Time course of CYP3A activity during and after metamizole (dipyrone) in healthy volunteers

BACKGROUND AND PURPOSE

In patients of all ages, metamizole is a frequently used analgesic. Recently, metamizole has been identified as an inducer of, among others, cytochrome P450 (CYP) 3A activity, but the time course of this interaction has not been evaluated.

EXPERIMENTAL APPROACH

Using repeated oral microdoses (30 μg) of the CYP3A index substrate midazolam, we assessed changes in midazolam pharmacokinetics (area under the concentration-time curve from 2-4 h: AUC_2-4 and estimated partial metabolic clearance: eCl_met ) before, at steady-state, and after discontinuation of 3 x 1000 mg metamizole/d orally for 8 d.

KEY RESULTS

Significant changes in pharmacokinetic parameters were detected already three days after start of metamizole treatment. At the steady-state of enzyme induction, the geometric mean ratio of midazolam AUC_2-4 was substantially reduced to 0.18 (90 % confidence interval: 0.14-0.24) with a corresponding 5.43-fold (4.15-7.10) increase of eCl_met . After discontinuation of metamizole, the changes slowly recovered, but were still significant at the end of the observation period on the fifth day after discontinuation of metamizole therapy (AUC_2-4 reduced to 0.50 (0.41-0.63) and eCl_met 1.99-fold increased (1.60-2.47, p < 0.05)).

CONCLUSION AND IMPLICATIONS

Metamizole acts as a strong inducer of CYP3A already few days after start of metamizole administration and, thus, should be avoided in patients using drugs with narrow therapeutic index and major clearance via CYP3A. If their administration is essential, close monitoring and dose adjustment of co-medication should be performed as early as the first week after the initiation and after discontinuation of metamizole therapy.

The first-in-class ERK inhibitor ulixertinib shows promising activity in mitogen-activated protein kinase (MAPK)-driven pediatric low-grade glioma models

BACKGROUND

Pediatric low-grade gliomas (pLGG) are the most common pediatric central nervous system tumors, with driving alterations typically occurring in the MAPK pathway. The ERK1/2 inhibitor ulixertinib (BVD-523) has shown promising responses in adult patients with mitogen-activated protein kinase (MAPK)-driven solid tumors.

METHODS

We investigated the antitumoral activity of ulixertinib monotherapy as well as in combination with MEK inhibitors (MEKi), BH3-mimetics, or chemotherapy in pLGG. Patient-derived pLGG models reflecting the two most common alterations in the disease, KIAA1549:BRAF-fusion and BRAFV600E mutation (DKFZ-BT66 and BT40, respectively) were used for in vitro and in vivo (zebrafish embryos and mice) efficacy testing.

RESULTS

Ulixertinib inhibited MAPK pathway activity in both models, and reduced cell viability in BT40 with clinically achievable concentrations in the low nanomolar range. Combination treatment of ulixertinib with MEKi or BH3-mimetics showed strong evidence of antiproliferative synergy in vitro. Ulixertinib showed on-target activity in all tested combinations. In vivo, sufficient penetrance of the drug into brain tumor tissue in concentrations above the in vitro IC50 and reduction of MAPK pathway activity was achieved. In a preclinical mouse trial, ulixertinib mono- and combined therapies slowed tumor growth and increased survival.

CONCLUSIONS

These data indicate a high clinical potential of ulixertinib for the treatment of pLGG and strongly support its first clinical evaluation in pLGG as single agent and in combination therapy in a currently planned international phase I/II umbrella trial.

Effect of Clomethiazole Vs. Clorazepate on Hepatic Fat and Serum Transaminase Activities in Alcohol-Associated Liver Disease: Results from a Randomized, Controlled Phase II Clinical Trial

AIMS

Alcohol-associated liver disease (ALD) is a global health problem caused, among other factors, by oxidative stress from the formation of reactive oxygen species (ROS). One important source of ROS is microsomal ethanol metabolism catalyzed by cytochrome P450 2E1 (CYP2E1), which is induced by chronic ethanol consumption. Inhibition of CYP2E1 by clomethiazole (CMZ) decreases oxidative stress in cell cultures and improves ALD in animal studies. Our study aimed to assess the benefits of a CYP2E1 inhibitor (clomethiazole) in detoxification of patients with ALD.

METHODS

Open label, randomized controlled clinical trial to study whether CYP2E1 inhibition improves ALD in the patients with alcohol use disorders admitted for alcohol detoxification therapy (ADT). Patients had to have a serum aspartate aminotransferase (AST) activity exceeding twice the upper normal limit at time of admission and be non-cirrhotic defined by fibroscan value <12 kPa. Sixty patients were randomly assigned to ADT with either CMZ or clorazepate (CZP) for 7-10 days in a 1:1 ratio. The chlorzoxazone test of CYP2E1 activity was performed at enrolment and at 2 points during the study.

