^ Pharmacodynamics
At recommended therapeutic doses, dabigatran etexilate prolongs the coagulation markers such as aPTT, ECT, TT, and dTT. INR is relatively insensitive to the exposure to dabigatran and cannot be interpreted the same way as used for warfarin monitoring.
^ Administration
PRADAXA Capsules should be swallowed whole. PRADAXA Capsules should be taken with a full glass of water. Breaking, chewing, or emptying the contents of the capsule can result in increased exposure [see Clinical Pharmacology (12.3)].
If a dose of PRADAXA Capsules is not taken at the scheduled time, the dose should be taken as soon as possible on the same day; the missed dose should be skipped if it cannot be taken at least 6 hours before the next scheduled dose. The dose of PRADAXA Capsules should not be doubled to make up for a missed dose.
Consider administration with food if gastrointestinal distress occurs with PRADAXA Capsules.
^ Thromboembolic And Bleeding Events In Patients With Prosthetic Heart Valves
The safety and efficacy of PRADAXA Capsules in adult patients with bileaflet mechanical prosthetic heart valves was evaluated in the RE-ALIGN trial, in which patients with bileaflet mechanical prosthetic heart valves (recently implanted or implanted more than three months prior to enrollment) were randomized to dose-adjusted warfarin or 150 mg, 220 mg, or 300 mg of PRADAXA Capsules twice a day. RE-ALIGN was terminated early due to the occurrence of significantly more thromboembolic events (valve thrombosis, stroke, transient ischemic attack, and myocardial infarction) and an excess of major bleeding (predominantly post-operative pericardial effusions requiring intervention for hemodynamic compromise) in the PRADAXA Capsules treatment arm as compared to the warfarin treatment arm. These bleeding and thromboembolic events were seen both in patients who were initiated on PRADAXA Capsules postoperatively within three days of mechanical bileaflet valve implantation, as well as in patients whose valves had been implanted more than three months prior to enrollment. Therefore, the use of PRADAXA is contraindicated in all patients with mechanical prosthetic valves [see Contraindications (4)].
The use of PRADAXA for the prophylaxis of thromboembolic events in patients with atrial fibrillation in the setting of other forms of valvular heart disease, including the presence of a bioprosthetic heart valve, has not been studied and is not recommended.
^ Patient Counseling Information
Advise the patient or caregiver to read the FDA-approved patient labeling (Medication Guide).
^ Description
The chemical name for dabigatran etexilate mesylate, a direct thrombin inhibitor, is β-Alanine, N-[[2-[[[4-[[[(hexyloxy)carbonyl]amino]iminomethyl] phenyl]amino]methyl]-1-methyl-1H-benzimidazol-5-yl]carbonyl]-N-2-pyridinyl-,ethyl ester, methanesulfonate. The empirical formula is C34H41N7O5 ∙ CH4O3S and the molecular weight is 723.86 (mesylate salt), 627.75 (free base). The structural formula is:
Dabigatran etexilate mesylate is a yellow-white to yellow powder. A saturated solution in pure water has a solubility of 1.8 mg/mL. It is freely soluble in methanol, slightly soluble in ethanol, and sparingly soluble in isopropanol.
PRADAXA Capsules are supplied in 75 mg, 110 mg, and 150 mg strengths for oral administration. Each capsule contains dabigatran etexilate mesylate as the active ingredient: 150 mg dabigatran etexilate (equivalent to 172.95 mg dabigatran etexilate mesylate), 110 mg dabigatran etexilate (equivalent to 126.83 mg dabigatran etexilate mesylate), or 75 mg dabigatran etexilate (equivalent to 86.48 mg dabigatran etexilate mesylate) along with the following inactive ingredients: acacia, dimethicone, hypromellose, hydroxypropyl cellulose, talc, and tartaric acid. The capsule shell is composed of carrageenan, hypromellose, potassium chloride, titanium dioxide, black edible ink, and FD&C Blue No. 2 (150 mg and 110 mg capsules only).
^ Treatment And Reduction In The Risk Of Recurrence Of Deep Venous Thrombosis And Pulmonary Embolism In Adult Patients
In the randomized, parallel group, double-blind trials, RE-COVER and RE-COVER II, patients with deep vein thrombosis and pulmonary embolism received PRADAXA Capsules 150 mg twice daily or warfarin (dosed to target INR of 2 to 3) following initial treatment with an approved parenteral anticoagulant for 5 to 10 days.
