Rivaroxaban: a review of its use in the treatment of deep vein thrombosis or pulmonary embolism and the prevention of recurrent venous thromboembolism

Primary ovarian insufficiency associated with lenvatinib therapy in a patient with hepatocellular carcinoma: A case report

The therapeutic effects of molecular targeted drugs are, in some cases, more pronounced than those of conventional chemotherapy, and their introduction as a standard treatment is increasing. The present report describes a case of ovarian insufficiency in a young woman caused by tyrosine kinase inhibitor lenvatinib. The 25-year-old woman received lenvatinib (8 mg/day) for 98 days as preoperative chemotherapy for hepatocellular carcinoma. Blood testing the day before starting lenvatinib administration indicated 4.40 mIU/ml luteinizing hormone (LH), 5.2 mIU/ml follicle-stimulating hormone (FSH) and age-equivalent hormone values. Amenorrhea occurred after the start of administration, and 48 days later, the LH level was 41.8 mIU/ml and the FSH level was 44 mIU/ml, indicating a decrease in ovarian function. The patient underwent hepatectomy, and 49 days after the end of lenvatinib administration, the LH level had improved to 4.5 mIU/ml and the FSH level had improved to 2.5 mIU/ml. After the hepatectomy, the patient began to have regular menstrual cycles once again. Ovarian toxicity has not been recognized as a side effect of lenvatinib. However, the present report describes primary ovarian insufficiency considered to be caused by this drug. Potential damage to ovarian function may need to be considered when molecular targeted drugs with the same mechanism of action as lenvatinib are used in young women.

Heparin-induced thrombocytopenia associated with low-molecular-weight heparin: clinical feature analysis of cases and pharmacovigilance assessment of the FAERS database

Background: Unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) are commonly used anticoagulants for the management of arterial and venous thromboses. However, it is crucial to be aware that LMWH can, in rare cases, lead to a dangerous complication known as heparin-induced thrombocytopenia (HIT). The objective of this study was to evaluate the pharmacovigilance and clinical features of HIT associated with LMWH, as well as identify treatment strategies and risk factors to facilitate prompt management. Methods: We extracted adverse event report data from the FDA Adverse Event Reporting System (FAERS) database for pharmacovigilance assessment. Case reports on LMWH-induced thrombocytopenia dated up to 20 March 2023 were collected for retrospective analysis. Results: Significantly elevated reporting rates of HIT were shown in adverse event (AE) data of LMWHs in the FAERS database, while tinzaparin had a higher proportional reporting ratio (PRR) and reporting odds ratio (ROR) than other LMWHs, indicating a greater likelihood of HIT. Case report analysis indicated that a total of 43 patients showed evidence of LMWH-induced thrombocytopenia with a median onset time of 8 days. Almost half of the events were caused by enoxaparin. LMWHs were mainly prescribed for the treatment of embolism and thromboprophylaxis of joint operation. Patients with a history of diabetes or surgery appeared to be more susceptible to HIT. Clinical symptoms were mostly presented as thrombus, skin lesion, and dyspnea. Almost 90% of the patients experienced a platelet reduction of more than 50% and had a Warkentin 4T score of more than 6, indicating a high likelihood of HIT. In all patients, LMWHs that were determined to be the cause were promptly withdrawn. Following the discontinuation of LMWHs, almost all patients were given alternative anticoagulants and eventually achieved recovery. Conclusion: LMWH-induced thrombocytopenia is rare but serious, with increased risk in patients with diabetes or a surgical history. Prompt recognition and management are crucial for the safe use of LMWHs.

A retrospective study of real-world effectiveness and safety of rivaroxaban in patients with non-valvular atrial fibrillation and venous thromboembolism in Saudi Arabia

Background

Real-world evidence on factor Xa inhibitor (rivaroxaban) prescribing patterns, safety, and efficacy in patients with non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE) is rare. Herein, we sought to examine the above outcomes in the largest academic center in the Kingdom of Saudi Arabia (KSA).

