Rivaroxaban

Uses and Indications

Xarelto and Rivaroxaban are indicated for various conditions related to thromboembolic events and cardiovascular risks.

Atrial Fibrillation

Both Xarelto and Rivaroxaban are indicated to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation.

Venous Thromboembolism (VTE)

These medications are indicated for the treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE). They are also indicated for the reduction in the risk of recurrence of DVT or PE. Additionally, they are indicated for the prophylaxis of DVT, which may lead to PE in patients undergoing knee or hip replacement surgery, and for prophylaxis of venous thromboembolism (VTE) in acutely ill medical patients.

Pediatric Indications

Xarelto and Rivaroxaban are indicated for the treatment of VTE and reduction in the risk of recurrent VTE in pediatric patients from birth to less than 18 years. They are also indicated for thromboprophylaxis in pediatric patients 2 years and older with congenital heart disease after the Fontan procedure.

Cardiovascular Indications

Both medications are indicated to reduce the risk of major cardiovascular events in patients with coronary artery disease (CAD) and to reduce the risk of major thrombotic vascular events in patients with peripheral artery disease (PAD), including those after recent lower extremity revascularization due to symptomatic PAD.

Limitations of Use

No teratogenic or nonteratogenic effects are mentioned for these medications.

Dosage and Administration

For nonvalvular atrial fibrillation, the recommended dosage is 15 mg or 20 mg taken orally once daily with food. For the treatment of deep vein thrombosis (DVT) and/or pulmonary embolism (PE), the initial dosage is 15 mg taken orally twice daily with food for the first 21 days, followed by 20 mg taken orally once daily with food for the remainder of the treatment period.

To reduce the risk of recurrence of DVT and/or PE in patients at continued risk, a dosage of 10 mg once daily is recommended, which can be taken with or without food, after at least 6 months of standard anticoagulant treatment. For prophylaxis of DVT following hip or knee replacement surgery, the dosage is 10 mg taken orally once daily, with or without food.

In acutely ill medical patients at risk for thromboembolic complications who are not at high risk of bleeding, the recommended dosage is 10 mg once daily, with or without food, during hospitalization and after discharge for a total duration of 31 to 39 days.

For patients with coronary artery disease (CAD) or peripheral artery disease (PAD), the dosage is 2.5 mg taken orally twice daily, with or without food, in combination with aspirin (75 to 100 mg) taken once daily.

For pediatric patients, specific dosing recommendations can be found in the Full Prescribing Information.

Rivaroxaban is available in various forms, including tablets, film-coated tablets, and granules for suspension. The oral suspension formulation requires reconstitution with 150 mL of purified water, yielding a suspension where 1 mL contains 1 mg of rivaroxaban. The reconstituted suspension should be discarded after the "Discard after" date indicated on the bottle.

Contraindications

Use of this medication is contraindicated in patients with active pathological bleeding and those with a severe hypersensitivity reaction to rivaroxaban or any of its formulations, including tablets and granules for suspension.

Warnings and Precautions

Risk of Bleeding Rivaroxaban can cause serious and fatal bleeding. An agent to reverse the activity of rivaroxaban is available.

Pregnancy-Related Hemorrhage Use rivaroxaban with caution in pregnant women due to the potential for obstetric hemorrhage and/or emergent delivery.

Prosthetic Heart Valves Rivaroxaban use is not recommended in patients with prosthetic heart valves.

Increased Risk of Thrombosis in Patients with Triple Positive Antiphospholipid Syndrome Rivaroxaban use is not recommended in patients with triple positive antiphospholipid syndrome.

Warnings

• Premature discontinuation of rivaroxaban increases the risk of thrombotic events. To reduce this risk, consider coverage with another anticoagulant if rivaroxaban is discontinued for a reason other than pathological bleeding or completion of a course of therapy.

• Epidural or spinal hematomas have occurred in patients treated with rivaroxaban who are receiving neuraxial anesthesia or undergoing spinal puncture. These hematomas may result in long-term or permanent paralysis.

Monitoring Requirements Monitor patients frequently for signs and symptoms of neurological impairment. If any impairment is observed, treat urgently. Consider the benefits and risks before neuraxial intervention in patients who are or who need to be anticoagulated.

General Precautions In clinical trials, the efficacy of rivaroxaban in elderly patients (65 years and older) was similar to that seen in younger patients. However, both thrombotic and bleeding event rates were higher in older patients.

Laboratory Tests No specific laboratory tests are mentioned for safe use.

Emergency Medical Help Instructions No specific instructions provided.

Stop Taking and Call Your Doctor Instructions No specific instructions provided.

