Dose Reduction Criteria Research Articles

Plasma apixaban levels and thrombin generation assay in patients with atrial fibrillation with dose reduction criteria of apixaban

Abstract Background Off-label reduced-dose apixaban is commonly prescribed in patients with atrial fibrillation (AF). However, the pharmacokinetic data of apixaban according to the dosage and label is limited especially in those with dose reduction criteria of apixaban. Purpose We investigated the apixaban plasma concentration (PC) and thrombin generation assay (TGA) parameters across different apixaban dose settings. Methods We enrolled 398 non-valvular AF patients with more than single-dose reduction criteria of apixaban and divided them into three groups: (1) on-label standard dose (single dose-reduction criterion with standard-dose of apixaban 5mg twice daily, n=173); (2) off-label reduced-dose (single dose-reduction criterion with apixaban 2.5mg twice daily, n=61); and (3) on-label reduced-dose (two or more dose-reduction criteria with apixaban 2.5mg twice daily, n=164). Apixaban PC by anti-Xa assay and TGA parameters of these three groups were compared at the trough level. Results The on-label standard dose group showed a higher PC than the on-label reduced dose (124.7 vs. 80.3 ng/mL, p<0.001), and the on-label reduced dose exhibited a higher PC than the off-label reduced dose (80.3 vs. 53.2 ng/mL, p=0.031) (Figure). The TGA parameters displayed a similar pattern of differences, with the on-label standard dose group tends to show the least thrombogenic profiles (Figure). Lower creatinine clearance (CrCl), older age, and female sex were statistically significant predictors for a higher apixaban PC by multivariable regression model (p<0.001, p=0.043, and 0.023, respectively), and CrCl was the most influential variable to dichotomize apixaban PC in all three groups (Figure). Conclusions Off-label reduced-dose apixaban group exhibited significantly lower apixaban level than both on-label standard dose and on-label reduced-dose apixaban groups, suggesting the importance of adhering to current dose-reduction criteria for maintaining appropriate apixaban levels. Caution is particularly advised in off-label under-dosing for patients with high creatinine clearance. Further investigation into the impact of off-label under-dosing on clinical outcomes is essential to guide optimal therapeutic strategies.

Efficacy and safety of long-term edoxaban treatment for low body weight cancer patients with isolated distal deep vein thrombosis: a post-hoc subgroup analysis of the ONCO DVT study

Abstract Background Low body weight is known to be a bleeding risk in the anticoagulation treatment. ONCO DVT study revealed that 12-month edoxaban treatment for cancer patients with isolated distal deep vein thrombosis (DVT) reduced a composite outcome of a symptomatic recurrent venous thromboembolism (VTE) or VTE-related death compared with 3-month edoxaban treatment. However, the efficacy and safety of long-term edoxaban treatment for cancer patients with low body weight is unclear. Purpose In this subgroup analysis, we assessed the efficacy and safety of 12-month edoxaban treatment for low body weight cancer patients with isolated distal DVT. Methods We conducted a post-hoc subgroup analysis of the ONCO DVT study in the low body weight patients. ONCO DVT study was a multicenter, open-label, adjudicator-blinded, randomized clinical trial. Cancer patients with isolated distal DVT were assigned to 12-month or 3-month edoxaban treatment. The primary endpoint was a composite outcome of a symptomatic recurrent VTE or VTE-related death at 12 months. The major secondary endpoint was major bleeding at 12 months. We enrolled patients who met low body weight defined in Japanese Version of High Bleeding Risk criteria (<55 kg for men, <50 kg for women) and evaluated the efficacy and safety of 12-month edoxaban treatment using logistic regression models and log-rank test. Results Among 601 patients in the intention-to-treat population of ONCO DVT study, 322 patients (53.6%) met low body weight: 151 patients were in 12-month edoxaban group and 171 patients were in 3-month edoxaban group. The body weight was similar between two group (47.1±5.2 kg in 12-month edoxaban group vs. 46.9±5.4 kg in 3-month edoxaban group; P=0.77). All of them used a lower dose edoxaban (30 mg once daily) following the dose reduction criteria. 12-month edoxaban group had lower rates of the primary endpoint compared with 3-month edoxaban group (2 patients (1.3%) vs. 10 patients (5.8%); Odds ratio 0.22 [95% CI, 0.05–1.00]; Log-rank P=0.036). There was no significant difference in the major secondary endpoint of major bleeding (12 patients (7.9%) in 12-month edoxaban group vs. 16 patients (9.4%) in 3-month edoxaban group; Odds ratio 0.83 [95% CI, 0.38–1.83]; Log-rank P=0.65). All clinically relevant bleeding events occurred in 22 patients (14.6%) in 12-month edoxaban group and in 27 patients (15.8%) in 3-month edoxaban group (Odds ratio 1.40 [0.90–2.19]; Log rank P=0.13), resulting in the comparable risk of bleeding in the 12-month edoxaban group. Conclusions Our study suggests that 12-month edoxaban treatment for low body weight cancer patients with isolated distal DVT prevents recurrent VTE or VTE-related death without increasing the risk of bleeding compared to 3-month edoxaban treatment.primary endpointsecondary endpoint

