine and liver. Prolonged-release tacrolimus (PR-Tac) is largely absorbed in distal intestinal segments and is less susceptible to CYP3A inhibition. The effect of induction by SJW is unknown. In this randomized, crossover trial, 18 healthy volunteers received single oral tacrolimus doses (immediate-release [IR]-Tac or PR-Tac, 5 mg each) alone and during induction by SJW. Concentrations were quantified using ultra-high performance liquid chromatography coupled with tandem mass spectrometry and non-compartmental pharmacokinetics were evaluated. SJW decreased IR-Tac exposure (area under the concentration-time curve) to 73% (95% confidence interval 60%-88%) and maximum concentration (Cmax ) to 61% (52%-73%), and PR-Tac exposure to 67% (55%-81%) and Cmax to 69% (58%-82%), with no statistical difference between the 2 formulations. The extent of interaction appeared to be less pronounced in volunteers with higher baseline CYP3A4 activity and in CYP3A5 expressors. In contrast to CYP3A inhibition, CYP3A induction by SJW showed a similar extent of interaction with both tacrolimus formulations. A higher metabolic baseline capacity appeared to attenuate the extent of induction by SJW.

Acute antiarrhythmic effects of SGLT2 inhibitors-dapagliflozin lowers the excitability of atrial cardiomyocytes.

In recent years, SGLT2 inhibitors have become an integral part of heart failure therapy, and several mechanisms contributing to cardiorenal protection have been identified. In this study, we place special emphasis on the atria and investigate acute electrophysiological effects of dapagliflozin to assess the antiarrhythmic potential of SGLT2 inhibitors. Direct electrophysiological effects of dapagliflozin were investigated in patch clamp experiments on isolated atrial cardiomyocytes. Acute treatment with elevated-dose dapagliflozin caused a significant reduction of the action potential inducibility, the amplitude and maximum upstroke velocity. The inhibitory effects were reproduced in human induced pluripotent stem cell-derived cardiomyocytes, and were more pronounced in atrial compared to ventricular cells. Hypothesizing that dapagliflozin directly affects the depolarization phase of atrial action potentials, we examined fast inward sodium currents in human atrial cardiomyocytes and found a significant decrease of peak sodium current densities by dapagliflozin, accompanied by a moderate inhibition of the transient outward potassium current. Translating these findings into a porcine large animal model, acute elevated-dose dapagliflozin treatment caused an atrial-dominant reduction of myocardial conduction velocity in vivo. This could be utilized for both, acute cardioversion of paroxysmal atrial fibrillation episodes and rhythm control of persistent atrial fibrillation. In this study, we show that dapagliflozin alters the excitability of atrial cardiomyocytes by direct inhibition of peak sodium currents. In vivo, dapagliflozin exerts antiarrhythmic effects, revealing a potential new additional role of SGLT2 inhibitors in the treatment of atrial arrhythmias.

A multidomain intervention against cognitive decline in an at-risk-population in Germany: Results from the cluster-randomized AgeWell.de trial.

INTRODUCTION: We investigated the effectiveness of a multidomain intervention to preserve cognitive function in older adults at risk for dementia in Germany in a cluster-randomized trial. METHODS: Individuals with a Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) risk score ≥ 9 aged 60 to 77 years were recruited. After randomization of their general practitioner (GP), patients received a multidomain intervention (including optimization of nutrition and medication, and physical, social, and cognitive activity) or general health advice and GP treatment as usual over 24 months. Primary outcome was global cognitive performance (composite z score, based on domain-specific neuropsychological tests). RESULTS: Of 1030 participants at baseline, n = 819 completed the 24-month follow-up assessment. No differences regarding global cognitive performance (average marginal effect = 0.010, 95% confidence interval: -0.113, 0.133) were found between groups at follow-up. Perceived restrictions in intervention conduct by the COVID-19 pandemic did not impact intervention effectiveness. DISCUSSION: The intervention did not improve global cognitive performance. HIGHLIGHTS: Overall, no intervention effects on global cognitive performance were detected. The multidomain intervention improved health-related quality of life in the total sample. In women, the multidomain intervention reduced depressive symptoms. The intervention was completed during the COVID-19 pandemic.

The differences in drug disposition gene induction by rifampicin and rifabutin are unlikely due to different effects on important pregnane X receptor (NR1I2) splice variants.