Side Effects

The most common adverse reaction observed in adult patients treated with rivaroxaban is bleeding, occurring in more than 5% of cases. In pediatric patients, the incidence of bleeding is greater than 10%, along with other common adverse reactions such as cough, vomiting, and gastroenteritis.

Serious Adverse Reactions

• Risk of Bleeding: Rivaroxaban can cause serious and potentially fatal bleeding. An agent to reverse the activity of rivaroxaban is available.

• Premature Discontinuation: Discontinuation of rivaroxaban increases the risk of thrombotic events. It is recommended to consider coverage with another anticoagulant if rivaroxaban is discontinued for reasons other than pathological bleeding or completion of therapy.

• Spinal/Epidural Hematoma: Epidural or spinal hematomas have been reported in patients receiving rivaroxaban who are undergoing neuraxial anesthesia or spinal puncture. These hematomas may lead to long-term or permanent paralysis. Patients should be monitored for signs of neurological impairment and treated urgently if symptoms arise.

Clinical Trials Experience

In clinical trials, the most frequent adverse reactions leading to permanent drug discontinuation were bleeding events. For instance, in the ROCKET AF trial, the incidence of major bleeding was 3.6% for rivaroxaban compared to 3.5% for warfarin. Other notable findings include:

• Intracranial Hemorrhage: 0.5% for rivaroxaban versus 0.7% for warfarin.

• Gastrointestinal Bleeding: 2.0% for rivaroxaban versus 1.2% for warfarin.

• Fatal Bleeding: 0.2% for rivaroxaban versus 0.5% for warfarin.

Additional Adverse Reactions

Other adverse reactions reported in clinical trials and postmarketing experience include:

• Gastrointestinal Symptoms: Abdominal pain (2.7% in EINSTEIN DVT study), fatigue, back pain, dizziness, anxiety, depression, and insomnia, with varying incidence rates compared to enoxaparin/VKA.

• Hepatobiliary Disorders: Jaundice, cholestasis, and hepatitis.

• Immune System Disorders: Hypersensitivity reactions, including anaphylactic reactions and angioedema.

• Nervous System Disorders: Hemiparesis.

• Renal Disorders: Anticoagulant-related nephropathy.

• Respiratory Disorders: Eosinophilic pneumonia.

• Skin Reactions: Stevens-Johnson syndrome and drug reaction with eosinophilia and systemic symptoms (DRESS).

• Injury-Related Complications: Atraumatic splenic rupture.

Contraindications and Cautions

• Rivaroxaban is contraindicated in patients with active pathological bleeding and those with severe hypersensitivity reactions to the drug.

• Caution is advised when prescribing rivaroxaban to pregnant women due to the potential for obstetric hemorrhage and/or emergent delivery.

• The use of rivaroxaban is not recommended in patients with prosthetic heart valves or those with an increased risk of thrombosis, such as in triple positive antiphospholipid syndrome.

Overdosage

Overdose of rivaroxaban may lead to hemorrhage. In cases of overdose, rivaroxaban should be discontinued, and appropriate therapy should be initiated to manage any bleeding complications.

Drug Interactions

Rivaroxaban, available in various forms including tablets, film-coated tablets, and granules for suspension, has specific interaction considerations that healthcare providers should be aware of.

Pharmacokinetic Interactions

Rivaroxaban should not be used in conjunction with combined P-glycoprotein (P-gp) and strong CYP3A inhibitors or inducers. This is crucial as these interactions can significantly affect the pharmacokinetics of rivaroxaban, potentially leading to altered therapeutic effects or increased risk of adverse reactions.

Pharmacodynamic Interactions

Concomitant use of rivaroxaban with other anticoagulants is contraindicated. The combination of these agents can enhance the risk of bleeding complications, necessitating careful monitoring and consideration of alternative therapies.

In summary, healthcare professionals must avoid the use of rivaroxaban with strong P-gp and CYP3A inhibitors or inducers, as well as with other anticoagulants, to ensure patient safety and optimal therapeutic outcomes.

Pediatric Use

The safety and effectiveness of rivaroxaban (Xarelto) have been established in pediatric patients from birth to less than 18 years for the treatment of venous thromboembolism (VTE) and the reduction in the risk of recurrent VTE. This use is supported by evidence from adequate and well-controlled studies in adults, along with additional pharmacokinetic, safety, and efficacy data from a multicenter, prospective, open-label, active-controlled randomized study involving 500 pediatric patients.

Rivaroxaban has been shown to be effective in pediatric patients aged 2 years and older with congenital heart disease who have undergone the Fontan procedure. Clinical studies support the use of rivaroxaban tablets in dosages of 10 mg, 15 mg, and 20 mg. However, dosing cannot be reliably determined or recommended for children less than 6 months of age who were born at less than 37 weeks of gestation, had less than 10 days of oral feeding, or had a body weight of less than 2.6 kg.

