Drug-drug interaction between dexamethasone and direct-acting oral anticoagulants: a nested case-control study in the National COVID Cohort Collaborative (N3C).

OBJECTIVE: The goal of this work is to evaluate if there is an increase in the risk of thromboembolic events (TEEs) due to concomitant exposure to dexamethasone and apixaban or rivaroxaban. Direct oral anticoagulants (DOACs), as well as corticosteroid dexamethasone, are commonly used to treat individuals hospitalised with COVID-19. Dexamethasone induces cytochrome P450-3A4 enzyme that also metabolises DOACs apixaban and rivaroxaban. This raises a concern about possible interaction between dexamethasone and DOACs that may reduce the efficacy of the DOACs and result in an increased risk of TEE. DESIGN: We used nested case-control study design. SETTING: This study was conducted in the National COVID Cohort Collaborative (N3C), the largest electronic health records repository for COVID-19 in the USA. PARTICIPANTS: Study participants were adults over 18 years who were exposed to a DOAC for 10 or more consecutive days. Exposure to dexamethasone was at least 5 or more consecutive days. PRIMARY AND SECONDARY OUTCOME MEASURES: Our primary exposure variable was concomitant exposure to dexamethasone for 5 or more days after exposure to either rivaroxaban or apixaban for 5 or more consecutive days. We used McNemar's Χ2 test and adjusted logistic regression to evaluate association between concomitant use of dexamethasone with either apixaban or rivaroxaban. RESULTS: McNemar's Χ2 test did not find a discernible association of TEE in patients concomitantly exposed to dexamethasone and a DOAC (χ2=0.5, df=1, p=0.48). In addition, a conditional logistic regression model did not find an increase in the risk of TEE (adjusted OR 1.15, 95% CI 0.32 to 4.18). CONCLUSION: This nested case-control study did not find evidence of an association between concomitant exposure to dexamethasone and a DOAC with an increase in risk of TEE. Due to small sample size, an association cannot be completely ruled out.

Anticoagulants as Potential SARS-CoV-2 Mpro Inhibitors for COVID-19 Patients: In Vitro, Molecular Docking, Molecular Dynamics, DFT, and SAR Studies.

In this article, 34 anticoagulant drugs were screened in silico against the main protease (Mpro) of SARS-CoV-2 using molecular docking tools. Idraparinux, fondaparinux, eptifibatide, heparin, and ticagrelor demonstrated the highest binding affinities towards SARS-CoV-2 Mpro. A molecular dynamics study at 200 ns was also carried out for the most promising anticoagulants to provide insights into the dynamic and thermodynamic properties of promising compounds. Moreover, a quantum mechanical study was also conducted which helped us to attest to some of the molecular docking and dynamics findings. A biological evaluation (in vitro) of the most promising compounds was also performed by carrying out the MTT cytotoxicity assay and the crystal violet assay in order to assess inhibitory concentration 50 (IC50). It is worth noting that ticagrelor displayed the highest intrinsic potential for the inhibition of SARS-CoV-2 with an IC50 value of 5.60 µM and a safety index of 25.33. In addition, fondaparinux sodium and dabigatran showed promising inhibitory activities with IC50 values of 8.60 and 9.40 µM, respectively, and demonstrated safety indexes of 17.60 and 15.10, respectively. Moreover, the inhibitory potential of the SARS-CoV-2 Mpro enzyme was investigated by utilizing the SARS-CoV-2 Mpro assay and using tipranavir as a reference standard. Interestingly, promising SARS-CoV-2 Mpro inhibitory potential was attained for fondaparinux sodium with an IC50 value of 2.36 µM, surpassing the reference tipranavir (IC50 = 7.38 µM) by more than three-fold. Furthermore, highly eligible SARS-CoV-2 Mpro inhibitory potential was attained for dabigatran with an IC50 value of 10.59 µM. Finally, an SAR was discussed, counting on the findings of both in vitro and in silico approaches.