RESULTS

ADT improved hepatic steatosis (controlled attenuation parameter) in both groups significantly. A trend towards a greater improvement in hepatic fat content during ADT (-21.5%) was observed in the CMZ group (252 ± 48 dB/m vs. 321 ± 38 dB/m; P < 0.0001) compared with the CZP group (-13.9%; 273 ± 38 dB/m vs. 317 ± 39 dB/m; P < 0.0001). As already reported, serum AST (P < 0.004) and alanine aminotransferase (ALT) activities (P < 0.0006) significantly decreased in CMZ patients as compared with patients on CZP by the end of hospitalization. A significant correlation was found between AST (P = 0.023), ALT (P = 0.009), GGT (P = 0.039) and CAP.

CONCLUSION

This study demonstrates that CMZ improves clinical biomarkers for ALD in humans most likely due to its inhibitory effect on CYP2E1. Because of its addictive potential, CMZ can only be given for a short period of time and therefore other CYP2E1 inhibitors to treat ALD are needed.

Correction: Bay et al. Functional Characterization of the Solute Carrier LAT-1 (SLC7A5/SLC3A2) in Human Brain Capillary Endothelial Cells with Rapid UPLC-MS/MS Quantification of Intracellular Isotopically Labelled L-Leucine. Int. J. Mol. Sci. 2022, 23, 3637

The authors would like to make the following corrections to the publication [...].

Effect of Clarithromycin, a Strong CYP3A and P-glycoprotein Inhibitor, on the Pharmacokinetics of Edoxaban in Healthy Volunteers and the Evaluation of the Drug Interaction with Other Oral Factor Xa Inhibitors by a Microdose Cocktail Approach

PURPOSE

We assessed the differential effect of clarithromycin, a strong inhibitor of cytochrome P450 (CYP) 3A4 and P-glycoprotein, on the pharmacokinetics of a regular dose of edoxaban and on a microdose cocktail of factor Xa inhibitors (FXaI). Concurrently, CYP3A activity was determined with a midazolam microdose.

METHODS

In an open-label fixed-sequence trial in 12 healthy volunteers, the pharmacokinetics of a microdosed FXaI cocktail (μ-FXaI; 25 μg apixaban, 50 μg edoxaban, and 25 μg rivaroxaban) and of 60 mg edoxaban before and during clarithromycin (2 x 500 mg/d) dosed to steady-state was evaluated. Plasma concentrations of study drugs were quantified using validated ultra-performance liquid chromatography-tandem mass spectrometry methods.

RESULTS

Therapeutic clarithromycin doses increased the exposure of a therapeutic 60 mg dose of edoxaban with a geometric mean ratio (GMR) of the area under the plasma concentration-time curve (AUC) of 1.53 (90 % CI: 1.37-1.70; p < 0.0001). Clarithromycin also increased the GMR (90% CI) of the exposure of microdosed FXaI apixaban to 1.38 (1.26-1.51), edoxaban to 2.03 (1.84-2.24), and rivaroxaban to 1.44 (1.27-1.63). AUC changes observed for the therapeutic edoxaban dose were significantly smaller than those observed with the microdose (p < 0.001).

CONCLUSION

Clarithromycin increases FXaI exposure. However, the magnitude of this drug interaction is not expected to be clinically relevant. The edoxaban microdose overestimates the extent of the drug interaction with the therapeutic dose, whereas AUC ratios for apixaban and rivaroxaban were comparable to the interaction with therapeutic doses as reported in the literature.

TRIAL REGISTRATION

EudraCT Number: 2018-002490-22.

Frailty as a Marker for the Plasma Concentrations of Direct Oral Anticoagulants in Older Patients: Results of an Exploratory Study

BACKGROUND

Frailty makes older adults vulnerable to adverse health outcomes and can modify pharmacokinetics and drug exposure.

OBJECTIVE

We aimed to explore the relationship between different frailty assessments and trough plasma concentrations of direct oral anticoagulants in older patients.

METHODS

The frailty status of adults aged ≥ 70 years receiving regular direct oral anticoagulant medication was assessed by four different instruments: Fried physical phenotype, Rockwood frailty index, Short Physical Performance Battery, and FRAIL scale. The two performance measures "slow gait speed" and "weak grip strength" were used to build a separate score depending on the number of positive criteria (none, one, two). For each participant, a single steady-state direct oral anticoagulant trough plasma concentration was collected, dose-normalized, and its relationship to the various frailty assessments analyzed.

RESULTS

Forty-two participants completed the study, with most using apixaban (n = 22). Dose-normalized apixaban trough concentrations were 2.48-fold higher in frail participants (Fried phenotype) than in robust participants (p = 0.009) and correlated positively with Fried physical phenotype (r_s = 0.535, p = 0.010) and negatively with Short Physical Performance Battery (r_s = - 0.434, p = 0.044). Compared with participants who met none of the criteria "slow gait speed" and "weak grip strength", apixaban trough concentrations were approximately 1.9-fold higher in participants who were positive for one (p = 0.018) or two (p = 0.013) of these measures.

CONCLUSIONS

In this exploratory study, higher levels of frailty on performance-based frailty assessments were associated with higher apixaban exposure in older adults.

CLINICAL TRIAL REGISTRATION

German Clinical Trials Register DRKS00016741; registered 20 February, 2019.