Rivaroxaban 2.5 mg tablets are not recommended for use in pediatric patients due to a lack of safety, efficacy, pharmacokinetic, and pharmacodynamic data. Although not all adverse reactions identified in the adult population have been observed in clinical trials of children and adolescents, the same warnings and precautions applicable to adults should be considered for this population.

Geriatric Use

In clinical trials involving a total of 64,943 adult patients for the approved indications of rivaroxaban, 64 percent were aged 65 years and older, with 27 percent aged 75 years and older. The efficacy of rivaroxaban in elderly patients (65 years or older) was found to be similar to that observed in younger patients. However, it is important to note that both thrombotic and bleeding event rates were higher in the older patient population.

Healthcare professionals should exercise caution when prescribing rivaroxaban to geriatric patients, considering the increased risk of adverse events. Regular monitoring for signs of bleeding and thrombotic complications is recommended, and dose adjustments may be necessary based on individual patient factors, including renal function and concomitant medications.

Pregnancy

The limited available data on rivaroxaban in pregnant patients are insufficient to inform a drug-associated risk of adverse developmental outcomes. Rivaroxaban should be used with caution in this population due to the potential for pregnancy-related hemorrhage and/or emergent delivery. The anticoagulant effect of rivaroxaban cannot be reliably monitored with standard laboratory testing.

When prescribing rivaroxaban to pregnant patients, healthcare providers should carefully consider the benefits and risks for the mother, as well as the potential risks to the fetus. Adverse outcomes in pregnancy can occur regardless of the mother's health or medication use. The estimated background risk of major birth defects and miscarriage in the U.S. general population is approximately 2–4% and 15–20%, respectively, in clinically recognized pregnancies.

Pregnancy is a known risk factor for venous thromboembolism, with increased risk in women with inherited or acquired thrombophilias. Pregnant women with thromboembolic disease face heightened risks of maternal complications, including pre-eclampsia, as well as increased risks for intrauterine growth restriction, placental abruption, and early and late pregnancy loss.

Due to the pharmacologic activity of Factor Xa inhibitors and their potential to cross the placenta, there is a risk of bleeding occurring at any site in the fetus and/or neonate. All patients receiving anticoagulants, including pregnant women, are at risk for bleeding, which may be exacerbated during labor or delivery. The risk of bleeding should be balanced against the risk of thrombotic events when considering the use of rivaroxaban in this setting.

There are no adequate or well-controlled studies of rivaroxaban in pregnant women, and dosing for this population has not been established. Post-marketing experience is currently insufficient to determine a rivaroxaban-associated risk for major birth defects or miscarriage. In an in vitro placenta perfusion model, unbound rivaroxaban was rapidly transferred across the human placenta, and animal studies have shown that rivaroxaban crosses the placenta.

In pregnant rabbits, rivaroxaban has been associated with increased fetal toxicity, including increased resorptions, decreased number of live fetuses, and decreased fetal body weight when administered oral doses of ≥10 mg/kg during the period of organogenesis. This dose corresponds to approximately four times the human exposure of unbound drug based on AUC comparisons at the highest recommended human dose of 20 mg/day. Additionally, fetal body weights decreased in pregnant rats given oral doses of 120 mg/kg during the same period, corresponding to about fourteen times the human exposure of unbound drug. In rats, peripartal maternal bleeding and maternal and fetal death occurred at a rivaroxaban dose of 40 mg/kg, which is about six times the maximum human exposure of unbound drug at the human dose of 20 mg/day.

Lactation

Rivaroxaban has been detected in human milk, but there are insufficient data to determine its effects on breastfed infants or on milk production. The potential for excretion in breast milk should be considered when prescribing rivaroxaban to lactating mothers. In studies involving lactating rats, rivaroxaban and/or its metabolites were present in milk, with an estimated 2.1% of the maternal dose excreted within 32 hours following a single oral administration of 3 mg/kg.

Due to the lack of adequate or well-controlled studies in nursing mothers, dosing for breastfeeding women has not been established. Caution is advised when administering rivaroxaban to nursing mothers, as there may be potential adverse effects on the breastfed infant. Healthcare providers should counsel lactating mothers to monitor their infants for any signs of bleeding or other adverse effects. The developmental and health benefits of breastfeeding should be weighed against the mother's clinical need for rivaroxaban and any potential risks to the infant.