Evaluation of Novel Guanidino-Containing Isonipecotamide Inhibitors of Blood Coagulation Factors against SARS-CoV-2 Virus Infection.

Coagulation factor Xa (fXa) and thrombin (thr) are widely expressed in pulmonary tissues, where they may catalyze, together with the transmembrane serine protease 2 (TMPRSS2), the coronaviruses spike protein (SP) cleavage and activation, thus enhancing the SP binding to ACE2 and cell infection. In this study, we evaluate in vitro the ability of approved (i.e., dabigatran and rivaroxaban) and newly synthesized isonipecotamide-based reversible inhibitors of fXa/thr (cmpds 1-3) to hinder the SARS-CoV-2 infectivity of VERO cells. Nafamostat, which is a guanidine/amidine antithrombin and antiplasmin agent, disclosed as a covalent inhibitor of TMPRSS2, was also evaluated. While dabigatran and rivaroxaban at 100 µM concentration did not show any effect on SARS-CoV-2 infection, the virus preincubation with new guanidino-containing fXa-selective inhibitors 1 and 3 did decrease viral infectivity of VERO cells at subtoxic doses. When the cells were pre-incubated with 3, a reversible nanomolar inhibitor of fXa (Ki = 15 nM) showing the best in silico docking score toward TMPRSS2 (pdb 7MEQ), the SARS-CoV-2 infectivity was completely inhibited at 100 µM (p < 0.0001), where the cytopathic effect was just about 10%. The inhibitory effects of 3 on SARS-CoV-2 infection was evident (ca. 30%) at lower concentrations (3-50 µM). The covalent TMPRSS2 and the selective inhibitor nafamostat mesylate, although showing some effect (15-20% inhibition), did not achieve statistically significant activity against SARS-CoV-2 infection in the whole range of test concentrations (3-100 µM). These findings suggest that direct inhibitors of the main serine proteases of the blood coagulation cascade may have potential in SARS-CoV-2 drug discovery. Furthermore, they prove that basic amidino-containing fXa inhibitors with a higher docking score towards TMPRSS2 may be considered hits for optimizing novel small molecules protecting guest cells from SARS-CoV-2 infection.

Impact of the COVID-19 pandemic on England's national prescriptions of oral vitamin K antagonist (VKA) and direct-acting oral anticoagulants (DOACs): an interrupted time series analysis (January 2019-February 2021).

BACKGROUND: Direct-acting oral anticoagulants (DOACs) were developed as an alternative to warfarin to treat and prevent thromboembolism, including stroke prevention in non-valvular atrial fibrillation patients. The COVID-19 pandemic could increase the risk of stroke and/or the risk of bleeding in patients due to nonadherence or sub/supra-optimal dosing. OBJECTIVE: To investigate DOAC prescription trends in England's community settings during the complete first wave of COVID-19 pandemic. METHODS: Descriptive and interrupted time series (ITS) analyses were conducted to examine the prescription patterns of DOACs (dabigatran, rivaroxaban, apixaban and edoxaban) and warfarin for primary care patients in the English Prescribing Dataset from January 2019 to February 2021, with March 2020 as the cut-off point. RESULTS: A 19% increase in mean DOAC's accompanied with 20% warfarin prescriptions decline was observed. ITS modelling showed an increase in DOAC prescription volume in March 2020 (+7 million items, p = 0.008). The pre-existing upward trend in DOAC prescriptions slowed during the period (-427,000 items, p = 0.007). Apixaban was the most frequently used DOAC and had the largest step-change in March 2020 (+5 million items, p = 0.010). The mean monthly combined cost of DOACs and warfarin was higher during the period. DOAC prescription trends were consistent across England's regions. Conclusion: The overall oral anticoagulants use in this period was lower than expected, indicating a medical needs gap, possibly due to adherence issues. The potential clinical and logistical consequences warrant further study to identify contributing factors and mitigate avoidable risks.

An Update of the Efficacy and Comparative Characteristics of Direct (New) Oral Anticoagulants (DOACs).