Methods

This is a retrospective observational study designed to examine the prescribing pattern, safety and real-world effectiveness of the factor Xa inhibitor rivaroxaban in patients with NVAF and VTE. Data on rivaroxaban prescriptions were collected and analyzed. Bleeding outcomes were defined as per the International Society on Thrombosis and Hemostasis (ISTH) definition.

Results

A total of 2,316 patients taking rivaroxaban recruited through several departments of King Saud University Medical City (KSUMC). The mean age was 61 years (±17.8) with 55% above the age of 60 and 58% were females. Deep vein thrombosis and pulmonary embolism (VTE) was the most prevalent reason for prescribing rivaroxaban, followed by NVAF. A total daily dosage of 15 mg was given to 23% of the patients. The incidence rate of recurrent thrombosis and recurrent stroke was 0.2%. Furthermore, rivaroxaban had a 0.04 percent incidence rate of myocardial infarction. Half of the patients with recurrent thrombosis and stroke were taking 15 mg per day. The incidence rate of major bleeding was 1.1%. More over half of the patients who experienced significant bleeding were taking rivaroxaban at a dosage of 20 mg per day. According to the HAS-BLED Score (>2 score), 48 percent of patients who experienced significant bleeding had a high risk of bleeding. Non-major bleeding occurred in 0.6% of cases. Similarly, 40% of patients with non-major bleeding were taking rivaroxaban at a dosage of 20 mg per day. According to the HAS-BLED Score, just 6.6% of these individuals had a high risk of bleeding. 93.4% of the patients, on the other hand, were at intermediate risk.

Conclusion

The prescription of rivaroxaban in this real-life cohort study differs from the prescribing label and the outcomes of a phase 3 randomised clinical trial. However, for individuals with VTE and NVAF, the 20 mg dose looked to be more efficacious than the pivotal trial outcomes. Furthermore, among patients with VTE and NVAF, rivaroxaban was linked to a decreased incidence of safety events such as recurrent thrombosis, recurrent stroke, MI, major bleeding, and non-major haemorrhage in a real-world environment.

Is there consensus on the perioperative management of Xa inhibitors in patients undergoing elective spine surgery?-A survey of current spine surgeon practices

BACKGROUND

Factor Xa inhibitors (Xai) are an increasingly common consideration in perioperative anticoagulation management. However, there no existing guidelines established for use in Spine Surgery. This survey study aims to capture current practice trends regarding the perioperative management of Xai among spine surgeons.

METHODS

An 11-question survey was sent to all surgeon members of 3 spinal surgery societies. Responses were remitted anonymously. Questions characterized the background and experience of the respondent and inquired into their current perioperative Xai and other anticoagulant management. Questions were all single-best option, multiple-choice.

RESULTS

A total of 116 surveys were received. Twenty-six (22.4%) were from neurosurgeons and 90 (77.6%) were from orthopedic surgeons. Practiced preoperative Xai hold length tended to be longer than recommended by the respondent's medical colleagues. Only 65.2% (P≤0.0001) of respondents practiced in agreement with the recommendations of their medical colleagues. Postoperative Xai holds trended toward longer holds than that of other anticoagulants with 37.9% (P=0.0125) of respondents showed differences within their own practice between length of Xai hold and length of other anticoagulant holds. One out of four respondents reported noticing a change in the rate of perioperative bleeding complications among Xai patients. Despite reported increased bleeding issues, only 39% of those who noted this increase in bleeding complications reported they would hold a Xai longer than other anticoagulants.

CONCLUSIONS

There exists a wide range of recommended and practiced chronic anticoagulant hold lengths. This inconsistency likely highlights conflicting risk aversion among surgeons, between complications which are viewed as medical (i.e., thromboembolism and stroke) vs. surgical (i.e., compressive hematoma). Yet, survey responses suggest the length of Xai hold times did not necessarily reflect the surgeon's experience with postoperative bleeding complications in Xai patients. These inconsistent practices highlight the need for further research that can establish guidelines for perioperative management of Xai patients undergoing spine surgery.

KEYWORDS

Anticoagulants; factor Xa inhibitors (factor Xai); spine; orthopedic surgery; neurosurgery.

