Clinical presentation and course of bleeding events in patients with venous thromboembolism, treated with apixaban or enoxaparin and warfarin. Results from the AMPLIFY trial

Safety and Effectiveness of Apixaban in Japanese Patients With Venous Thromboembolism in Clinical Practice - A Post-Marketing Surveillance

BACKGROUND

A post-marketing surveillance study (STANDARD-VTE) evaluated the real-world safety and effectiveness of apixaban in Japanese patients prescribed for either the treatment of venous thromboembolism (VTE) or prevention of recurrent VTE.

METHODS AND RESULTS

Patients newly initiated on apixaban were followed up for 52 weeks or 28 days post-discontinuation. Subgroup analysis was performed on patients with and without active cancer, and on patients with provoked VTE and with unprovoked VTE. A total of 1,119 patients were enrolled. Of these, 43.1% were aged ≥75 years, 46.4% had body weight ≤60 kg, and 21.3% had active cancer; mean serum creatinine was 0.76 mg/dL. The incidence of adverse drug reactions (ADRs) was 8.85%, and that of severe ADRs was 3.22%. Incidence of any bleeding, major bleeding, and recurrent VTE was 6.70%, 3.40%, and 0.80%, respectively. In patients starting apixaban 10 mg twice daily, THE incidence of any bleeding and major bleeding was 7.72% and 3.86%, respectively. In patients with active cancer, THE incidence of any bleeding and major bleeding was 16.81% and 9.24%, respectively.

CONCLUSIONS

No new safety signals of apixaban were identified in Japanese patients with VTE. In this study, the safety and effectiveness of apixaban in real-world practice was consistent with the results of the apixaban phase III trial.

Monotherapy Anticoagulation to Expedite Home Treatment of Patients Diagnosed With Venous Thromboembolism in the Emergency Department: A Pragmatic Effectiveness Trial

BACKGROUND

The objective was to test if low-risk emergency department patients with vitamin K antagonist (venous thromboembolism [VTE]; including venous thrombosis and pulmonary embolism [PE]) can be safely and effectively treated at home with direct acting oral (monotherapy) anticoagulation in a large-scale, real-world pragmatic effectiveness trial.

METHODS

This was a single-arm trial, conducted from 2016 to 2019 in accordance with the Standards for Reporting Implementation Studies guideline in 33 emergency departments in the United States. Participants had newly diagnosed VTE with low risk of death based upon either the modified Hestia criteria, or physician judgment plus the simplified PE severity index score of zero, together with nonhigh bleeding risk were eligible. Patients had to be discharged within 24 hours of triage and treated with either apixaban or rivaroxaban. Effectiveness was defined by the primary efficacy and safety outcomes, image-proven recurrent VTE and bleeding requiring hospitalization >24 hours, respectively, with an upper limit of the 95% CI for the 30-day frequency of VTE recurrence below 2.0% for both outcomes.

RESULTS

We enrolled 1421 patients with complete outcomes data, including 903 with venous thrombosis and 518 with PE. The recurrent VTE requiring hospitalization occurred in 14/1421 (1.0% [95% CI, 0.5%-1.7%]), and bleeding requiring hospitalization occurred in 12/1421 (0.8% [0.4%-1.5%). The rate of severe bleeding using International Society for Thrombosis and Haemostasis criteria was 2/1421 (0.1% [0%-0.5%]). No patient died, and serious adverse events occurred in 2.5% of venous thrombosis patients and 2.3% of patients with PE. Medication nonadherence was reported by patients in 8.0% (6.6%-9.5%) and was associated with a risk ratio of 6.0 (2.3-15.2) for VTE recurrence. Among all patients diagnosed with VTE in the emergency department during the period of study, 18% of venous thrombosis patients and 10% of patients with PE were enrolled.

CONCLUSIONS

Monotherapy treatment of low-risk patients with venous thrombosis or PE in the emergency department setting produced a low rate of bleeding and VTE recurrence, but may be underused. Patients with venous thrombosis and PE should undergo risk-stratification before home treatment. Improved patient adherence may reduce rate of recurrent VTE. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03404635.

Definition of major bleeding: Prognostic classification

BACKGROUND

In patients on anticoagulant treatment, the major bleeding (MB) definition released by the International Society of Thrombosis and Haemostasis (ISTH) is widely accepted. However, this definition identifies MBs with highly variable short-term risk of death.

OBJECTIVES

The study aims were to derive and validate a classification of ISTH-defined MBs for the risk of short-term death.

METHODS

Consecutive patients admitted for ISTH-defined MB occurring while on treatment with oral anticoagulants were included in the study and divided into a derivation and a validation cohort. Death within 30 days was the primary study outcome.