Analyzing the economic ramifications of the broad implementation of generic prasugrel

Abstract Introduction The 2023 European Acute Coronary Syndrome (ACS) guidelines state that prasugrel (PRG) should be considered in preference to ticagrelor (TCG) in patients (pts) who proceed to percutaneous coronary angioplasty (PCI). In Portugal, PRG is less available due to earlier evidence considering pretreatment and contraindications for each drug. PRG (10mg) is currently a generic drug, while TCG is not. We aimed to evaluate the proportion of pts that could be switched from TCG to PRG, and the economic impact of a widespread national adoption. Methods To determine eligibility for generic PRG 10mg, we examined a single center prospective database of consecutive ACS pts undergoing PCI in a full year. Eligibility for TCG and PRG was based on drug specific contraindications, previous stroke for PRG and chronic liver disease (CLD) for TCG, and indication for PRG dose reduction (≤60 kg and ≥75 years). To estimate hospital costs we used the price per pill indicated by the pharmacy (0.98€ TCG, 0.67€ PRG). To obtain post-discharge and NHS savings we used the INFARMED public information. We estimated 3500 PCIs per year on a national level, based on published data. Results A total of 780 pts were included, median age 68±10.4years, 523 (67.1%) were male, 51.9% (n=406) had non-ST elevation ACS. Mean admission time was 8.36 days. Considering PRG and TCG contraindications, 157 pts (20.3%) had a previous history of stroke and 20pts (2.6%) had CLD. 150 pts (19.2%) had PRG dose reduction criteria. Eligible for PRG 10mg and TCG 90mg were 434 pts (57.8% of total PCI pts). Cost per admission would be 33 697.35€ for TCG and 17 617.28€ for PRG. At a national level, hospital costs can be reduced by 16080.07€. Considering the 1-year outpatient setting and a widespread generic PRG 10mg adoption, NHS savings are estimated in 898 323.59€, and patient savings in 401248.25€ (198.38€ per patient). Conclusions ACS pts in real-world scenarios exhibit both eligibility for PRG and TCG. Considering the lower cost, the NHS can potentially save 914 403,66€ (figure 1) annually through the widespread adoption of generic PRG 10mg.

Optimal long-term anticoagulation after acute pulmonary embolism: current state of the art and a look into the near future.

This review aims to summarize the current state of the art and future directions in optimal long-term anticoagulation following acute pulmonary embolism (PE). Actual studies and guidelines underscore the preference for direct oral anticoagulants (DOAC) in standard therapeutic doses for maintenance therapy post-PE, while considering patient-specific factors and dose-reduction criteria. Risk stratification should always include the assessment of concomitant trigger- or risk factors regarding their strength and persistence. The use of tools like specific scores can facilitate the identification of optimal candidates for long-term therapy, emphasizing once more personalized approaches and strategies. Special patient groups, such as cancer associated thrombosis, chronic thromboembolic pulmonary hypertension or antiphospholipid syndrome require even more tailored therapy approaches. Optimal long-term anticoagulation post-PE should be guided by straightforward and individual risk assessment strategies. The array of indications for DOACs has gotten wider in last years, also within special patient groups. Still, chronic thromboembolic pulmonary hypertension and antiphospholipid syndrome remains domain of vitamin K agonists.

Plasma apixaban concentrations and thrombin generation assay parameters in response to dose reduction for atrial fibrillation.

To investigate plasma apixaban concentrations and thrombin generation assay (TGA) parameters across different apixaban doses in atrial fibrillation patients who had dose-reduction criteria for apixaban. This observational study included 374 patients (mean age 75.6 ± 7.7 years, 54.8% female) with dose-reduction criteria for apixaban. The patients were divided into 3 groups: (i) on-label standard dose (5 mg twice daily, n =166); (ii) on-label reduced dose (2.5 mg twice daily, n =55); and (iii) off-label underdose (2.5 mg twice daily, n =153). Apixaban concentrations determined via the anti-Xa assay and TGA parameters were compared at trough levels. The off-label underdose group exhibited significantly lower apixaban trough concentrations than the on-label reduced-dose and standard-dose groups (56.7 ± 42.9 vs. 83.7 ± 70.4 vs. 129.9 ± 101.8 ng/mL, all P <.001). Less than 70% of all patients fell within the expected range of apixaban concentrations. Proportions exceeding the upper limit of the expected range were significantly lower in the off-label underdose group (1.3%) than in the on-label reduced-dose (9.1%, P =.005) and standard-dose (12.7%, P <.001) groups. The TGA parameters showed the on-label standard-dose group displaying the lowest thrombogenic profiles. Lower creatinine clearance was the most significant predictor of higher apixaban concentrations. Off-label underdosed apixaban resulted in lower apixaban concentrations than both on-label standard and reduced-dose regimens. A considerable proportion of the patients exhibited apixaban concentrations outside the expected range, suggesting the potential benefits of plasma concentration monitoring. Further studies are needed to compare dosages directly, investigate the impact of plasma apixaban concentration monitoring and validate the current dose-reduction criteria.