Rifampicin and rifabutin can activate the pregnane X receptor (PXR, NR1I2), thereby inducing pharmacokinetically important genes/proteins and reducing exposure to co-administered drugs. Because induction effects vary considerably between these antibiotics, differences could be due to unequal rifamycin-induced activation or tissue expression of the three major NR1I2 splice variants, PXR.1 (NM_003889), PXR.2 (NM_022002), and PXR.3 (NM_033013). Consequently, PXR activation (PXR reporter gene assays) and mRNA expression levels of total NR1I2, PXR.1, PXR.2, and PXR.3 were investigated by polymerase chain reaction in colon and liver samples from eleven surgical patients, in LS180 cells, and primary human hepatocytes. Compared to the colon, total NR1I2 mRNA expression was higher in the liver. Both tissues showed similar expression levels of PXR.1 and PXR.3, respectively. PXR.2 was not quantifiable in the colon samples. Rifampicin and rifabutin similarly enhanced PXR.1 and PXR.2 activity when transfected into LS180 cells, while PXR.3 could not be activated. In LS180 cells, rifampicin (10 µM) reduced total NR1I2 and PXR.3 expression 2-fold after 24 h, while rifabutin (10 µM) increased total NR1I2, PXR.1, PXR.2, and PXR.3 mRNA by approx. 50% after 96-h exposure. In primary human hepatocytes, rifampicin (10 µM) suppressed total NR1I2, PXR.1, and PXR.3 after 48-h exposure, and rifabutin (10 µM) had no significant impact on total NR1I2 or any of the splice variants studied. In conclusion, both antibiotics activated the studied PXR splice variants similarly but modified their expression differently. While rifampicin can suppress mRNA of PXR forms, rifabutin rather increases their expression levels.

Therapeutic drug monitoring of osimertinib in non-small cell lung cancer and short bowel syndrome: A case report.

Short bowel syndrome (SBS) following extensive intestinal resection is often characterized by impaired absorption of orally administered drugs, including tyrosine kinase inhibitors (TKI). We report the case of a patient with EGFR-mutated non-small cell lung carcinoma treated with 80 mg/day of the TKI osimertinib who achieved partial response of the tumour, but was subsequently subjected to a double-barrelled jejunostomy due to ileus. Due to the development of SBS after the bypass surgery, plasma concentrations of osimertinib were monitored using mass spectrometry. The therapeutic drug monitoring confirmed a malabsorption of osimertinib in the patient (108 ng/mL, which is below the 5th percentile of the expected plasma concentration) and was useful to guide adjustments of TKI dosing in order to achieve adequate blood levels (161 ng/mL after increase of the dose to 120 mg/day) in order to maintain tumour control.

Rifabutin but not rifampicin can partly out-balance P-glycoprotein induction by concurrent P-glycoprotein inhibition through high affinity binding to the inhibitory site.

Physiology-based pharmacokinetic modeling suggests that rifabutin can out-balance P-glycoprotein (P-gp) induction by concurrent P-gp inhibition. However, clinical or experimental evidence for this Janus-faced rifabutin effect is missing. Consequently, LS180 cells were exposed to a moderately (2 µM) and strongly (10 µM) P-gp-inducing concentration of rifampicin or rifabutin for 6 days. Cellular accumulation of the fluorescent P-gp substrate rhodamine 123 was evaluated using flow cytometry, either without (induction only) or with adding rifamycin drug to the cells during the rhodamine 123 efflux phase (induction + potential inhibition). Rhodamine 123 accumulation was decreased similarly by both drugs after 6-day exposure (2 µM: 55% residual fluorescence compared to non-induced cells, P < 0.01; 10 µM: 30% residual fluorescence compared to non-induced cells, P < 0.001), indicating P-gp induction. Rhodamine 123 influx transporters mRNA expressions were not affected, excluding off-target effects. Acute re-exposure to rifabutin, however, considerably re-increased rhodamine 123 accumulation (2 µM induction: re-increase by 55%, P < 0.01; 10 µM induction: 49% re-increase, P < 0.001), suggesting P-gp inhibition. In contrast, rifampicin only had weak effects (2 µM induction: no re-increase; 10 µM induction: 16% re-increase; P < 0.05). Molecular docking analysis eventually revealed that rifabutin has a higher binding affinity to the inhibitor binding site of P-gp than rifampicin (ΔG (kcal/mol) = -11.5 vs -5.3). Together, this study demonstrates that rifabutin can at least partly mask P-gp induction by P-gp inhibition, mediated by high affinity binding to the inhibitory site of P-gp.

Untapped options to reduce waste from blister packaging for tablets and capsules.

PURPOSE: In Europe, most medicines are taken orally and primarily packaged as single solid oral dosage forms (SODF) in blister chambers (alveoli) arranged on blister cards. Blister cards are constructed as multilayer laminates of aluminum (Al) foils and/or various plastic polymers bonded together, forming the alveoli, which are separated by more or less large gaps. We calculated the amount of packaging material (and thus waste) generated annually for the packaging of the most commonly prescribed SODF in Germany and estimated how much waste could be saved by rearranging the alveoli. METHODS: For this purpose, we analysed the SODF of the 50 most frequently prescribed medicines that were packaged in alveoli (N = 45; 13 of aluminum-aluminum blisters, 32 of mixed materials), measured and weighed their packaging material and content, calculated the annual amount of waste produced from them, and estimated how much waste could be saved if the alveoli were optimally positioned on the blister cards. In addition, we examined the variability of the blister packaging of eight groups of commonly prescribed generics of the same strength. RESULTS: Detailed analysis of the blister cards revealed that most of the material (69%) was used for the space between blisters and that aluminum-aluminum alveoli were more than four times larger than the packaged SODF. The (conservatively) estimated annual amount of composite waste generated for the primary packaging of these SODF was 3868 t (and extrapolated to the entire German pharmaceutical market 8533 t), of which an optimized arrangement of the blister chambers, i.e., a 2-mm sealing area around each alveolus and the arrangement of the SODF in 2 rows, would save approximately 37%. CONCLUSION: Considering that other ecological strategies are not yet mature, the optimal arrangement of blister chambers would be a captivatingly simple and, above all, immediately implementable strategy to avoid large amounts of avoidable waste.