In RE-COVER, the median treatment duration during the oral only treatment period was 174 days. A total of 2,539 patients (30.9% patients with symptomatic PE with or without DVT and 68.9% with symptomatic DVT only) were treated with a mean age of 54.7 years. The patient population was 58.4% male, 94.8% white, 2.6% Asian, and 2.6% black. The concomitant diseases of patients in this trial included hypertension (35.9%), diabetes mellitus (8.3%), coronary artery disease (6.5%), active cancer (4.8%), and gastric or duodenal ulcer (4.4%). Concomitant medications included agents acting on renin-angiotensin system (25.2%), vasodilators (28.4%), serum lipid-reducing agents (18.2%), NSAIDs (21%), beta-blockers (14.8%), calcium channel blockers (8.5%), ASA (8.6%), and platelet inhibitors excluding ASA (0.6%). Patients randomized to warfarin had a mean percentage of time in the INR target range of 2.0 to 3.0 of 60% in RE-COVER study.
In RE-COVER II, the median treatment duration during the oral only treatment period was 174 days. A total of 2,568 patients (31.8% patients with symptomatic PE with or without DVT and 68.1% with symptomatic DVT only) were treated with a mean age of 54.9 years. The patient population was 60.6% male, 77.6% white, 20.9% Asian, and 1.5% black. The concomitant diseases of patients in this trial included hypertension (35.1%), diabetes mellitus (9.8%), coronary artery disease (7.1%), active cancer (3.9%), and gastric or duodenal ulcer (3.8%). Concomitant medications included agents acting on renin-angiotensin system (24.2%), vasodilators (28.6%), serum lipid-reducing agents (20.0%), NSAIDs (22.3%), beta-blockers (14.8%), calcium channel blockers (10.8%), ASA (9.8%), and platelet inhibitors excluding ASA (0.8%). Patients randomized to warfarin had a mean percentage of time in the INR target range of 2.0 to 3.0 of 57% in RE-COVER II study.
In studies RE-COVER and RE-COVER II, the protocol specified non-inferiority margin (2.75) for the hazard ratio was derived based on the upper limit of the 95% confidence interval of the historical warfarin effect. PRADAXA Capsules was demonstrated to be non-inferior to warfarin (dosed to target INR of 2 to 3) (Table 13) based on the primary composite endpoint (fatal PE or symptomatic non-fatal PE and/or DVT) and retains at least 66.9% (RE-COVER) and 63.9% (RE-COVER II) of the historical warfarin effect, respectively.
In the randomized, parallel-group, double-blind, pivotal trial, RE-MEDY, patients received PRADAXA Capsules 150 mg twice daily or warfarin (dosed to target INR of 2 to 3) following 3 to 12 months of treatment with anticoagulation therapy for an acute VTE. The median treatment duration during the treatment period was 534 days. A total of 2,856 patients were treated with a mean age of 54.6 years. The patient population was 61% male, and 90.1% white, 7.9% Asian and 2.0% black. The concomitant diseases of patients in this trial included hypertension (38.6%), diabetes mellitus (9.0%), coronary artery disease (7.2%), active cancer (4.2%), and gastric or duodenal ulcer (3.8%). Concomitant medications included agents acting on renin-angiotensin system (27.9%), vasodilators (26.7%), serum lipid reducing agents (20.6%), NSAIDs (18.3%), beta-blockers (16.3%), calcium channel blockers (11.1%), aspirin (7.7%), and platelet inhibitors excluding ASA (0.9%). Patients randomized to warfarin had a mean percentage of time in the INR target range of 2.0 to 3.0 of 62% in the study.
In study RE-MEDY, the protocol specified non-inferiority margin (2.85) for the hazard ratio was derived based on the point estimate of the historical warfarin effect. PRADAXA Capsules was demonstrated to be non-inferior to warfarin (dosed to target INR of 2 to 3) (Table 14) based on the primary composite endpoint (fatal PE or symptomatic non-fatal PE and/or DVT) and retains at least 63.0% of the historical warfarin effect. If the non-inferiority margin was derived based on the 50% retention of the upper limit of the 95% confidence interval, PRADAXA Capsules was demonstrated to retain at least 33.4% of the historical warfarin effect based on the composite primary endpoint.