Dose Reduction of Edoxaban in Patients 80 Years and Older With Atrial Fibrillation

In older patients with atrial fibrillation who take anticoagulants for stroke prevention, bleeding is increased compared with younger patients, thus, clinicians frequently prescribe lower than recommended doses in older patients despite limited randomized data. To evaluate ischemic and bleeding outcomes in patients 80 years and older with atrial fibrillation receiving edoxaban, 60 mg vs 30 mg, and edoxaban, 30 mg vs warfarin. The ENGAGE AF-TIMI 48 trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48) was a parallel-design, double-blind, global clinical trial that randomized patients with atrial fibrillation to either one of 2 edoxaban dosing regimens or warfarin. This secondary analysis focused on patients 80 years or older without dose-reduction criteria receiving edoxaban, 60 mg vs 30 mg, as well as patients with or without dose-reduction criteria receiving edoxaban, 30 mg, vs warfarin. Study data were analyzed between October 2022 and December 2023. Oral edoxaban, 30 mg once daily; edoxaban, 60 mg once daily; or warfarin. Primary net clinical outcome of death, stroke or systemic embolism, and major bleeding and each individual component. The current analysis included 2966 patients 80 years and older (mean [SD] age, 83 [2.7] years; 1671 male [56%]). Among 1138 patients 80 years and older without dose-reduction criteria, those receiving edoxaban, 60 mg vs 30 mg, had more major bleeding events (hazard ratio [HR], 1.57; 95% CI, 1.04-2.38; P = .03), particularly gastrointestinal hemorrhage (HR, 2.24; 95% CI, 1.29-3.90; P = .004), with no significant difference in efficacy end points. Findings were supported by analyses of endogenous factor Xa inhibition, a marker of anticoagulant effect, which was comparable between younger patients receiving edoxaban, 60 mg, and older patients receiving edoxaban, 30 mg. In 2406 patients 80 years and older with or without dose-reduction criteria, patients receiving edoxaban, 30 mg, vs warfarin had lower rates of the primary net clinical outcome (HR, 0.78; 95% CI, 0.68-0.91; P = .001), major bleeding (HR, 0.59; 95% CI, 0.45-0.77; P < .001), and death (HR, 0.83; 95% CI, 0.70-1.00; P = .046), whereas rates of stroke or systemic embolism were comparable. In this post hoc analysis of the ENGAGE AF-TIMI 48 randomized clinical trial, in patients 80 years and older with atrial fibrillation, major bleeding events were lower in patients randomized to receive edoxaban, 30 mg per day, compared with either edoxaban, 60 mg per day (in patients without dose-reduction criteria), or warfarin (irrespective of dose-reduction status), without an offsetting increase in ischemic events. These data support the concept that lower-dose anticoagulants, such as edoxaban, 30 mg, may be considered in older patients with atrial fibrillation even in the absence of dose-reduction criteria. ClinicalTrials.gov Identifier: NCT00781391.

Off-Label Reduced Dose Apixaban in Older Adults With Atrial Fibrillation and Associated Outcomes.

Apixaban is commonly used to prevent stroke in older adults with nonvalvular atrial fibrillation (AF). Although its package insert has specific dose reduction criteria, providers may dose reduce outside of these parameters based on clinical scenarios. The primary objective was to determine the incidence of apixaban off-label reduced dosing, while secondarily determining the safety and efficacy outcomes associated with such dosing. A retrospective analysis of patients aged 65 and older with orders for apixaban for AF was institutional review board (IRB)-approved and conducted across 3 academic medical centers. Patients receiving off-label reduced-dose apixaban (ie, "underdosed") were matched to a cohort of patients dosed according to the package insert at the standard dosing (5 mg twice daily) using stratified random sampling. Secondary outcomes included 1-year incidence of major bleeding, clinically relevant non-major bleeding (CRNMB), stroke or transient ischemic attack (TIA), and mortality. The Fisher exact tests were used to compare between-group differences. Of the 1172 patients meeting initial inclusion criteria, 201 (17%) were dosed off-label, with 175 (15%) "underdosed." The 147 "underdosed" patients with documented follow-up were matched with 139 patients receiving standard Food and Drug Administration (FDA)-labeled dosing. There were no significant differences in incidence of stroke (2.7% vs 2.2%), major bleeding (0% vs 0.7%), and CRNMB (2.7% vs 1.4%) in the off-label reduced dosing versus standard dosing groups. All-cause mortality was higher in the off-label reduced-dose group (16 [10.9%] vs 2 [1.4%], P < 0.05). Older adults with nonvalvular AF are commonly prescribed lower-than-recommended doses of apixaban. However, no significant association was found between empiric off-label reduced dosing and stroke or bleeding outcomes.