Evaluation of Hydroxychloroquine as a Perpetrator on Cytochrome P450 (CYP) 3A and CYP2D6 Activity with Microdosed Probe Drugs in Healthy Volunteers.

BACKGROUND AND OBJECTIVE: Although polypharmacy is a particular challenge in daily rheumatological practice, clinical research on the effects of hydroxychloroquine (HCQ), a commonly used drug for patients with rheumatic diseases, is sparse on cytochrome P450 (CYP)-mediated metabolism. We have shown that pre-treatment with pantoprazole does not alter HCQ absorption in healthy volunteers. In this paper, we report the effects of a single 400 mg dose of HCQ on specific CYP3A and CYP2D6 substrates in healthy volunteers. METHODS: In the trial, participants were randomized into two groups (HCQ plus a 9-day course of pantoprazole, or HCQ only). As a secondary endpoint, the effects of a single oral dose of HCQ on the exposure of the oral microdosed CYP3A probe drug midazolam (30 µg) and the oral microdosed CYP2D6 probe drug yohimbine (50 µg) were studied in 23 healthy volunteers (EudraCT no. 2020-001470-30, registered 31 March 2020). RESULTS: The exposure of the probe drugs after intake of HCQ compared with baseline values was quantified by the partial area under the plasma concentration-time curve 0-6 h after administration (AUC0-6 h) for yohimbine and the partial AUC2-4 h for midazolam. Under HCQ, yohimbine AUC0-6 h was unchanged, independent of CYP2D6 genotypes and pantoprazole exposure. Midazolam AUC2-4 h was 25% higher on the day of HCQ administration than at baseline (p = 0.0007). This significant increase was driven by the pantoprazole subgroup, which showed a 46% elevation of midazolam AUC2-4 h as compared with baseline (p < 0.0001). The ratio of midazolam to 1-OH-midazolam partial AUC2-4 h significantly increased from 3.03 ± 1.59 (baseline) to 3.60 ± 1.56 (HCQ) in the pantoprazole group (p = 0.0026). CONCLUSION: In conclusion, we observed an increased midazolam exposure most likely related to pantoprazole.

Feasibility and Safety of Sildenafil to Repair Brain Injury Secondary to Birth Asphyxia (SANE-01): A Randomized, Double-blind, Placebo-controlled Phase Ib Clinical Trial.

OBJECTIVE: To test feasibility and safety of administering sildenafil in neonates with neonatal encephalopathy (NE), developing brain injury despite therapeutic hypothermia (TH). STUDY DESIGN: We performed a randomized, double-blind, placebo-controlled phase Ib clinical trial between 2016 and 2019 in neonates with moderate or severe NE, displaying brain injury on day-2 magnetic resonance imaging (MRI) despite TH. Neonates were randomized (2:1) to 7-day sildenafil or placebo (2 mg/kg/dose enterally every 12 hours, 14 doses). Outcomes included feasibility and safety (primary outcomes), pharmacokinetics (secondary), and day-30 neuroimaging and 18-month neurodevelopment assessments (exploratory). RESULTS: Of the 24 enrolled neonates, 8 were randomized to sildenafil and 3 to placebo. A mild decrease in blood pressure was reported in 2 of the 8 neonates after initial dose, but not with subsequent doses. Sildenafil plasma steady-state concentration was rapidly reached, but decreased after TH discontinuation. Twelve percent of neonates (1/8) neonates died in the sildenafil group and 0% (0/3) in the placebo group. Among surviving neonates, partial recovery of injury, fewer cystic lesions, and less brain volume loss on day-30 magnetic resonance imaging were noted in 71% (5/7) of the sildenafil group and in 0% (0/3) of the placebo group. The rate of death or survival to 18 months with severe neurodevelopmental impairment was 57% (4/7) in the sildenafil group and 100% (3/3) in the placebo group. CONCLUSIONS: Sildenafil was safe and well-absorbed in neonates with NE treated with TH. Optimal dosing needs to be established. Evaluation of a larger number of neonates through subsequent phases II and III trials is required to establish efficacy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.govNCT02812433.