Important Requirements for Desorption/Ionization Mass Spectrometric Measurements of Temozolomide-Induced 2'-Deoxyguanosine Methylations in DNA

In clinical pharmacology, drug quantification is mainly performed from the circulation for pharmacokinetic purposes. Finely monitoring the chemical effect of drugs at their chemical sites of action for pharmacodynamics would have a major impact in several contexts of personalized medicine. Monitoring appropriate drug exposure is particularly challenging for alkylating drugs such as temozolomide (TMZ) because there is no flow equilibrium that would allow reliable conclusions to be drawn about the alkylation of the target site from plasma concentrations. During the treatment of glioblastoma, it appears, therefore, promising to directly monitor the alkylating effect of TMZ rather than plasma exposure, ideally at the site of action. Mass spectrometry (MS) is a method of choice for the quantification of methylated guanines and, more specifically, of O6-methylguanines as a marker of TMZ exposure at the site of action. Depending on the chosen strategy to analyze modified purines and 2'-deoxynucleosides, the analysis of methylated guanines and 2'-deoxyguanosines is prone to important artefacts due to the overlap between masses of (i) guanines from DNA and RNA, and (ii) different methylated species of guanines. Therefore, the specific analysis of O6-methyl-2'deoxyguanosine, which is the product of the TMZ effect, is highly challenging. In this work, we report observations from matrix-assisted laser desorption/ionization (MALDI), and desorption electrospray ionization (DESI) MS analyses. These allow for the construction of a decision tree to initiate studies using desorption/ionization MS for the analysis of 2'-deoxyguanosine methylations induced by TMZ.

Anticholinergic burden measures, symptoms, and fall-associated risk in older adults with polypharmacy: Development and validation of a prognostic model

BACKGROUND

Anticholinergic burden has been associated with adverse outcomes such as falls. To date, no gold standard measure has been identified to assess anticholinergic burden, and no conclusion has been drawn on which of the different measure algorithms best predicts falls in older patients from general practice. This study compared the ability of five measures of anticholinergic burden to predict falls. To account for patients' individual susceptibility to medications, the added predictive value of typical anticholinergic symptoms was further quantified in this context.

METHODS AND FINDINGS

To predict falls, models were developed and validated based on logistic regression models created using data from two German cluster-randomized controlled trials. The outcome was defined as "≥ 1 fall" vs. "no fall" within a 6-month follow-up period. Data from the RIME study (n = 1,197) were used in model development, and from PRIMUM (n = 502) for external validation. The models were developed step-wise in order to quantify the predictive ability of anticholinergic burden measures, and anticholinergic symptoms. In the development set, 1,015 patients had complete data and 188 (18.5%) experienced ≥ 1 fall within the 6-month follow-up period. The overall predictive value of the five anticholinergic measures was limited, with neither the employed anticholinergic variable (binary / count / burden), nor dose-dependent or dose-independent measures differing significantly in their ability to predict falls. The highest c-statistic was obtained using the German Anticholinergic Burden Score (0.73), whereby the optimism-corrected c-statistic was 0.71 after interval validation using bootstrapping and 0.63 in the external validation. Previous falls and dizziness / vertigo had the strongest prognostic value in all models.

CONCLUSIONS

The ability of anticholinergic burden measures to predict falls does not appear to differ significantly, and the added value they contribute to risk classification in fall-prediction models is limited. Previous falls and dizziness / vertigo contributed most to model performance.

Evaluation of the drug-drug interaction potential of the novel hepatitis B and D virus entry inhibitor bulevirtide at OATP1B in healthy volunteers

Introduction: Bulevirtide is a first-in-class antiviral drug to treat chronic hepatitis B/D. We investigated the drug-drug interaction potential and pharmacokinetics of high-dose subcutaneous bulevirtide (5 mg twice daily) with organic anion transporting polypeptide 1B1 (OATP1B1) and cytochrome P450 (CYP) 3A4. Methods: This was a single-center, open-label, fixed-sequence drug-drug interaction trial in 19 healthy volunteers. Before and at bulevirtide steady state, participants ingested a single 40 mg dose of pravastatin. A midazolam microdose was applied to quantify CYP3A4 activity. Results: At bulevirtide steady state, pravastatin area under the concentration-time curve (AUC_0-∞) increased 1.32-fold (90% CI 1.08-1.61). The 5 mg bulevirtide twice-daily treatment resulted in a mean AUC_0-12 of 1210 h*ng/ml (95% CI 1040-1408) and remained essentially unchanged under the influence of pravastatin. CYP3A4 activity did not change to a clinically relevant extent. As expected, total bile acids increased substantially (35-fold) compared to baseline during bulevirtide treatment. All study medication was well tolerated. Discussion: The study demonstrated that high-dose bulevirtide inhibited OATP1B-mediated hepatic uptake of the marker substrate pravastatin but the extent is considered clinically not relevant. Changes in CYP3A4 activity were also not clinically relevant. In conclusion, this study suggests that OATP1B substrate drugs as well as CYP3A4 substrates may safely be used without dose adjustment in patients treated with bulevirtide. However, in patients using high statin doses and where concomitant factors potentially further increase statin exposure, caution may be required when using bulevirtide.