Impact of different dose reduction criteria on dose assignment of current DOACs and related outcomes: an analysis from 4-year data of the ETNA-AF Europe programme

Abstract Background Direct oral anticoagulants (DOACs) are the standard treatment for stroke prevention in patients with atrial fibrillation (AF). Pharmacological characteristics and dose reduction criteria of the four currently available DOACs are different. Several studies have reported frequent use of non-recommended doses of DOACs associated with worse clinical outcomes. Data from real-world studies, such as the edoxaban Treatment in routiNe clinical prActice (ETNA)-AF, may help assessing the size of this phenomenon and its impact on clinical outcomes. Purpose To evaluate the distribution of dose reduction criteria and explore associated outcomes in a large, unselected, real-world population using 4-year data from the ETNA-AF EU study. Methods The ETNA-AF EU is a prospective, observational, study to evaluate safety and effectiveness of edoxaban in patients with AF from Europe. Patients with available data regarding the SmPC dose reduction criteria of the four currently available DOACs were included. Patients with a creatinine clearance &amp;lt;30 mL/min were excluded. Patients were classified by dose reduction criteria for the different DOACs (i.e., full dose for all [FULL], reduced dose for all [REDUCED], patients not included in previous groups [INTERMEDIATE]). Results We included 12,866 patients from the ETNA-AF EU study. According to the SmPC dose reduction criteria, the percentage of patients that would be eligible for a dose reduction in the ETNA population was highly heterogenous across different DOACS: 5.7% for apixaban, 16.8% for rivaroxaban, 23.8% for edoxaban and 52.9% for dabigatran. Moreover, differences in the dose reduction criteria included in each SmPC was reflected by the distribution of patients in the three pre-specified groups. Among the 11,003 assignable patients, 42.4% would receive a full dose, 5.1% would receive a reduced dose and the largest percentage, 52.5%, was in the INTERMEDIATE group, which would receive either a full or reduced dose of any DOAC depending on the selected agent. Of the patients included in the INTERMEDIATE group, 65.2% received a full dose of edoxaban due to its specific labelling. Interestingly, the INTERMEDIATE group included the vast majority of patients known to be at risk of adverse events: very elderly (i.e., ≥85 yrs; 76.5%), frail as per investigator (73.3%), history of previous stroke (60.4%) or history of bleeding (61.3%). Clinical outcomes at four years were significantly higher in both the INTERMEDIATE and the REDUCED groups compared to the FULL group, with the only exception of haemorrhagic stroke (Table). Conclusion(s): According to the different dose reduction criteria of currently available DOACs, notable percentage of patients could receive either a full or a reduced dose depending on the DOAC chosen by the physician. Considering that the chosen dose of the DOAC has an impact on clinical outcomes, patients in the INTERMEDIATE group need careful assessment, which warrants further analysis.

Assessing Outcomes in Patients With Multiple Myeloma Postautologous Stem Cell Transplantation: Contrasting the Effects of Melphalan Dosages at 200 mg/m2 versus 140 mg/m2

BackgroundNo standard criteria for dose reduction exists for high-dose melphalan for autologous stem cell transplantation (ASCT) for multiple myeloma (MM) due to limited and conflicting evidence. ObjectiveTo evaluate efficacy and safety of standard dose (200 mg/m2 = Mel200) versus reduced dose 140 mg/m2 = Mel140) of melphalan in patients with MM undergoing ASCT. DesignA single-center retrospective review of adults with MM for their first ASCT between January 1, 2010, and November 1, 2022, who received Mel200 or Mel140 as conditioning. Primary endpoint was progression-free survival (PFS). Secondary safety and efficacy endpoints included overall survival (OS), incidence of febrile neutropenia and acute kidney injury, and time to engraftment. Subgroup analyses were performed based on patient age and renal function. ResultsA total of 322 patients were included in the study, 240 in the Mel200 group and 82 in the Mel140 group. Baseline demographics were similar except patients receiving Mel140 were on average older and had worse kidney function. PFS at 2 years was not different between groups (P = .2335). No difference existed in 2 year PFS or OS for patients < 65 years of age versus ≥ 65 years of age or for patients with CrCl 30-59 mL/min versus CrCl ≥ 60 mL/min within either Mel200 group or Mel140 group (all P > .05). No differences existed between groups across all secondary outcomes. ConclusionReduced doses melphalan showed no differences in safety or efficacy outcomes versus standard dose even when analyzed based on age and renal function. Larger randomized controlled trials need to be performed to validate these findings.

Prevalence and management of proteinuria associated with vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitor treatment in advanced renal cell carcinoma, hepatocellular carcinoma, and thyroid cancer.