Prophylaxis with rivaroxaban after laparoscopic sleeve gastrectomy could reduce the frequency of portomesenteric venous thrombosis

INTRODUCTION

Portal and mesenteric venous thrombosis is a rare but potentially serious complication after laparoscopic sleeve gastrectomy. There are no consistent studies that prove the safety and effectiveness of oral anticoagulant thromboprophylaxis with rivaroxaban after laparoscopic sleeve gastrectomy. The objective was to evaluate the effect of rivaroxaban on the frequency of portal and mesenteric venous thrombosis and its safety profile after laparoscopic sleeve gastrectomy.

MATERIALS AND METHODS

This retrospective analysis of prospectively collected data includes all laparoscopic sleeve gastrectomies performed by a single surgeon at Pontificia Universidad Católica de Chile Hospital between January 2009 and June 2019. All patients received low molecular weight heparin thromboprophylaxis during the whole hospital stay. Between July 2012 and June 2019, patients received additional post-discharge thromboprophylaxis with rivaroxaban. Patient demographics, impaired renal, post-surgical portal and mesenteric venous thrombosis, and bleeding episodes were registered.

RESULTS

A total of 516 patients were identified; 95 patients were excluded. Results for 421 patients were analysed: 198 received only intrahospital thromboprophylaxis (group 1) and 223 received additional post-discharge thromboprophylaxis with rivaroxaban (group 2). There was no statistically significant difference between the two groups concerning age, sex and body mass index. In group 1, four cases of portal and mesenteric venous thrombosis were registered and no cases were reported in group 2 (p < 0.05). All cases occurred before 30 days after surgery. No bleeding episodes and no adverse reactions were detected in group 2.

CONCLUSIONS

Thromboprophylaxis during the whole hospital stay (two to three days), followed by rivaroxaban 10mg once daily for 10 days after discharge (completing in total 13-14 days of prophylaxis), could reduce cases of post-surgical portal and mesenteric venous thrombosis without an increase in bleeding complications.

Rivaroxaban: A Review for Secondary CV Prevention in CAD and PAD

Secondary cardiovascular (CV) prevention in patients with vascular disease [e.g. coronary (CAD) and peripheral (PAD) artery disease] is crucial and typically involves antiplatelet therapy with aspirin; however, managing residual ischaemic and bleeding risks in CV disease (CVD) remains a challenge. Combining the oral anticoagulant rivaroxaban (Xarelto^®) with aspirin targets both the platelet and thrombotic processes of atherosclerosis, a common pathophysiological process associated with CVD. In the global COMPASS trial (n > 27,000), rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily (vs aspirin alone) significantly reduced the risk of the primary composite major adverse CV event (MACE) outcome (i.e. myocardial infarction, stroke or CV death) in adults with stable CAD and/or PAD and, in those with PAD, significantly reduced the risk of the composite major adverse limb event (MALE) outcome. Rivaroxaban + aspirin treatment was generally well tolerated; however, the risk of the composite major bleeding outcome, but not intracranial or fatal bleeding, was significantly higher with rivaroxaban + aspirin than aspirin. The increased risk for the composite major bleeding outcome did not negate the composite net clinical benefits of rivaroxaban + aspirin for secondary CV prevention, with rivaroxaban + aspirin especially beneficial in those with a greater CV risk at baseline. Ongoing clinical experience is required to fully define the role of rivaroxaban + aspirin in secondary CV prevention. In the meantime, dual therapy with rivaroxaban + aspirin is an important emerging option for secondary CV prevention of atherothrombotic events in adults with CAD or symptomatic PAD who are at high risk of ischaemic events.

Design, synthesis and biological evaluation of anthranilamide derivatives as potential factor Xa (fXa) inhibitors

Factor Xa (fXa) is a crucial player in various thromboembolic disorders. Inhibition of fXa can provide safe and effective antithrombotic effects. In this study, a series of anthranilamide compounds were designed by utilizing structure-based design strategies. Optimization at P1 and P4 groups led to the discovery of compound 16g: a highly potent, selective fXa inhibitor with pronounced in vitro anticoagulant activity. Moreover, 16g also displayed excellent in vivo antithrombotic activity in the rat venous thrombosis (VT) and arteriovenous shunt (AV-SHUNT) models. The bleeding risk evaluation showed that 16g had a safer profile than that of betrixaban at 1 mg/kg and 5 mg/kg dose. Additionally, 16g also exhibited satisfactory PK profiles. Eventually, 16g was selected to investigate its effect on hypoxia-reoxygenation- induced H9C2 cell viability. MTT results showed that H9C2 cell viability can be remarkably alleviated by 16g.