Safety and efficacy of bulevirtide in combination with tenofovir disoproxil fumarate in patients with hepatitis B virus and hepatitis D virus coinfection (MYR202): a multicentre, randomised, parallel-group, open-label, phase 2 trial

BACKGROUND

Bulevirtide is a first-in-class peptidic entry inhibitor for hepatitis B virus (HBV) and hepatitis D virus infection. In July, 2020, bulevirtide 2 mg received conditional marketing authorisation by the European Medical Agency for treatment of chronic hepatitis D virus infection. We investigated the antiviral activity of bulevirtide in patients chronically infected with HBV and hepatitis D virus.

METHODS

MYR202 (ClinicalTrials.gov, NCT03546621; EudraCT, 2016-000395-13) was a multicentre, parallel-group, randomised, open-label, phase 2 trial. Adults (aged 18-65 years) with chronic hepatitis D virus infection, including patients with cirrhosis and patients who had contraindications to PegIFNα treatment or for whom treatment did not work, were eligible and were enrolled from four hospitals in Germany and 12 hospitals in Russia. Patients were randomly assigned (1:1:1:1) to receive 2 mg (n=28), 5 mg (n=32), or 10 mg (n=30) subcutaneous bulevirtide once per day with tenofovir disoproxil fumarate (TDF; 245 mg once per day orally) or TDF alone (245 mg once per day orally; n=30) for 24 weeks. Randomisation was done using a digital block scheme with stratification, consisting of 480 randomisation numbers separated into 30 blocks. The primary endpoint was undetectable hepatitis D virus RNA or 2 log10 IU/mL or higher decline in hepatitis D virus RNA at week 24, which was analysed in the modified intention-to-treat population, including patients who received study medication at least once after randomisation. Hepatitis D virus RNA concentrations were monitored until week 48. Safety was assessed for all patients who received at least one dose of bulevirtide or TDF.

FINDINGS

Between Feb 16, 2016, and Dec 8, 2016, 171 patients with chronic hepatitis D virus infection were screened; 51 were ineligible based on the exclusion criteria and 120 patients (59 with cirrhosis) were enrolled. At week 24, 15 (54%, 95% CI 34-73) of 28 patients achieved undetectable hepatitis D virus RNA or a 2 log10 IU/mL or more decline in hepatitis D virus RNA (p<0·0001 vs TDF alone) with 2 mg bulevirtide, 16 (50%, 32-68) of 32 with 5 mg bulevirtide (p<0·0001), and 23 (77%, 58-90) of 30 with 10 mg bulevirtide (p<0·0001), versus one (4%, 0·1-18) of 28 with TDF alone. By week 48 (24 weeks after bulevirtide cessation), hepatitis D virus RNA concentrations had rebounded, with median changes from week 24 to week 48 of 1·923 log10 IU/mL (IQR 0·566-2·485) with 2 mg bulevirtide, 1·732 log10 (0·469-2·568) with 5 mg bulevirtide, and 2·030 log10 (1·262-2·903) with 10 mg bulevirtide. There were no deaths associated with treatment. Three (9%) patients in the bulevirtide 5 mg group, two (7%) patients in the bulevirtide 10 mg group, and one (4%) patient in the TDF group had serious adverse events. Common treatment-emergent adverse events included asymptomatic bile salt increases and increases in alanine aminotransferase and aspartate aminotransferase.

INTERPRETATION

Bulevirtide induced a significant decline in hepatitis D virus RNA over 24 weeks. After cessation of bulevirtide, hepatitis D virus RNA concentrations rebounded. Longer treatment durations and combination therapies should be investigated.

FUNDING

Hepatera LLC, MYR GmbH, and the German Centre for Infection Research, TTU Hepatitis.

HIOPP-6 – a pilot study on the evaluation of an electronic tool to assess and reduce the complexity of drug treatment considering patients’ views

Background

A complex drug treatment might pose a barrier to safe and reliable drug administration for patients. Therefore, a novel tool automatically analyzes structured medication data for factors possibly contributing to complexity and subsequently personalizes the results by evaluating the relevance of each identified factor for the patient by means of key questions. Hence, tailor-made optimization measures can be proposed.

Methods

In this controlled, prospective, exploratory trial the tool was evaluated with nine general practitioners (GP) in three study groups: In the two intervention groups the tool was applied in a version with (G_{I_with}) and a version without (G_{I_without}) integrated key questions for the personalization of the analysis, while the control group (G_C) did not use any tools (routine care). Four to eight weeks after application of the tool, the benefits of the optimization measures to reduce or mitigate complexity of drug treatment were evaluated from the patient perspective.

Results

A total of 126 patients regularly using more than five drugs could be included for analysis. GP suggested 117 optimization measures in G_{I_with}, 83 in G_{I_without}, and 2 in G_C. Patients in G_{I_with} were more likely to rate an optimization measure as helpful than patients in G_{I_without} (IRR: 3.5; 95% CI: 1.2—10.3). Thereby, the number of optimization measures recommended by the GP had no significant influence (P = 0.167).

Conclusions

The study suggests that an automated analysis considering patient perspectives results in more helpful optimization measures than an automated analysis alone – a result which should be further assessed in confirmatory studies.