Direct (New-generation) Oral Anticoagulants (DOACs) have emerged as effective agents which are used in place of vitamin-K antagonists in treatment and prophylaxis of Venous Thromboembolism (VTE), atrial fibrillation and other thrombotic diseases. Among them, the FIIa- direct thrombin inhibitor dabigatran and FXa inhibitors (rivaroxaban, apixaban, edoxaban) are the most broadly used. Anticoagulant dosing may differ under special considerations. The patients' physiological reserves, organ functional status and failures should be taken into account in clinical decision-making processes. The advantages and drawbacks of each specific agent should be weighed with special regard to metabolism, pharmacokinetics and pharmacodynamics, along with the efficiency of the agents in different indications. This article aims to review the most recent literature to highlight the usage and efficacy of the agents in different clinical conditions.

Prior use of anticoagulation is associated with a better survival in COVID-19.

Coronavirus disease 2019 (COVID-19) is associated with a high incidence of venous and arterial thromboembolic events. The role of anticoagulation (AC) prior to hospital admission and how different types of oral AC influences the outcome of COVID-19 is currently unknown. This observational study compares the outcome in COVID-19 patients with prior use of direct oral anticoagulants (DOAC) or vitamin K antagonists (VKA), and without prior use of AC. We collected the baseline characteristics and outcomes of COVID-19 patients presented to the emergency department of Bernhoven Hospital, the Netherlands. The primary outcome was all-cause mortality within 30 days and analyzed in a multivariable Cox proportional hazards model including age, sex, symptom duration, home medication, and comorbidities. We included 497 patients, including 57 patients with DOAC (11%) and 53 patients with VKA (11%). Patients with AC had a lower body temperature and lower C-reactive protein levels. Comparing the primary outcome in patients with AC (DOAC or VKA) and no AC, the adjusted hazard ratio (aHR) was 0.64 (95% CI 0.42-0.96, P = 0.03). Comparing DOAC and no AC, the aHR was 0.53 (95% CI 0.32-0.89, P = 0.02) and comparing VKA and no AC, the aHR was 0.77 (95% CI 0.47-1.27, P = 0.30). In a subgroup analysis of DOAC, all nine patients with prior use of dabigatran survived within 30 days. In this observational study, the prior use of AC is associated with a better survival of COVID-19. DOAC, especially dabigatran, might have additional beneficial effects.

"I just didn't want to trust it at all": Atrial fibrillation patient's treatment experience of rivaroxaban and warfarin.

BACKGROUND: In the treatment of atrial fibrillation (AF), anticoagulant medications such as warfarin and rivaroxaban are commonly prescribed to reduce the risk of ischaemic strokes, and other thromboembolic events. Research has highlighted advantages and disadvantages of each of these medications, but there remains an absence of qualitative evidence regarding the lived experiences of AF patients. The present study helps address this gap and obtain a greater understanding of the patient experience and beliefs surrounding their anticoagulant medication. METHOD: Semi-structured qualitative interviews with a purposive sample of 20 participants (10 warfarin, 10 rivaroxaban). Interviews were transcribed verbatim and thematically analysed. RESULTS: Data analysis led to the generation of three key themes: positive perceptions of medication, distrust of alternatives, and inconsistencies in support experiences. CONCLUSIONS: Positive perceptions of one anticoagulant medication (ACM) and distrust of alternatives may influence patients' confidence in switching medications. This is potentially problematic where there is a lack of patient engagement in medication changes, as seen during the COVID pandemic. Gaps in patient understanding of anticoagulation, including lack of clarity around medications selection and misconceptions about treatment, were evident. By addressing these misconceptions, clinicians may be better positioned to support people with AF in self-management of their ACM.

Potential Dexamethasone-Direct Oral Anticoagulant Drug Interaction: Is This a Concern in COVID?