In a randomized, parallel-group, double-blind, pivotal trial, RE-SONATE, patients received PRADAXA Capsules 150 mg twice daily or placebo following 6 to 18 months of treatment with anticoagulation therapy for an acute VTE. The median treatment duration was 182 days. A total of 1,343 patients were treated with a mean age of 55.8 years. The patient population was 55.5% male, 89.0% white, 9.3% Asian, and 1.7% black. The concomitant diseases of patients in this trial included hypertension (38.8%), diabetes mellitus (8.0%), coronary artery disease (6.0%), history of cancer (6.0%), gastric or duodenal ulcer (4.5%), and heart failure (4.6%). Concomitant medications included agents acting on renin-angiotensin system (28.7%), vasodilators (19.4%), beta-blockers (18.5%), serum lipid reducing agents (17.9%), NSAIDs (12.1%), calcium channel blockers (8.9%), aspirin (8.3%), and platelet inhibitors excluding ASA (0.7%). Based on the outcome of the primary composite endpoint (fatal PE, unexplained death, or symptomatic non-fatal PE and/or DVT), PRADAXA was superior to placebo (Table 15).
^ Converting From Or To Warfarin
When converting patients from warfarin therapy to PRADAXA Capsules, discontinue warfarin and start PRADAXA Capsules when the INR is below 2.0.
When converting from PRADAXA Capsules to warfarin, adjust the starting time of warfarin as follows:
^ Discontinuation For Surgery And Other Interventions
If possible, discontinue PRADAXA Capsules in adults 1 to 2 days (CrCl ≥ 50 mL/min) or 3 to 5 days (CrCl < 50 mL/min) before invasive or surgical procedures because of the increased risk of bleeding. Consider longer times for patients undergoing major surgery, spinal puncture, or placement of a spinal or epidural catheter or port, in whom complete hemostasis may be required [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3)].
For pediatric patients, discontinue PRADAXA Capsules 24 hours before an elective surgery (eGFR > 80 mL/min/1.73 m2) or 2 days before an elective surgery (eGFR 50-80 mL/min/1.73 m2). Pediatric patients with an eGFR <50 mL/min/1.73 m2 have not been studied, avoid use of PRADAXA Capsules in these patients.
If surgery cannot be delayed, there is an increased risk of bleeding [see Warnings and Precautions (5.2)]. This risk of bleeding should be weighed against the urgency of intervention [see Warnings and Precautions (5.1, 5.3)]. Use a specific reversal agent (idarucizumab) in case of emergency surgery or urgent procedures when reversal of the anticoagulant effect of dabigatran is needed in adults. Efficacy and safety of idarucizumab have not been established in pediatric patients [see Warnings and Precautions (5.2)]. Refer to the idarucizumab prescribing information for additional information. Restart PRADAXA Capsules as soon as medically appropriate.
^ Reduction In The Risk Of Recurrence Of Deep Venous Thrombosis And Pulmonary Embolism In Adult Patients
PRADAXA Capsules is indicated to reduce the risk of recurrence of deep venous thrombosis and pulmonary embolism in adult patients who have been previously treated.
^ Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reactions rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
^ Overdosage
Accidental overdose may lead to hemorrhagic complications. In the event of hemorrhagic complications, initiate appropriate clinical support, discontinue treatment with PRADAXA, and investigate the source of bleeding. A specific reversal agent (idarucizumab) is available for adult patients.
Dabigatran is primarily eliminated by the kidneys with a low plasma protein binding of approximately 35%. Hemodialysis can remove dabigatran; however, data supporting this approach are limited. Using a high-flux dialyzer, blood flow rate of 200 mL/min, and dialysate flow rate of 700 mL/min, approximately 49% of total dabigatran can be cleared from plasma over 4 hours. At the same dialysate flow rate, approximately 57% can be cleared using a dialyzer blood flow rate of 300 mL/min, with no appreciable increase in clearance observed at higher blood flow rates. Upon cessation of hemodialysis, a redistribution effect of approximately 7% to 15% is seen. The effect of dialysis on dabigatran's plasma concentration would be expected to vary based on patient specific characteristics. Measurement of aPTT or ECT may help guide therapy [see Warnings and Precautions (5.2) and Clinical Pharmacology (12.2)].
^ Reduction Of Risk Of Stroke And Systemic Embolism In Non-valvular Atrial Fibrillation In Adult Patients
PRADAXA Capsules is indicated to reduce the risk of stroke and systemic embolism in adult patients with non-valvular atrial fibrillation.