Trial registration

The trial was registered retrospectively at the German Clinical Trials register under DRKS-ID DRKS00025257 (17/05/2021).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01757-0.

Molecular prediction of clinical response to anti‐PD ‐1/ anti‐PD‐L1 immune checkpoint inhibitors: new perspectives for precision medicine and mass spectrometry‐based investigations

Monoclonal antibodies (mAbs) acting as immune checkpoint inhibitors (ICIs) are among the most frequently used immunotherapies in oncology. However, precision medicine approaches to adapt the treatment to the patient are still poorly exploited. Given the risk of severe adverse reactions, predicting patient eligibility for ICI therapy represents a great asset for precision medicine. Today, the extended panel of mass spectrometric approaches, accompanied by newly developed sample preparation methods is a strategy of choice for responder and non-responder stratification on a molecular basis, and early detection of resistance. In this perspective article, we review the biodisposition of mAbs, the interest in molecular stratification of patients treated with these mAbs, and the possible analytical strategies to achieve this goal, with a major emphasis on mass spectrometric approaches.

Oral bioavailability of microdoses and therapeutic doses of midazolam as a 2-dimensionally printed orodispersible film in healthy volunteers

PURPOSE

The use of two-dimensional (2D) printing technologies of drugs on orodispersible films (ODF) can promote dose individualization and facilitate drug delivery in vulnerable patients, including children. We investigated midazolam pharmacokinetics after the administration of 2D-printed ODF.

METHODS

Midazolam doses of 0.03 and 3 mg were printed on an ODF using a 2D drug printer. We investigated the bioavailability of the two midazolam doses with ODF swallowed immediately (ODF-IS) or delayed after 2 min (ODF-DS) by comparing their pharmacokinetics with intravenous and oral midazolam solution in 12 healthy volunteers.

RESULTS

The relative bioavailability of ODF-IS 0.03 mg was 102% (90% confidence interval: 89.4-116) compared to oral solution and for 3 mg 101% (86.8-116). C_max of ODF-IS 0.03 mg was 95.5% (83.2-110) compared to oral solution and 94.3% (78.2-114) after 3 mg. Absolute bioavailability of ODF-IS 0.03 mg was 24.9% (21.2-29.2) and for 3 mg 28.1% (23.4-33.8) (oral solution: 0.03 mg: 24.4% (22.0-27.1); 3 mg: 28.0% (25.0-31.2)). Absolute bioavailability of ODF-DS was significantly larger than for ODF-IS (0.03 mg: 61.4%; 3 mg: 44.1%; both p < 0.0001).

CONCLUSION

This trial demonstrates the tolerability and unchanged bioavailability of midazolam printed on ODF over a 100-fold dose range, proving the suitability of ODF for dose individualization. Midazolam ODF-IS AUC_0-∞ in both doses was bioequivalent to the administration of an oral solution. However, C_max of the therapeutic dose of ODF-IS missed bioequivalence by a clinically not relevant extent. Prolonged mucosal exposure increased bioavailability. (Trial Registration EudraCT: 2020-003984-24, August 10, 2020).

Comparison of the antiarrhythmic potential of doxapram and its metabolite ketodoxaparam

Background

A few years ago, the TASK-1 channel has been established as a potential new target for the therapy of atrial fibrillation (AF). In the heart, TASK-1 is almost exclusively expressed in the atria and is significantly upregulated in AF patients. Therefore, it plays an important role in the shortening of the atrial action potential observed during AF, making TASK-1 a promising target for AF therapy. This could be proven in a porcine model of persistent AF in which an intravenous application of the TASK-1 inhibitor doxapram led to a termination of AF and the restoration of sinus rhythm (SR). Doxapram's metabolite ketodoxapam is described in the literature as being active with limited data available on its usage. Therefore, the effect of ketodoxapram on TASK-1 and its possible use in AF therapy still needs to be investigated.

Purpose

The purpose of the present study was to assess the potential of ketodoxapram in the termination of AF. Furthermore, a comparison between doxapram and ketodoxapram was performed based on electrophysiological and pharmacological data.

Methods

UPLC-MS/MS assays were developed and validated for the measurement of doxapram and ketodoxapram in porcine plasma and brain tissue. Using these assays, the pharmacokinetics of both substances, after intravenous injections of 1 mg/kg, were determined in pigs. Furthermore, brain and plasma concentrations were measured to assess brain-to-plasma ratios. A porcine AF model was used to estimate the antiarrhythmic potential. Electrophysiological properties were evaluated, using two-electrode voltage clamp experiment on Xenopus laevis oocytes which heterologously expressed atrial potassium channels, to calculate the effect of doxapram and ketodoxapram on channel function. Furthermore, whole-cell patch clamp measurements were performed on isolated human cardiomyocytes.