RESULTS

Among 1077 patients with MB, 64/517 and 63/560 patients in the derivation and validation cohort died, respectively. In the derivation cohort, Glasgow coma scale (GCS) <14 and shock were predictors of death; critical site bleeding and hemoglobin decrease ≥2 g/dL, or transfusion ≥ 2 units were not. GCS <14 (hazard ratio [HR], 8.67; 95% confidence interval [CI], 3.93-19.13) was predictor of death in intracranial hemorrhage (ICH) and shock at admission (HR, 4.84; 95% CI, 2.01-11.70) and pericardial bleeding (HR, 11.37; 95% CI, 1.33-97.31) in non-ICH MBs. The predictive value of GCS <14 in ICH and shock and pericardial bleeding in non-ICH MBs was confirmed in the validation cohort. None of the patients with isolated ocular or articular bleeding died. A prognostic classification of ISTH-defined MBs for the risk of short-term death is proposed as "serious," "severe," and "life-threatening" (ICH with GCS <14 or non-ICH with shock) MBs.

CONCLUSION

According to our study, ISTH-defined MBs can be stratified for the risk of death within 30 days.

Pulmonary embolism treatment. Detection of chronic thromboembolic pulmonary hypertension

The correct stratification of pulmonary embolism risk (PE) is essential for decision-making, regarding treatment and defining the patient's place of admission. In high-risk PE, urgent re-establishment of pulmonary circulation and admission to a critical unit is required. The reperfusion treatment of choice is systemic thrombolysis, although in certain situations, especially when there is a contraindication for it, we will evaluate a surgical embolectomy or one of the catheter-guided therapies. In the rest of PE, the treatment of choice will be anticoagulation. Currently, direct oral anticoagulants have become the treatment of choice for the treatment of PE, due to their better safety profile. However, low molecular weight heparins and subsequently antivitamins K, remain the most used treatment, because they are funded by the public system. In cases of PE with cardiorespiratory arrest and / or cardiogenic shock, whenever available at our center, we must consider the indication of extracorporeal membrane oxygenation. The recent creation of PE response teams (PERT team), have meant an improvement in the care of patients with intermediate-high and high risk PE. During the follow-up of patients with PE, it is essential to perform a correct screening of chronic thromboembolic pulmonary hypertension, in order to perform a correct diagnostic and therapeutic approach.

Abnormal vaginal bleeding in women of reproductive age treated with edoxaban or warfarin for venous thromboembolism: a post hoc analysis of the Hokusai-VTE study

Objective

To investigate the characteristics and outcome of abnormal vaginal bleeding in women receiving edoxaban or warfarin for treatment of venous thromboembolism (VTE).

Design and setting

Post hoc analysis of the Hokusai‐VTE study, a multicentre, randomised, double‐blind trial comparing edoxaban with warfarin for acute symptomatic VTE.

Population

Women below 50 years receiving edoxaban or warfarin for treatment of VTE.

Methods

We collected data on diagnostic measures, treatment, and clinical outcome of abnormal vaginal bleeding events.

Main outcome measures

Occurrence of major and clinically relevant nonmajor (CRNM) abnormal vaginal bleeding events.

Results

In all, 628 women aged under 50 years were treated with edoxaban and 665 with warfarin. The rate of abnormal vaginal bleeding was 15/100 person‐years (py) (95% CI 11–19) in women receiving edoxaban and 9/100 py (95% CI 6–12) in the warfarin group (hazard ratio: 1.7, 95% CI 1.1–2.5). Major abnormal vaginal bleeding occurred in eight (1.3%) women on edoxaban and in three (0.9%) women receiving warfarin [odds ratio (OR) 2.8; 95% CI 0.8–10.8], and CRNM abnormal vaginal bleeding occurred in 53 (8.4%) women treated with edoxaban and in 37 (5.6%) on warfarin therapy (OR 1.6, 95% CI 1.0–2.4). Over 85% of all vaginal bleeds were characterised by heavy menstrual bleeding. Major bleeds frequently required treatment, and in more than 75% of patients anticoagulant therapy was adjusted. The severity of clinical presentation and course of major and CRNM bleeds was mild in most patients.

Conclusions

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin. Reassuringly, most events could be managed conservatively and had a mild outcome.

Tweetable abstract

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin.

Abnormal vaginal bleeding occurred more frequently in women treated with edoxaban than with warfarin.

Clinical outcome of patients with a vitamin K antagonist-associated bleeding treated with prothrombin complex concentrate

BACKGROUND

Vitamin K antagonists (VKA) are used for the treatment of thromboembolism. Patients with severe VKA-associated bleeding require immediate restoration of haemostasis. Clinical studies on the effect of prothrombin complex concentrate (PCC) are heterogeneous with respect to outcome of bleeding.

OBJECTIVE

To evaluate the clinical outcome of patients treated with PCC for VKA-associated bleeding.

METHODS

We performed a cohort study of consecutive patients who received PCC for VKA-related bleeding in five Dutch hospitals. Data were collected by chart review on the bleeding event, international normalized ratio (INR), haemostatic efficacy, thromboembolic (TE) complications, and mortality. The primary outcome was effective haemostasis, assessed by an adaptation of the Sarode criteria with a surrogate outcome for patients with ICH without repeat CT.