Vascular endothelial growth factor receptor-targeted tyrosine kinase inhibitors (VEGFR-TKIs) are often used for treatment of several types of cancer; however, they are associated with an increased risk of proteinuria, sometimes leading to treatment discontinuation. We searched PubMed and Scopus to identify clinical studies examining the incidence and risk factors for proteinuria caused by VEGFR-TKIs in patients with renal cell carcinoma, thyroid cancer, and hepatocellular carcinoma. The global incidence of proteinuria ranged from 6% to 34% for all grades of proteinuria, and from 1% to 10% for grade ≥3 proteinuria. The incidence of proteinuria did not differ significantly by cancer type, but in all three cancer types, there was a trend toward a higher incidence of proteinuria with lenvatinib than with other VEGFR-TKIs. In terms of risk factors, the incidence of proteinuria was significantly higher among Asians (including Japanese) compared with non-Asian populations. Other risk factors included diabetes mellitus, hypertension, and previous nephrectomy. When grade 3/4 proteinuria occurs, patients should be treated according to the criteria for dose reduction or withdrawal specified for each drug. For grade 2 proteinuria, treatment should be continued when the benefits outweigh the risks. Referral to a nephrologist should be considered for symptoms related to decreased renal function or when proteinuria has not improved after medication withdrawal. These management practices should be implemented universally, regardless of the cancer type.

Edoxaban for stroke prevention in atrial fibrillation and factors associated with dosing: patient characteristics from the prospective observational ETNA-AF-China registry

Real-world data on effectiveness and safety of a single non-vitamin K antagonist oral anticoagulant in the Chinese population with atrial fibrillation (AF) are limited. This study reports characteristics of patients treated with edoxaban and factors associated with dosing patterns from routine care in China. ETNA-AF-China (NCT04747496) is a multicentre, prospective, observational study enrolling edoxaban-treated patients from four economic regions with a targeted 2-year follow-up. Of the 4930 patients with AF (mean age: 70.2 ± 9.5 years; male, 57.1%), the mean creatinine clearance (CrCl), CHA2DS2-VASc, and HAS-BLED scores were 71.2 mL/min, 2.9, and 1.6. Overall, 6.4% of patients were perceived as frail by investigators. Available label dose reduction criteria (N = 4232) revealed that 3278 (77.5%) patients received recommended doses and 954 (22.5%) non-recommended doses. Northeast (53.0%) and West (43.1%) regions had the highest prescriptions of 60 mg and 30 mg recommended doses, respectively. Non-recommended 30 mg doses were more frequently prescribed in patients with antiplatelet use and history of heart failure than recommended 60 mg. Multivariate analysis identified advanced age as the strongest associated factor with non-recommended doses. Frailty had the strongest association with 30 mg except for age, and history of TIA was the most relevant factor associated with 60 mg. In conclusion, patients in the ETNA-AF-China study were predominantly aged 65 years and older, had mild-to-moderate renal impairment and good label adherence. Advanced age was associated with non-recommended doses, with frailty most common for non-recommended 30 mg and a history of TIA for the non-recommended 60 mg dose.

Real-World Management Strategies of Anticoagulated Atrial Fibrillation Patients After a Clinically Significant Bleeding Episode

BackgroundSystemic anticoagulation for stroke prevention in patients with atrial fibrillation (AF) carries inherent bleeding risks, and determining whether and when to resume anticoagulation after significant bleeding is a common dilemma. We aimed to describe the clinical characteristics of AF patients discharged after a bleeding event, document real-life thromboembolic prevention strategy (TPS), and analyse their associated clinical outcomes. MethodsWe retrospectively reviewed the charts of anticoagulated AF patients admitted for bleeding from 2017 to 2019. ResultsA total of 140 patients were included, with a mean age of 78.6 years. Four discharge groups were defined: 75 patients (53.5%) had optimal anticoagulation (OA), 37 (26.4%) had a suboptimal antithrombotic regimen (SAR; low-dose direct oral anticoagulants without dose-reduction criteria or antiplatelet therapy), 10 (7.1%) were referred for left atrial appendage occlusion (LAAO), and 18 (12.9%) left without any TPS. All-cause mortality at 2 years was high (28.6%) but not statistically different between groups (P = 0.71). Patients discharged with a TPS (OA/SAR/LAAO referral) were more likely to be readmitted for bleeding at 2 years (34% vs 0%; P = 0.002), and those discharged without a TPS had higher rates of stroke (16.6% vs 1.4%; P = 0.003). SAR yielded readmission rates for bleeding similar to resumption of OA (27% vs 34.7%; P = 0.41) but was associated with high rates of death or readmission at 2 years. ConclusionsThis real-life cohort reveals that clinicians frequently downgrade or discontinue long-term thromboembolic protection after a bleeding event despite current guideline recommendations to the contrary, and downgrading resulted in bleeding risk similar to OA.