Results

Doxapram and ketodoxapram showed strong inhibitory effects on TASK-1 (IC50 1.0 μM and 0.8 μM) and TASK-3 (5.9 μM and 1.5 μM), but no significant effect on the other measured ion channels. The maximal inhibition on TASK-1 was 96%. The brain-to-plasma ratio for doxapram (0.58) was almost ten-fold higher than for ketodoxapram (0.065), hinting at a reduced crossing of the blood-brain barrier (BBB) for ketodoxapram. The terminal half-life (t1/2) of ketodoxapram (1.71 h) was longer and the maximal concentration (Cmax; 4,604 ng/ml) was higher than for doxapram (1.38 h; 1,780 ng/ml). In a porcine model of AF, ketodoxapram led to a significantly reduced AF burdens comparable to doxapram.

Conclusions

Doxapram and ketodoxapram both show strong inhibitory effects on TASK-1, making them good candidates for a TASK-1 based AF therapy. Ketodoxapram with its longer t1/2, reduced crossing of the BBB and higher Cmax points towards a possible superiority in the treatment of AF compared to doxapram. Studies in a porcine AF model showed promising results for the use of doxapram and ketodoxapram in AF therapy.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): German Research Foundation

A prediction model for nonpersistence or nonadherence to direct oral anticoagulants in hospitalized patients with atrial fibrillation

BACKGROUND: Medication adherence and persistence is fundamental for drug effectiveness, which is also true for the prevention of strokes in patients with atrial fibrillation (AF). Adherence to direct oral anticoagulants (DOACs) as first-line agents is often high in the early posthospital period. However, adherence often sharply declines (or eventually leads to nonpersistence) in the post-discharge ambulatory period, rendering stroke prevention ineffective. If patients at high risk of nonpersistence or nonadherence could be identified early, they could be offered early intervention measures to improve adherence and/or persistence. OBJECTIVE: To develop and internally validate a predictive model for medication nonadherence and nonpersistence to DOAC treatment in patients with AF after discharge using health insurance claims data. METHODS: We selected health insurance claims data between 2011 and 2016 from 8,055 patients with AF who were newly treated with rivaroxaban or apixaban after a hospital admission for stroke, transient ischemic attack, or AF. In the post-discharge ambulatory period, medication adherence was derived as the proportion of days covered, calculated from drug dispensation data. A maximum permissible 90-day gap between the end of a prescription and the next dispensation was used to estimate persistence. Candidate predictors were either derived from the index hospital admission or summarized from the previous year (eg, comorbidities or medication adherence to long-term treatments, such as ß-blockers, renin-angiotensin system inhibitors, statins, and thyroid hormones). A regularized logistic regression model was fitted using the least absolute shrinkage and selection operator in a split-sample approach (66.7% training data; 33.3% test data) to predict a composite of medication nonadherence/nonpersistence. Discrimination performance was assessed using the area under the receiver operating characteristic curve, the maximum sensitivity/specificity, and the scaled Brier score. A calibration curve fitted by linear regression was used to evaluate model calibration. RESULTS: The average age of the study participants was 79.7 years, 62% were female, and 3,515 patients (44%) were adherent and persistent (median follow-up of 185 days). Medication adherence to previous long-term treatments showed strong predictive properties. The developed model discriminated well (concordance statistic: 0.755), was well calibrated, and showed a scaled Brier score of 0.202 for identification of patients at risk. CONCLUSIONS: The model successfully predicted medication non-adherence/nonpersistence to DOAC treatment after discharge. Such a model could help ensure that targeted interventions are already in place at the time of hospital discharge, potentially preventing strokes and reducing costs. DISCLOSURES: Mr Wirbka is funded by the German Innovation Funds according to § 92a (2) Volume V of the Social Insurance Code (§ 92a Abs. 2, SGBV-Fünftes Buch Sozialgesetzbuch), grant number: 01VSF18019. Dr Haefeli received financial support from Daiichi-Sankyo, app development (https://www.easydoac.de/), and Bayer. He also received personal speaker fees from Bristol Myers-Squibb and Daiichi-Sankyo Online Seminar. Dr Meid is funded by the Physician-Scientist Programme of the Medical Faculty of Heidelberg University.

First-in-human, randomized, double-blind, placebo-controlled, dose escalation trial of the anti-herpes simplex virus monoclonal antibody HDIT101 in healthy volunteers

HDIT101 is a first-in-class humanized monoclonal antibody recognizing a conserved epitope in glycoprotein B, a target present on the surface of herpes simplex virus 1 (HSV-1) and HSV-2 particles as well as on virus-infected cells. This was a first-in-human, single-center, double-blind, placebo-controlled trial in 24 healthy volunteers, randomized 3:1 (placebo:active) in each of the six dose levels with escalating doses up to 12,150 mg HDIT101. HDIT101 was administered intravenously, to study safety, pharmacokinetics (PKs), and immunogenicity. HDIT101 was well-tolerated in all recipients and no serious or severe adverse events, no infusion-related reactions, and no events suggestive of dose limiting off-target toxicity occurred. The mean serum exposure (area under the curve from zero to infinity [AUC_0-∞ ]) of HDIT101 showed a linear increase from 4340 h*μg/ml at a dose of 50 mg to 1,122,247 h*μg/ml at a dose of 12,150 mg. No immunogenic effects following HDIT101 exposure were observed at any of the applied doses. HDIT101 demonstrated the expected PK properties of a monoclonal antibody was well-tolerated, and could be safely administered even at excessively high doses that may be required for treatment of patients with septical HSV spread.