OBJECTIVE: To evaluate the literature on a potential dexamethasone-direct oral anticoagulant (DOAC) drug interaction and provide management considerations with COVID hypercoagulability. DATA SOURCES: A search of EMBASE, PubMed, and Google Scholar (January 1990 to May 2021), limited to the English language, using applicable search terms resulted in 137 articles, with 21 relevant articles included. Regulatory agency and clinical guidance documents were also reviewed. STUDY SELECTION AND DATA EXTRACTION: Included articles describe in vitro or in vivo animal or human data for dexamethasone induction of cytochrome P450 (CYP) 3A4 or P-glycoprotein (P-gp). DATA SYNTHESIS: Dexamethasone has the potential to interact with the DOACs via CYP3A4 and/or P-gp induction. Only apixaban and rivaroxaban have CYP3A4 metabolism. Dexamethasone can increase CYP3A4 activity by up to 70% and reduce the area under the concentration-time curve (AUC) of CYP3A4 substrates by >40%, which is consistent with criteria for a weak CYP inducer. In rodents, dexamethasone P-gp induction is associated with AUC reductions of 20% to 50%. Human data are lacking. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Severe COVID-19 infection is associated with hypercoagulability. Although heparins are the preferred anticoagulants for hospitalized COVID-19 patients, DOACs are being utilized. Dexamethasone is recommended for hospitalized COVID-19 patients requiring supplemental oxygen. The concurrent use of dexamethasone and apixaban or rivaroxaban in such patients carries the potential for reduced anticoagulant effect during a state of heightened thrombotic risk. CONCLUSIONS: Concurrent use of dexamethasone and apixaban or rivaroxaban in hospitalized COVID-19 patients with laboratory evidence of COVID coagulopathy should be avoided until higher-quality data are available.

Thromboelastography utilization for dabigatran reversal in a patient with acute kidney injury.

PURPOSE: This case report describes utilization of thromboelastography (TEG) in the setting of an acute major bleed in a patient on dabigatran who had concomitant acute kidney injury. SUMMARY: An 80-year-old female presented to the emergency department after a fall with complaints of pain in her knee, shoulder, and hip. Her medical history was significant for coronary artery disease, for which she took clopidogrel 75 mg daily, and atrial fibrillation, for which she took dabigatran 150 mg twice daily. The physical exam was remarkable for pain within the shoulder, hip, and knee, which had swelling and ecchymosis that extended into the right thigh. Given the possibility of compartment syndrome with multiple possible etiologies of coagulopathy, TEG and computed tomography angiography (CTa) of the right lower extremity were performed. The initial TEG showed prolonged R time and activated clotting time, indicating clotting factor dysfunction with no additional coagulopathy noted, including antiplatelet effects. On the basis of the TEG and CTa findings, it was decided to reverse dabigatran with 5 grams of idarucizumab. Approximately 1 hour after administration of idarucizumab, the patient was taken to interventional radiology where a limited angiogram of the right lower extremity showed no active extravasation. Because of the patient's renal dysfunction and the possibility of rebound hypercoaguability, repeat TEG tests were ordered at 4 and 8 hours after the initial reversal to ensure clearance of idarucizumab-dabigatran complexes. The repeat TEG values showed complete reversal of the initial coagulopathy noted. During the admission, the patient required no blood transfusions or surgical interventions and all her initial laboratory results improved. CONCLUSION: Serial TEG testing was successful at managing multiple coagulopathies in a patient at risk for trauma-induced compartment syndrome.

An unexpected case of recurrence of pulmonary embolism in a patient recovered from COVID19 in full regimen dose of direct oral anticoagulant drug.

BACKGROUND: Coronavirus Disease 2019 (COVID-19) is a pandemic affecting all countries in the world. Italy has been particularly afflicted by the health emergency, and since the peak phase has passed, major concern regarding medium to long term complications due to COVID-19 is arising. Little is known in literature regarding thromboembolic complications once healed after COVID-19. CASE PRESENTATION: A 51-year-old patient recovered from COVID-19 pneumonia complicated by pulmonary embolism (PE) came to the hospital for palpitations and chest pain. Although he was on treatment dose of direct oral anticoagulation (DOAC), massive recurrent PE was diagnosed. CONCLUSION: In the early post COVID-19 era, the question remains regarding the efficacy of DOACs in COVID-19 patients.