Clinical outcomes in patients receiving oral anticoagulation stratified by the presence of dose reduction criteria and older age: a subanalysis of ENVISAGE-TAVI AF

Abstract Background/Introduction In the ENVISAGE-TAVI AF (Edoxaban vs Standard of Care and Their Effects on Clinical Outcomes in Patients Having Undergone Transcatheter Aortic Valve Implantation–Atrial Fibrillation) trial, edoxaban (EDX) was noninferior to vitamin K antagonists (VKAs) for preventing most adverse clinical events but was associated with increased major bleeding (MB). Presence of EDX dose reduction criteria applied in the trial (DRC; body weight ≤60 kg, CrCL 15–50 mL/min, concomitant use of selected P-glycoprotein-inhibitors) indicates a more vulnerable patient phenotype. Purpose Compare clinical outcomes after TAVI for AF patients with and without DRC stratified by anticoagulation strategy and age. Methods ENVISAGE-TAVI AF (NCT02943785) was a multicentre, open-label, randomised, controlled trial comparing EDX vs VKA in patients with AF as the indication for oral anticoagulation (OAC) after successful TAVI. In this analysis, outcomes—which included net adverse clinical events (NACE; composite all-cause death, myocardial infarction, ischaemic stroke, systemic thromboembolic event, valve thrombosis, or MB), intracranial haemorrhage, ischaemic stroke, all-cause death, cardiovascular (CV) death, non-CV death, MB bleeding, fatal MB bleeding, and major gastrointestinal bleeding (MGIB) —were compared in patients with vs without DRC, further stratified by OAC use, and age (&amp;lt; or ≥80 years [y]). Results Patients meeting DRC (n=637) were older, more often female, and had lower baseline CrCL than those without (n=740). In addition, these patients had significantly higher rates of NACE (P=0.0375) and all-cause death (P=0.0136). There were no differences in MB or MGIB rates between patients with vs without DRC. EDX resulted in more MB (hazard ratio [95% CI], 1.6 [1.1–2.5] and MGIB (2.6 [1.2–5.8]) than VKA only in patients without DRC. In patients aged &amp;lt;80 y meeting DRC, rates of all-cause death (P=0.0366) and CV death (P=0.0042) were significantly higher than those without DRC. Among patients aged &amp;lt;80 y, there were no differences in rates of clinical outcomes between EDX and VKA regardless of the presence or absence of DRC; Figure 1). In patients aged ≥80 y, there were no differences in rates of all-cause death, MB, or MGIB in those with or without DRC; Figure 2). Additionally in this age group, there was no difference in MB between patients on EDX and VKA both with and without DRC. However, there was more MGIB with EDX when there were no DRC. In patients aged ≥80 y with DRC, all-cause death was lower with EDX. Conclusions In this subanalysis of ENVISAGE-TAVI AF, the presence of DRC indicates a more vulnerable patient phenotype at higher risk for all-cause death after TAVI and in whom a lower EDX dose may have substantial benefits in terms of outcomes, including bleeding events, particularly in patients ≥80 y.Figure 1Figure 2

Clinical characteristics of apixaban prescription in AF patients with single dose-reduction criterion: ASPIRE (efficacy and safety of apixaban in real-world practice in Korean frail patients with AF)

Abstract Background/Introduction Previous observational studies reported that off-label underdosed apixaban might be associated with a higher risk of stroke. However, the real-world clinical practice data on the off-label underdosed apixaban in patients with atrial fibrillation (AF) who meet single dose reduction criteria remains scarce. Purpose This study aimed to evaluate the apixaban dosing pattern in patients with AF who met a single dose reduction criterion. The difference in clinical characteristics underlying the on-label and off-label underdose prescription of apixaban was also assessed. Methods The efficAcy and Safety of aPixaban In REal-world practice in Korean frail patients with AF (ASPIRE) study is a multicenter, prospective cohort study. This study included patients with AF having a single dose reduction criterion of apixaban. Study subjects were categorized into two groups according to apixaban dose (on-label 5 mg twice daily [on-label], or off-label underdose 2.5 mg twice daily [off-label]). We evaluated the difference in the clinical characteristics were evaluated. Additionally, the ‘marginal zone’ was defined as age between 75 and 80 years, weight between 60 and 65kg, and creatinine level between 1.2-1.5mg/dL. Results A total of 1997 patients were included in this analysis (mean age 74.3±7.8 years, women 55.8%); 591 (29.7%) patients were 80 years or older, 1250 (62.6%) patients had body weight 60 kg or below, and 156 (7.8%) patients had serum creatinine 1.5mg/dL or higher. Of these patients, 1022 (51.2%) patients were prescribed off-label underdose apixaban. The off-label group was older and had higher mean CHA2DS2-VASC score, Charlson Comorbidity Index, and HAS-BLED scores than the on-label group. Hypertension, heart failure, prior bleeding history, chronic kidney disease, anemia, and concomitant antiplatelet agent usage were more prevalent in the off-label group, but prior stroke history was more common in on-label group. In the age ≥ 80 years group, the marginal zone serum creatinine was more prevalent in off-label group (p=0.011). In the body weight ≤ 60 kg group, the prevalence of marginal zone bodyweight and serum creatinine were higher in off-label group (p&amp;lt;0.001 and p=0.02, respectively). In creatinine ≥ 1.5 mg/dL group, the proportion of marginal zone body weight were more common in off-label underdose group (p=0.001) (Figure). Conclusions Among AF patients with a single dose reduction criterion for apixaban, almost half of the patients were prescribed off-label underdose apixaban. Physicians were more likely to prescribe off-label underdose apixaban in patients with more frail characteristics, whereas on-label apixaban was preferred in patients with prior history of stroke. The clinical outcome of off-label underdose apixaban would be compared with the on-label standard dose in a future study.