Task sharing in an interprofessional medication management program - a survey of general practitioners and community pharmacists

Background

Pharmacist-led medication review and medication management programs (MMP) are well-known strategies to improve medication safety and effectiveness. If performed interprofessionally, outcomes might even improve. However, little is known about task sharing in interprofessional MMP, in which general practitioners (GPs) and community pharmacists (CPs) collaboratively perform medication reviews and continuously follow-up on patients with designated medical and pharmaceutical tasks, respectively. In 2016, ARMIN (Arzneimittelinitiative Sachsen-Thüringen) an interprofessional MMP was launched in two German federal states, Saxony and Thuringia. The aim of this study was to understand how GPs and CPs share tasks in MMP when reviewing the patients’ medication.

Methods

This was a cross-sectional postal survey among GPs and CPs who participated in the MMP. Participants were asked who completed which MMP tasks, e.g., checking drug-drug interactions, dosing, and side effects. In total, 15 MMP tasks were surveyed using a 5-point Likert scale ranging from “I complete this task alone” to “GP/CP completes this task alone”. The study was conducted between 11/2020 and 04/2021. Data was analyzed using descriptive statistics.

Results

In total, 114/165 (69.1%) GPs and 166/243 (68.3%) CPs returned a questionnaire. The majority of GPs and CPs reported (i) checking clinical parameters and medication overuse and underuse to be completed by GPs, (ii) checking storage conditions of drugs and initial compilation of the patient’s medication including brown bag review being mostly performed by CPs, and (iii) checking side-effects, non-adherence, and continuous updating of the medication list were carried out jointly. The responses differed most for problems with self-medication and adding and removing over-the-counter medicines from the medication list. In addition, the responses revealed that some MMP tasks were not sufficiently performed by either GPs or CPs.

Conclusions

Both GPs’ and CPs’ expertise are needed to perform MMP as comprehensively as possible. Future studies should explore how GPs and CPs can complement each other in MMP most efficiently.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08378-4.

Shortcomings of Administrative Data to Derive Preventive Strategies for Inhospital Drug-Induced Acute Kidney Failure—Insights from Patient Record Analysis

Structured analyses of hospital administrative data may detect potentially preventable adverse drug events (ADE) and therefore are considered promising sources to prevent future harm and estimate cost savings. Whether results of these analyses indeed correspond to ADE that may be preventable in clinical routines needs to be verified. We exemplarily screened all adult inpatients admitted to a German University Hospital (n = 54,032) for International Classification of Diseases-10th revision (ICD-10) diagnoses coding for drug-induced kidney injury (AKI). In a retrospective chart review, we checked the coded adverse events (AE) for inhospital occurrence, causality to drug exposure, and preventability in all identified cases and calculated positive predictive values (ppv). We identified 69 inpatient cases of whom 41 cases (59.4%) experienced the AE in the hospital (ppv-range 0.43–0.80). Causality assessment revealed a rather likely causal relationship between AE and drug exposure in 11 cases (15.9, 11/69, ppv-range 0.17–0.22) whereby preventability measures could be postulated for seven cases (10.1%, 7/69). Focusing on drug-induced AKI, this study exemplarily underlines that ICD-10-code-based ADE prevention efforts are quite limited due to the small identification rate and its high proportion of primarily outpatient events. Furthermore, causality assessment revealed that cases are often too complex to benefit from generic prevention strategies. Thus, ICD-10-code-based calculations might overestimate patient harm and economic losses.

Prevalence and patient-rated relevance of complexity factors in medication regimens of community-dwelling patients with polypharmacy

Purpose

To describe the prevalence of complexity factors in the medication regimens of community-dwelling patients with more than five drugs and to evaluate the relevance of these factors for individual patients.

Methods

Data were derived from the HIOPP-6 trial, a controlled study conducted in 9 general practices which evaluated an electronic tool to detect and reduce complexity of drug treatment. The prevalence of complexity factors was based on the results of the automated analysis of 139 patients’ medication data. The relevance assessment was based on the patients’ rating of each factor in an interview (48 patients included for analysis).

Results

A median of 5 (range 0–21) complexity factors per medication regimen were detected and at least one factor was observed in 131 of 139 patients. Almost half of these patients found no complexity factor in their medication regimen relevant.

Conclusion

In most medication regimens, complexity factors could be identified automatically, yet less than 15% of factors were indeed relevant for patients as judged by themselves. When assessing complexity of medication regimens, one should especially consider factors that are both particularly frequent and often challenging for patients, such as use of inhalers or tablet splitting.

Trial registration

The HIOPP-6 trial was registered retrospectively on May 17, 2021, in the German Clinical Trials register under DRKS-ID DRKS00025257.

Supplementary information

The online version contains supplementary material available at 10.1007/s00228-022-03314-1.