[Effect of anticoagulant therapy on the course of COVID-19 in comorbid patients].

INTRODUCTION: Analysis of the pathogenesis of coronavirus infection caused SARS-CoV-2 indicates a significant impact of hemorheological disorders on its course and outcomes. It is known that chronic cardiovascular diseases are associated with the risk of severe course and lethal outcomes both in COVID-19 and other infectious diseases. Therefore, in each case it is necessary to study the interaction and mutual influence of different components of the treatment program prescribed to such patients.The purpose of this work was to evaluate the effect of coagulation activity on the course of a novel coronavirus infection (COVID-19) and to justify the management of comorbid patients having been received novel oral anticoagulants (NOACs) in previously selected doses according to indications in concomitant somatic diseases. MATERIAL AND METHODS: Total 76 cases of confirmed coronavirus infection in patients who had been received initial therapy on an outpatient basis were analyzed. 26 patients who received NOACs (rivaroxaban, apixaban, dabigatran) made up the main group and 50 - the comparison (control) group in which patients had not been administered any drugs that affect blood clotting until the episode of COVID-19. All patients have been prescribed therapy following the Provisional guidelines «Prevention, diagnosis and treatment of coronavirus infection (COVID-19)¼ (https://static-0.minzdrav.gov.ru/system/attachments/attaches/). RESULTS AND DISCUSSION: The number of hospitalizations was significantly fewer in the group of patients who had been received NOACs (19 vs. 66% in the control group). No deaths or cases of severe respiratory and/or renal failure were observed in the main group, while adverse outcomes were noted in 14% of patients who had not been administered these drugs. CONCLUSION: Taking NOACs reduces the probability of severe course and adverse outcomes in the development of coronavirus infection caused by SARS-CoV-2, which indicates a significant contribution of coagulation mechanisms to the pathogenesis in COVID-19. There were no indications for drug replacement and correction of anticoagulant therapy regimens in patients who received adequate therapy with oral anticoagulants for treating a non-severe form of coronavirus infection in ambulatory patient settings.

Direct oral anticoagulant plasma levels' striking increase in severe COVID-19 respiratory syndrome patients treated with antiviral agents: The Cremona experience.

BACKGROUND: Antiviral drugs are administered in patients with severe COVID-19 respiratory syndrome, including those treated with direct oral anticoagulants (DOACs). Concomitant administration of antiviral agents has the potential to increase their plasma concentration. A series of patients managed in the Cremona Thrombosis Center were admitted at Cremona Hospital for SARS-CoV-2 and started antiviral drugs without stopping DOAC therapy. DOAC plasma levels were measured in hospital and results compared with those recorded before hospitalization. METHODS: All consecutive patients on DOACs were candidates for administration of antiviral agents (lopinavir, ritonavir, or darunavir). Plasma samples for DOAC measurement were collected 2to 4 days after starting antiviral treatment, at 12 hours from the last dose intake in patients on dabigatran and apixaban, and at 24 hours in those on rivaroxaban and edoxaban. For each patient, C-trough DOAC level, expressed as ng/mL, was compared with the one measured before hospitalization. RESULTS: Of the 1039 patients hospitalized between February 22 and March 15, 2020 with COVID-19 pneumonia and candidates for antiviral therapy, 32 were on treatment with a DOAC. DOAC was stopped in 20 and continued in the remaining 12. On average, C-trough levels were 6.14 times higher during hospitalization than in the pre-hospitalization period. CONCLUSION: DOAC patients treated with antiviral drugs show an alarming increase in DOAC plasma levels. In order to prevent bleeding complications, we believe that physicians should consider withholding DOACs from patients with SARS-CoV-2 and replacing them with alternative parenteral antithrombotic strategies for as long as antiviral agents are deemed necessary and until discharge.