Renal Impairment

In patients with renal impairment, careful consideration is required when prescribing rivaroxaban. The drug is contraindicated in individuals with severe renal impairment, defined as a creatinine clearance (CrCl) of less than 30 mL/min. For those with moderate renal impairment (CrCl 30 to 49 mL/min), a reduced dose of rivaroxaban is recommended to mitigate the risk of increased exposure and potential bleeding complications.

Renal function should be assessed prior to initiating treatment with rivaroxaban and monitored periodically throughout the course of therapy, particularly in patients with any degree of renal impairment. It is essential to observe these patients closely for any signs or symptoms of bleeding, as they may be at an elevated risk. In cases where CrCl falls below 30 mL/min, rivaroxaban should not be used, and alternative anticoagulants should be considered.

In clinical studies, patients with CrCl values below 30 mL/min were excluded, and while pharmacokinetic data suggest that rivaroxaban exposure increases by approximately 44 to 64% in those with renal impairment, the safety and efficacy of rivaroxaban in this population remain uncertain. Therefore, it is crucial to exercise caution and adjust dosing as necessary based on renal function tests, ensuring that any changes in renal status are promptly addressed.

Hepatic Impairment

In patients with hepatic impairment, the use of rivaroxaban is subject to specific considerations based on the severity of liver dysfunction.

• Severe Hepatic Impairment (Child-Pugh Class C): Rivaroxaban is contraindicated in this population due to the lack of safety and pharmacokinetic data. The risk of bleeding is significantly increased in these patients.

• Moderate Hepatic Impairment (Child-Pugh Class B): The use of rivaroxaban is not recommended due to potential for increased exposure and heightened risk of bleeding. A pharmacokinetic study indicated that the area under the curve (AUC) increases by 127% in this group compared to healthy subjects.

• Mild Hepatic Impairment (Child-Pugh Class A): No dosage adjustment is necessary; however, caution is advised when prescribing rivaroxaban.

For all patients with hepatic impairment, liver function tests should be performed prior to initiating treatment and monitored periodically during therapy. Additionally, careful monitoring for signs and symptoms of bleeding is essential, as patients with hepatic impairment may be at an increased risk. The use of rivaroxaban is contraindicated in patients with any hepatic disease associated with coagulopathy.

No clinical data are available for pediatric patients with hepatic impairment.

Overdosage

In cases of overdose with rivaroxaban, there is a significant risk of hemorrhage. It is imperative to discontinue rivaroxaban immediately and initiate appropriate therapeutic measures if any bleeding complications arise. Notably, systemic exposure to rivaroxaban does not increase with single doses exceeding 50 mg due to its limited absorption characteristics.

The administration of activated charcoal may be considered to reduce absorption in the event of an overdose. However, due to rivaroxaban's high plasma protein binding, it is not amenable to dialysis. For patients experiencing anticoagulation-related complications, partial reversal of laboratory parameters may be achieved through the use of plasma products. Additionally, there exists a specific agent available to reverse the anti-factor Xa activity of rivaroxaban, which may be utilized in managing overdose situations.

Continuous monitoring of the patient is recommended to assess for any signs of bleeding or other complications associated with overdose.

Nonclinical Toxicology

Rivaroxaban was evaluated for its carcinogenic potential in long-term studies involving oral gavage administration to mice and rats for up to 2 years. The results indicated that rivaroxaban was not carcinogenic in either species. At the highest dose tested (60 mg/kg/day), systemic exposures (AUCs) of unbound rivaroxaban in male and female mice were found to be 1- and 2-times, respectively, the human exposure at a clinical dose of 20 mg/day. In male and female rats, systemic exposures at the same dose were 2- and 4-times, respectively, the human exposure.

In terms of mutagenicity, rivaroxaban demonstrated no mutagenic effects in bacterial assays (Ames test) and was not found to be clastogenic in V79 Chinese hamster lung cells in vitro or in the mouse micronucleus test in vivo.

Furthermore, studies assessing the potential for impairment of fertility revealed no adverse effects in male or female rats administered rivaroxaban at doses up to 200 mg/kg/day. This dose resulted in exposure levels, based on the unbound AUC, that were at least 13 times higher than those observed in humans receiving 20 mg of rivaroxaban daily.

Storage and Handling

Xarelto and Rivaroxaban are supplied in various forms, including tablets, film-coated tablets, and granules for suspension.

The products should be stored at room temperature between 20 °C to 25 °C (68 °F to 77 °F), with permissible excursions between 15 °C to 30 °C (59 °F to 86 °F) as per USP Controlled Room Temperature guidelines. It is important to keep the products out of the reach of children.

For the granules and reconstituted suspension, it is essential to discard any unused suspension after the "Discard after" date indicated on the bottle. Additionally, the granules and reconstituted suspension must not be frozen.

All products should be preserved in well-closed containers to maintain their integrity.