Foerster K, Terstegen T, Vogt C, Said A, Schulz M, E. Haefeli W. Oral Drugs Against COVID-19

BACKGROUND

Five-day oral therapies against early COVID-19 infection have recently been conditionally approved in Europe. In the drug combination nirmatrelvir + ritonavir (nirmatrelvir/r), the active agent, nirmatrelvir, is made bioavailable in clinically adequate amounts by the additional administration of a potent inhibitor of its first-pass metabolism by way of cytochrome P450 [CYP] 3A in the gut and liver. In view of the central role of CYP3A in the clearance of many different kinds of drugs, and the fact that many patients with COVID-19 are taking multiple drugs to treat other conditions, it is important to assess the potential for drug interactions when nirmatrelvir/r is given, and to minimize the risks associated with such interactions.

METHODS

We defined the interaction profile of ritonavir on the basis of information derived from two databases (Medline, GoogleScholar), three standard electronic texts on drug interactions, and manufacturer-supplied drug information. We compiled a list of drugs and their potentially relevant interactions, developed a risk min - imization algorithm, and applied it to the substances in question. We also compiled a list of commonly prescribed drugs for which there is no risk of interaction with nirmatrelvir/r.

RESULTS

Out of 190 drugs and drug combinations, 57 do not need any special measures when given in combination with brief, low-dose ritonavir treatment, while 15 require dose modification or a therapeutic alternative, 8 can be temporarily discontinued, 9 contraindicate ritonavir use, and 102 should preferably be combined with a different treatment.

CONCLUSION

We have proposed measures that are simple to carry out for the main types of drug that can interact with ritonavir. These measures can be implemented under quarantine conditions before starting a 5-day treatment with nirmatrelvir/r.

Drug Treatment of Hypercholesterolemia in Older Adults: Focus on Newer Agents

There is increasing research interest in cholesterol-lowering therapy in older patients. The newer lipid-lowering agents (the proprotein convertase subtilisin/kexin type 9 [PCSK9] inhibitors evolocumab and alirocumab; the PCSK9 synthesis inhibitor inclisiran, and the adenosine triphosphate–citrate lyase inhibitor bempedoic acid) might also provide more options for the future treatment of older patients. Data analyses of the phase III outcome trials of the PCSK9 inhibitors suggest that their clinical benefits are maintained at older ages and that there is no increased relative risk of adverse events in older patients; however, data from patients aged ≥ 75 years and particularly aged ≥ 85 years are limited, and the trials did not collect information on the frailty status of patients. Frailty is a predictor of adverse outcomes, including mortality, and might help guide therapy decisions. To date, no outcome data are available for cardiovascular endpoints for the low-density lipoprotein cholesterol-lowering drugs inclisiran and bempedoic acid. Except for the risk of gout and tendon rupture with bempedoic acid, which remains to be further characterized in larger populations, the safety profile of the novel lipid-lowering agents in older patients seems favorable. The newer lipid-lowering agents could be added to other lipid-lowering medication or used as an alternative treatment in older patients with documented statin intolerance (as is already recommended in guidelines for the PCSK9 inhibitors), such as myopathy. Especially in older patients needing high-intensity therapy despite polypharmacy or certain comedications, the absence of clinically relevant drug–drug interactions with the PCSK9 inhibitors and inclisiran might be an advantage.

Functional Characterization of the Solute Carrier LAT-1 (SLC7A5/SLC2A3) in Human Brain Capillary Endothelial Cells with Rapid UPLC-MS/MS Quantification of Intracellular Isotopically Labelled L-Leucine

The solute carrier L-type amino acid transporter 1 (LAT-1/SLC7A5) is a viable target for drug delivery to the central nervous system (CNS) and tumors due to its high abundance at the blood-brain barrier and in tumor tissue. LAT-1 is only localized on the cell surface as a heterodimer with CD98, which is not required for transporter function. To support future CNS drug-delivery development based on LAT-1 targeting, we established an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) assay for stable isotopically labeled leucine ([¹³C₆, ¹⁵N]-L-leucine), with a dynamic range of 0.1-1000 ng/mL that can be applied for the functional testing of LAT-1 activity when combined with specific inhibitors and, consequently, the LAT-1 inhibition capacity of new compounds. The assay was established in a 96-well format, facilitating high-throughput experiments, and, hence, can support the screening for novel inhibitors. Applicable recommendations of the US Food and Drug Administration and European Medicines Agency for bioanalytical method validation were followed to validate the assay. The assay was applied to investigate the IC₅₀ of two well-known LAT-1 inhibitors on hCMEC/D3 cells: the highly specific LAT-1 inhibitor JPH203, which was also used to demonstrate LAT-1 specific uptake, and the general system L inhibitor BCH. In addition, the [¹³C₆, ¹⁵N]-L-leucine uptake was determined on two human brain capillary endothelial cell lines (NKIM-6 and hCMEC/D3), which were characterized for their expressional differences of LAT-1 at the protein and mRNA level and the surface amount of CD98. The IC₅₀ values of the inhibitors were in concordance with previously reported values. Furthermore, the [¹³C₆, ¹⁵N]-L-leucine uptake was significantly higher in hCMEC/D3 cells compared to NKIM-6 cells, which correlated with higher expression of LAT-1 and a higher surface amount of CD98. Therefore, the UPLC-MS/MS quantification of ([¹³C₆, ¹⁵N]-L-leucine is a feasible strategy for the functional characterization of LAT-1 activity in cells or tissue.