^ Converting From Or To Parenteral Anticoagulants
For adult and pediatric patients currently receiving a parenteral anticoagulant, start PRADAXA Capsules 0 to 2 hours before the time that the next dose of the parenteral drug was to have been administered or at the time of discontinuation of a continuously administered parenteral drug (e.g., intravenous unfractionated heparin).
For adult patients currently taking PRADAXA Capsules wait 12 hours (CrCl ≥ 30 mL/min) or 24 hours (CrCl < 30 mL/min) after the last dose of PRADAXA Capsules before initiating treatment with a parenteral anticoagulant [see Clinical Pharmacology (12.3)].
For pediatric patients currently taking PRADAXA, wait 12 hours after the last dose before switching to a parenteral anticoagulant.
^ Increased Risk Of Thrombotic Events After Premature Discontinuation
Premature discontinuation of any oral anticoagulant, including PRADAXA, in the absence of adequate alternative anticoagulation increases the risk of thrombotic events. If PRADAXA Capsules is discontinued for a reason other than pathological bleeding or completion of a course of therapy, consider coverage with another anticoagulant and restart PRADAXA Capsules as soon as medically appropriate [see Dosage and Administration (2.6, 2.7, 2.8)].
^ Prophylaxis Of Deep Vein Thrombosis And Pulmonary Embolism In Adult Patients Following Hip Replacement Surgery
In the randomized, parallel-group, double-blind, non-inferiority trials, RE-NOVATE and RE-NOVATE II patients received PRADAXA Capsules 75 mg orally 1-4 hours after surgery followed by 150 mg daily (RE-NOVATE), PRADAXA Capsules 110 mg orally 1-4 hours after surgery followed by 220 mg daily (RE-NOVATE and RE-NOVATE II) or subcutaneous enoxaparin 40 mg once daily initiated the evening before surgery (RE-NOVATE and RE-NOVATE II) for the prophylaxis of deep vein thrombosis and pulmonary embolism in patients who have undergone hip replacement surgery.
Overall, in RE-NOVATE and RE-NOVATE II, the median treatment duration was 33 days for PRADAXA Capsules and 33 days for enoxaparin. A total of 5,428 patients were treated with a mean age of 63.2 years. The patient population was 45.3% male, 96.1% white, 3.6% Asian, and 0.4 % black. The concomitant diseases of patients in these trials included hypertension (46.1%), venous insufficiency (15.4%), coronary artery disease (8.2%), diabetes mellitus (7.9%), reduced renal function (5.3%), heart failure (3.4%), gastric or duodenal ulcer (3.0%), VTE (2.7%), and malignancy (0.1%). Concomitant medications included cardiac therapy (69.7%), NSAIDs (68%), vasoprotectives (29.7%), agents acting on renin-angiotensin system (29.1%), beta-blockers (21.5%), diuretics (20.8%), lipid modifying agents (18.2%), any antithrombin/anticoagulant (16.0%), calcium channel blockers (13.6%), low molecular weight heparin (7.8%), aspirin (7.0%), platelet inhibitors excluding ASA (6.9%), other antihypertensives (6.7%), and peripheral vasodilators (2.6%).
For efficacy evaluation all patients were to have bilateral venography of the lower extremities at 3 days after last dose of study drug unless an endpoint event had occurred earlier in the study. In the primary efficacy analysis, PRADAXA Capsules 110 mg orally 1-4 hours after surgery followed by 220 mg daily was non-inferior to enoxaparin 40 mg once daily in a composite endpoint of confirmed VTE (proximal or distal DVT on venogram, confirmed symptomatic DVT, or confirmed PE) and all cause death during the treatment period (Tables 16 and 17). In the studies 2628 (76.5%) patients in RE-NOVATE and 1572 (78.9%) patients in RE-NOVATE II had evaluable venograms at study completion.
^3 Dosage Forms And Strengths
150 mg capsules with a light blue opaque cap imprinted in black with the Boehringer Ingelheim company symbol and a white opaque body imprinted in black with "R150".
110 mg capsules with a light blue opaque cap imprinted in black with the Boehringer Ingelheim company symbol and a light blue opaque body imprinted in black with "R110".
75 mg capsules with a white opaque cap imprinted in black with the Boehringer Ingelheim company symbol and a white opaque body imprinted in black with "R75".