Predictors of thrombosis in testicular cancer during platinum-based chemotherapy

PURPOSE

To identify potential risk factors for the development of venous thromboembolic events in testicular cancer patients receiving platinum-based chemotherapy.

METHODS

We performed a retrospective analysis including 255 patients with testicular germ cell tumors who received platinum-based chemotherapy from 2003 to 2018 as a multi-center observational cohort study. Patient and tumor characteristics of patients with and without a thromboembolic event were analyzed.

RESULTS

49 (19%) patients experienced a venous thromboembolic event, with the majority representing pulmonary embolism and deep venous thrombosis (47%). There were no significant differences regarding the development of a venous thromboembolic event between first- and second-line regimes. Multivariate analysis showed an increased risk for a venous thromboembolic event in patients with clinical stage ≥ IIC disease (OR 2.259 [95% CI 1.105-4.618], p = 0.026), elevated serum LDH (OR 2.162 [95% CI 1.018-4.593], p = 0.045), febrile neutropenia (OR 2.973 [95% CI 1.363-6.487], p = 0.006) and central venous access (OR 3.465 [95% CI 1.068-11.243], p = 0.039). Patients suffering from a venous thromboembolic event revealed a significantly reduced overall survival (p = 0.033) during a median follow-up of 8 months [IQR 2-18].

CONCLUSIONS

19% of all patients treated by platinum-based chemotherapy due to testicular cancer suffered from a venous thromboembolic event, associated with reduced overall survival. As a result, monitoring of cancer patients at risk as well as the improvement of patients' awareness of a thromboembolic event should thus be the main goal of their treating physicians.

Rivaroxaban prescribing in a Saudi tertiary care teaching hospital

Purpose

This drug utilization review (DUR) aimed to describe the use of rivaroxaban in a tertiary care teaching hospital and to audit the hospital physicians’ prescribing practice.

Methods

This study reviewed rivaroxaban prescriptions for patients admitted to a tertiary care teaching hospital in Riyadh, Saudi Arabia, between October 1, 2016 and January 15, 2017. It included all in-patients who received at least one dose of rivaroxaban, using data from the hospital’s health information system (HIS). Appropriateness of prescribing was evaluated based on documented indication, dosing according to the patient’s renal function for each approved indication, and restriction policy as per hospital department.

Results

During the study period, a total of 343 rivaroxaban prescriptions for 322 patients were identified. Overall, more than 56% of rivaroxaban prescriptions met at least one inappropriate criterion. Inappropriate dosing per patient’s creatinine clearance (CrCl) was recognized in 42% of rivaroxaban prescriptions with the majority of these prescriptions issued for lower doses in 82.9% of prescriptions and non-approved indications identified in 14% of rivaroxaban prescriptions.

Conclusions

The introduction of oral rivaroxaban represents a paradigm shift in anticoagulation management. Future longer, larger multi-center research is needed to identify the most effective interventions to enhance rivaroxaban knowledge translation and reduce the likelihood of inappropriate rivaroxaban prescribing and associated economic and side effects sequelae.

Determination of rivaroxaban in patient's plasma samples by anti-Xa chromogenic test associated to High Performance Liquid Chromatography tandem Mass Spectrometry (HPLC-MS/MS)

Rivaroxaban is an oral direct factor Xa inhibitor, therapeutically indicated in the treatment of thromboembolic diseases. As other new oral anticoagulants, routine monitoring of rivaroxaban is not necessary, but important in some clinical circumstances. In our study a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was validated to measure rivaroxaban plasmatic concentration. Our method used a simple sample preparation, protein precipitation, and a fast chromatographic run. It was developed a precise and accurate method, with a linear range from 2 to 500 ng/mL, and a lower limit of quantification of 4 pg on column. The new method was compared to a reference method (anti-factor Xa activity) and both presented a good correlation (r = 0.98, p < 0.001). In addition, we validated hemolytic, icteric or lipemic plasma samples for rivaroxaban measurement by HPLC-MS/MS without interferences. The chromogenic and HPLC-MS/MS methods were highly correlated and should be used as clinical tools for drug monitoring. The method was applied successfully in a group of 49 real-life patients, which allowed an accurate determination of rivaroxaban in peak and trough levels.