Comparison of baseline characteristics and outcomes of on-label full dose (20mg) and off-label reduced dose (15mg) rivaroxaban in patients with atrial fibrillation in Asian elderly patients

Abstract Introduction In ROCKET-AF trial, rivaroxaban 20mg was on label dose and dose reduction criteria for rivaroxaban is creatinine clearance (CrCl) less than 50ml/min. Some Asian countries using reduced doses label compared with other global regions according to the J-ROCKET trial. Purpose The aim of this study was to assess the patients characteristic and outcomes of on-label full dose rivaroxaban and off-label reduced dose rivaroxaban in Asian elderly patients. Methods This study is a multi-center, prospective, non-interventional observational study to evaluate the efficacy and safety of rivaroxaban in atrial fibrillation patients older than 65 years old with or without renal impairment. Results A total of 1098 patients (mean age 72.8±5.8 years, 691[62.9%] males) was included and 265 patients received on label full does (20mg) rivaroxaban and 560 patients received off label reduced dose (15mg) rivaroxaban. Off label group showed older, more female patients, lower body weight, impaired CrCl and higher CHADS-VASc score. There showed no significant differences between two groups in major and minor bleeding, stroke and net-clinical outcomes. Conclusions Physicians prefer to prescribe off-label reduced dose rivaroxaban in patients with older and frail patients in Asia real world practice. There showed no differences in outcomes in these patients. Off label 15mg of rivaroxaban might be consider in specific populations.

Management of patients after total knee arthroplasty using mechanical prophylaxis and reduced doses of edoxaban: A retrospective cohort study.

Edoxaban is given as pharmacologic prophylaxis alone or in combination with mechanical prophylaxis for venous thromboembolism after total knee arthroplasty. Several choices are made regarding edoxaban dosages when used in combination with mechanical prophylaxis. This study aimed to compare efficacy and safety in patients who received edoxaban with elastic stockings after total knee arthroplasty between those who received the standard dose, including those who received a reduced dose after meeting dose reduction criteria, and those who received reduced doses without dose reduction criteria. This study included 143 patients in the standard-dose group (with 125 patients receiving dose-adjusted edoxaban 15 mg/day) and 110 patients in the low-dose group, and it compared the incidence of venous thromboembolism and bleeding events between groups. The impact of edoxaban administration on the occurrence of venous thromboembolism after total knee arthroplasty was also examined using multivariate regression analysis. Our results showed that rates of venous thromboembolism and bleeding events in patients wearing elastic stockings after total knee arthroplasty were similar in both standard- and low-dose groups. Multivariate regression analysis showed that use of reduced-dose edoxaban without dose adjustment did not correlate with the occurrence of venous thromboembolism, but edoxaban administration was significantly associated with older age and longer surgery time (odds ratio 1.84, 95% confidence interval 1.04-3.25, p=0.036; odds ratio 1.69; 95% confidence interval 1.09-2.62, p=0.019). These results suggest that reduced dose selection of edoxaban for patients who receive mechanical prophylaxis after total knee arthroplasty and post-administration pharmacological management may be useful.

Establishment of Radiation Dose Reduction Criteria for Thoracic and Abdominal CT via Systematic Spatial Resolution Evaluation

With the development of various reconstruction algorithms for CT imaging, it has become possible to perform low-dose CT examinations without compromising image quality. However, quantitative evaluation such as image noise, signal-to-noise ratio (SNR), and contrast-tonoise ratio (CNR) have been mainly used yet, while the spatial resolution and overall image quality rely on subjective assessment. Therefore, this study aimed to propose a quantitative method for evaluating spatial resolution in chest and abdominal CT scans, in order to facilitate dose reduction. For this study, a phantom was fabricated using 3D printing and scanned under chest and abdominal imaging conditions, with additional scans performed under low-dose conditions. The peak, bottom, FWHM, DFWHM, and peak-bottom were compared and analyzed. The results showed no statistically significant differences in spatial resolution parameters between all chest and abdominal protocol, with FWHM and DFWHM indicating the same distance. Even if the dose is reduced to 30 mAs in the chest CT condition and to 50 mAs in the abdominal CT condition, there will not be a big problem in terms of spatial resolution. Lastly, the indices from this study demonstrate potential as objective measures of spatial resolution when applying low-dose CT protocols.

Low-dose non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation.

In the last decade, non-vitamin K antagonist oral anticoagulants (NOACs), a new generation of OACs, were introduced to prevent thromboembolism in patients with atrial fibrillation. Although vitamin K-dependent anticoagulants have long been used as OACs, their inherent disadvantage of considerable bleeding complications has limited their use. NOACs demonstrate similar or superior clinical outcomes to those of warfarin. Although strict dose reduction criteria are recommended for NOACs, low-dose NOACs are frequently utilized, especially in Asian patients. Low-dose NOACs have shown clinical outcomes similar to those of warfarin in randomized controlled trials (RCTs) and real-world studies. However, off-label low-dose NOACs have shown inconsistent results compared with standard-dose NOACs and warfarin. Therefore, strict dose reduction criteria for NOACs should be followed until RCTs confirm the issues associated with NOAC underdosing.