RESULTS

One hundred patients were included. Mean age was 74 years, 54% were male and 79% received VKA for atrial fibrillation. Most patients presented with ICH (41%) or GI bleeding (36%). Effective haemostasis was achieved in 67/98 (68%) patients using the adapted classification. Surrogate outcomes were applied for 32 patients and data for two patients was missing. Median pre-treatment INR was 3.9 (IQR 2.9-5.8). One hour after PCC infusion, the INR was available for 50 patients and of these, 35 (70%) had an INR ≤1.4. TE complications occurred in five patients and 22 died (60% bleeding-related) within 30 days.

CONCLUSION

PCC achieved effective haemostasis in 68% of evaluable patients with VKA-associated bleeding. TE complication rates were low, but mortality rates were high, due to the large number of patients with ICH.

Clinical impact of major bleeding in patients with venous thromboembolism treated with factor Xa inhibitors or vitamin K antagonists

Factor Xa (fXa)-inhibitors are as effective and safer than vitamin-K–antagonists (VKA) in the treatment of venous thromboembolism (VTE). We previously classified the severity of clinical presentation and course of all major bleeding events from the EINSTEIN, AMPLIFY and HOKUSAI-VTE trials separately. The current aim was to combine these findings in order to increase precision, assess a class effect and analyse presentation and course for different types of bleeding, i. e. intracranial, gastro-intestinal, and other. We classified the clinical presentation and course of all major bleeding events using pre-defined criteria. Both classifications comprised four categories; one being the mildest, and four the most severe. Odds ratios (OR) were calculated for all events classified as category three or four between fXa-inhibitors and VKA recipients. Also, ORs were computed for different types of bleeding. Major bleeding occurred in 111 fXa-inhibitor recipients and in 187 LMWH/VKA recipients. The clinical presentation was classified as category three or four in 35% and 48% of the major bleeds in fXa inhibitor and VKA recipients, respectively (OR 0.59, 95% CI 0.36–0.97). For intracranial, gastro-intestinal and other bleeding a trend towards a less severe presentation was observed for patients treated with fXa inhibitors. Clinical course was classified as severe in 22% of the fXa inhibitor and 25% of the VKA associated bleeds (OR 0.83, 95% CI 0.47–1.46). In conclusion, FXa inhibitor associated major bleeding events had a significantly less severe presentation and a similar course compared to VKA. This finding was consistent for different types of bleeding.

Evaluation of bleeding in patients receiving direct oral anticoagulants

Direct oral anticoagulants (DOACs) are recognized by evidence-based treatment guidelines as the first-line option for the treatment of venous thromboembolism and prevention of stroke and systemic embolism in nonvalvular atrial fibrillation. As use of these anticoagulants has become favored over the past several years, reported bleeding-related adverse drug events with these agents has increased. In randomized clinical trials, all DOACs have a reduced risk for intracranial hemorrhage, while major and other bleeding results have varied among the agents compared to vitamin K antagonists. We have reviewed the bleeding incidence and severity from randomized and real-world data in patients receiving DOACs in an effort to provide the clinician with a critical review of bleeding and offer practical considerations for avoiding adverse events with these anticoagulants.

Abnormal vaginal bleeding in women with venous thromboembolism treated with apixaban or warfarin

Abnormal vaginal bleeding can complicate direct oral anticoagulant (DOAC) treatment. We aimed to investigate the characteristics of abnormal vaginal bleeding in patients with venous thromboembolism (VTE) receiving apixaban or enoxaparin/warfarin. Data were derived from the AMPLIFY trial. We compared the incidence of abnormal vaginal bleeding between patients in both treatment arms and collected information on clinical presentation, diagnostic procedures, management and outcomes. In the AMPLIFY trial, 1122 women were treated with apixaban and 1106 received enoxaparin/warfarin. A clinically relevant non-major (CRNM) vaginal bleeding occurred in 28 (2.5 %) apixaban and 24 (2.1 %) enoxaparin/warfarin recipients (odds ratio [OR] 1.2, 95 % confidence interval [CI] 0.7-2.0). Of all CRNM bleeds, 28 of 62 (45 %) and 24 of 120 (20 %) were of vaginal origin in the apixaban and enoxaparin/warfarin group, respectively (OR 3.4; 95 % CI 1.8-6.7). Premenopausal vaginal bleeds on apixaban were characterised by more prolonged bleeding (OR 2.3; 95 %CI 0.5-11). In both pre- and postmenopausal vaginal bleeds, diagnostic tests were performed in six (21 %) and in seven (29 %) apixaban and enoxaparin/warfarin treated patients, respectively. Medical treatment was deemed not necessary in 16 (57 %) apixaban and 16 (67 %) enoxaparin/warfarin recipients. The severity of clinical presentation and course of the bleeds was mild in 75 % of the cases in both groups. In conclusion, although the absolute number of vaginal bleeding events is comparable between apixaban and enoxaparin/warfarin recipients, the relative occurrence of vaginal bleeds is higher in apixaban-treated women. The characteristics and severity of bleeding episodes were comparable in both treatment arms.