Safety and effectiveness of rivaroxaban versus standard anticoagulation for the treatment of symptomatic deep vein thrombosis in routine clinical practice

In addition to parenteral anticoagulants and vitamin K antagonists (standard AC), non-vitamin K antagonist oral anticoagulants (NOAC) are increasingly being used for the acute and long-term treatment of deep vein thrombosis (DVT).

The international, prospective, non-interventional XALIA study compared the acute and long-term treatment of DVT with rivaroxaban or standard AC under routine clinical practice and confirmed the safety and efficacy of rivaroxaban demonstrated in Phase III studies: annual event rates for major bleeding, VTE and all-cause mortality were 1.2 %, 2.4 % and 0.8 % respectively, compared to 3.4 %, 3.9 %, and 6.2 % with standard AC.

The XALIA-DE subgroup analysis examined whether the XALIA results were applicable to Germany. The 586 rivaroxaban patients were younger and fewer had active cancer than the 355 treated with standard AC. As in XALIA, the incidence of major bleeding (1.6 vs. 4.1/100 patient-years [PY]), recurrent VTE (1.9 vs. 4.7/100 PY) and all-cause mortality (1.6 vs. 6.8/100 PY) were lower under rivaroxaban than under standard AC. These rates indicate a favourable benefit-risk profile of rivaroxaban under the conditions of everyday practice.

A novel nonsense mutation Tyr301* of PROS1 causing protein S deficiency

Hereditary protein S deficiency is one of the natural anticoagulant deficiency causing thrombophilia. Protein S deficiency is caused by a mutation in the PROS1 gene on 3q11.2 and is typically inherited in an autosomal dominant manner. We herein describe a Korean man with protein S deficiency from a novel nonsense mutation of PROS1. The patient was a 47-year-old man with deep-vein thrombosis. No relevant family history was documented. Coagulation test results included a significantly decreased protein S activity at 30%. Molecular genetic analysis targeting PROS1 on suspicion of hereditary protein S deficiency revealed that he was heterozygous for a novel transversion mutation, c.903C>G, in the exon 9 of PROS1. The mutation was predicted to result in premature termination at the codon 301 in the laminin G-type domain (p.Tyr301) of the protein (nonsense mutation). According to a review of the literature and database, the mutation described herein is the first substitution mutation affecting the codon 301 of PROS1.

Rivaroxaban postmarketing risk of liver injury

BACKGROUND & AIMS

Rivaroxaban is an oral direct factor Xa inhibitor that has been marketed worldwide since 2008 for the primary and secondary prevention and treatment of thromboembolic disorders. Although liver injury was observed in premarketing trials of rivaroxaban, there are no published postmarketing cases of liver injury associated with rivaroxaban.

METHODS

Report of 14 cases of liver injury associated with rivaroxaban, including two with liver biopsy, and search queries in three large international pharmacovigilance databases for comparable cases.

RESULTS

Formal causality assessment classified rivaroxaban as the "highly probable", "probable", and "possible" cause in 4, 7, and 3 patients, respectively. Search results from three large international pharmacovigilance databases revealed a considerable number of additional hepatic adverse events where rivaroxaban was reported as a suspected cause.

CONCLUSIONS

We interpret the presented information as a relevant safety signal that should be followed by pharmacoepidemiological studies in order to reliably estimate absolute and relative risks of liver injury associated with rivaroxaban in support of rational risk-benefit assessment. Meanwhile, incident symptoms and signs of liver disease in patients treated with rivaroxaban should be considered as a potential adverse drug reaction, and if no other likely cause can be identified rivaroxaban should be stopped as soon as possible.