External validation of AF-BLEED for predicting major bleeding and for tailoring NOAC dose in AF patients: A post hoc analysis in the ENGAGE AF-TIMI 48

ObjectiveAF-BLEED, a simple bleeding risk classifier, was found to predict major bleeding (MB) in patients with atrial fibrillation (AF) and identify AF patients at high risk of MB who might potentially benefit from a lower direct oral anticoagulant dose. This post hoc study aimed to externally validate these findings in the ENGAGE AF-TIMI 48 (Effective aNticoaGulation with factor Xa next Generation in Atrial Fibrillation–Thrombolysis in Myocardial Infarction study 48) trial. MethodsThe ENGAGE AF-TIMI 48 trial randomized AF patients to higher-dose edoxaban regimen (HDER 60/30 mg) versus lower-dose edoxaban regimen (LDER 30/15 mg), with prespecified dose reduction criteria. AF-BLEED was calculated in the modified intention-to-treat cohort (n = 21,026 patients) used for primary outcome analysis. Annualized event rates and hazard ratios (HRs) were obtained for the primary composite outcome (PCO) and its single components (MB, ischemic stroke/systemic embolism and death) to compare LDER 30 mg with HDER 60 mg in both AF-BLEED classes. ResultsAF-BLEED classified 2882 patients (13.7 %) as high-risk, characterized by a two- to three-fold higher MB risk than AF-BLEED classified low-risk patients. AF-BLEED classified high-risk patients randomized to LDER 30 mg demonstrated a 3.3 % reduction in MB at the cost of a 0.5 % increase in ischemic stroke/systemic embolism. LDER 30 mg resulted in a 3.1 % reduction of PCO compared to HDER 60 mg (HR of 0.81; 95%CI 0.65–1.01). Additional to existing dose reduction criteria, another 6 % of patients could potentially benefit of this dose adjustment strategy. ConclusionAF-BLEED could identify AF patients to be at high risk of major bleeding. Our findings support the hypothesis that LDER 30 mg might provide a reasonable option in AF patients with legitimate bleeding concerns.

Analysis of Oral Anticoagulant Dosing and Adherence to Therapy Among Patients With Nonvalvular Atrial Fibrillation

Although reduced doses of direct oral anticoagulants (DOACs) are approved for patients with nonvalvular atrial fibrillation (NVAF) at high risk of bleeding, little is known about dosing accuracy, particularly in patients with renal dysfunction. To determine whether underdosing of DOACs is associated with longitudinal adherence to anticoagulation. This retrospective cohort analysis used data from the Symphony Health claims data set. This national medical and prescription data set comprises 280 million patients and 1.8 million prescribers in the US. Patients included had at least 2 claims for NVAF between January 2015 and December 2017. The dates of analysis for this article were from February 2021 to July 2022. This study included patients with CHA2DS2-VASc scores of 2 or higher who were treated with a dose of DOACs who did and did not meet label-specified criteria for dose reduction. Logistic regression models examined factors associated with off-label dosing (ie, dosing not recommended by US Food and Drug Administration [FDA] labeling), the association of creatinine clearance with recommended DOAC dosing, and the association of DOAC underdosing and excess dosing with 1-year adherence. Among the 86 919 patients included (median [IQR] age, 74 [67-80] years; 43 724 men [50.3%]; 82 389 White patients [94.8%]), 7335 (8.4%) received an appropriately reduced dose, and 10 964 (12.6%) received an underdose not consistent with FDA recommendations, meaning that 59.9% (10 964 of 18 299) of those who received a reduced dose received an inappropriate dose. Patients who received off-label doses of DOACs were older (median [IQR] age, 79 [73-85] vs 73 [66-79] years) and had higher CHA2DS2-VASc scores (median [IQR], 5 [4-6] vs 4 [3-6]) compared with patients who received appropriate doses (as recommended by FDA labeling). Renal dysfunction, age, heart failure, and the prescribing clinician being in a surgical specialty were associated with dosing not recommended by FDA labeling. Almost one-third of patients (9792 patients [31.9%]) with creatinine clearance less than 60 mL per minute taking DOACs were either underdosed or excess-dosed not consistent with FDA recommendations. For every 10-unit decrease in creatinine clearance, the odds of the patient receiving an appropriately dosed DOAC was lower by 21%. Treatment with underdosed DOACs was associated with a lower likelihood of adherence (adjusted odds ratio, 0.88; 95% CI, 0.83-0.94) and higher risk of anticoagulation discontinuation (adjusted odds ratio, 1.20; 95% CI, 1.13-1.28) by 1 year. In this study of oral anticoagulant dosing, DOAC dosing that did not follow FDA label recommendations was observed in a substantial number of patients with NVAF, occurred more frequently in patients with worse renal function, and was associated with less-consistent long-term anticoagulation. These results suggest a need for efforts to improve the quality of DOAC use and dosing.