^ Reduction Of Risk Of Stroke And Systemic Embolism In Non-valvular Atrial Fibrillation In Adult Patients
The concomitant use of PRADAXA with P-gp inducers (e.g., rifampin) reduces exposure to dabigatran and should generally be avoided [see Clinical Pharmacology (12.3)].
P-gp inhibition and impaired renal function are the major independent factors that result in increased exposure to dabigatran [see Clinical Pharmacology (12.3)]. Concomitant use of P-gp inhibitors in patients with renal impairment is expected to produce increased exposure of dabigatran compared to that seen with either factor alone.
In patients with moderate renal impairment (CrCl 30-50 mL/min), reduce the dosage of PRADAXA to 75 mg twice daily when administered concomitantly with the P-gp inhibitors dronedarone or systemic ketoconazole. The use of the P-gp inhibitors verapamil, amiodarone, quinidine, clarithromycin, and ticagrelor does not require a dosage adjustment of PRADAXA. These results should not be extrapolated to other P-gp inhibitors [see Warnings and Precautions (5.5), Use in Specific Populations (8.6), and Clinical Pharmacology (12.3)].
The concomitant use of PRADAXA and P-gp inhibitors in patients with severe renal impairment (CrCl 15-30 mL/min) should be avoided [see Warnings and Precautions (5.5), Use in Specific Populations (8.6), and Clinical Pharmacology (12.3)].
^ Pediatric Use
The safety and effectiveness of PRADAXA Capsules for the treatment and the reduction in risk of recurrence of venous thromboembolism have been established in pediatric patients 8 to less than 18 years of age. Use of PRADAXA for this indication is supported by evidence from adequate and well-controlled studies in pediatric patients. These studies included an open-label, randomized, parallel-group study and an open-label, single-arm safety study [see Adverse Reactions (6.1) and Clinical Studies (14.4, 14.5)]. Other age-appropriate pediatric dosage forms of dabigatran etexilate are available for pediatric patients less than 8 years of age for these indications.
Safety and effectiveness of PRADAXA Capsules have not been established in pediatric patients with non-valvular atrial fibrillation or those who have undergone hip replacement surgery.
^ Prophylaxis Of Deep Vein Thrombosis And Pulmonary Embolism In Adult Patients Following Hip Replacement Surgery
PRADAXA Capsules is indicated for the prophylaxis of deep vein thrombosis and pulmonary embolism in adult patients who have undergone hip replacement surgery.
^ Increased Risk Of Thrombosis In Patients With Triple-positive Antiphospholipid Syndrome
Direct-acting oral anticoagulants (DOACs), including PRADAXA, are not recommended for use in patients with triple-positive antiphospholipid syndrome (APS). For patients with APS (especially those who are triple-positive [positive for lupus anticoagulant, anticardiolipin, and anti-beta 2-glycoprotein I antibodies]), treatment with DOACs has been associated with increased rates of recurrent thrombotic events compared with vitamin K antagonist therapy.
^ Recommended Pradaxa Capsules Dosage For Pediatrics
PRADAXA Capsules can be used in pediatric patients aged 8 to less than 18 years of age who are able to swallow the capsules whole. Other age-appropriate pediatric dosage forms of dabigatran etexilate are available for pediatric patients less than 8 years of age. For the treatment of VTE in pediatric patients, initiate treatment following treatment with a parenteral anticoagulant for at least 5 days. For reduction in risk of recurrence of VTE, initiate treatment following previous treatment.
PRADAXA Capsules is dosed orally twice daily, one dose in the morning and one dose in the evening, at approximately the same time every day. The dosing interval should be as close to 12 hours as possible.
The recommended dosage of PRADAXA Capsules for the treatment of or reducing the risk of VTE in pediatric patients 8 to less than 18 years of age is based on the patient's actual weight as shown in Table 1 below. Administer PRADAXA twice daily. Adjust the dosage according to actual weight as treatment progresses [see Dosage and Administration (2.5)].
^4 Contraindications
PRADAXA is contraindicated in patients with:
^ Prophylaxis Of Deep Vein Thrombosis And Pulmonary Embolism In Adult Patients Following Hip Replacement Surgery
In patients with CrCl ≥ 50 mL/min who have concomitant administration of P-gp inhibitors such as dronedarone or systemic ketoconazole, it may be helpful to separate the timing of administration of PRADAXA and the P-gp inhibitor by several hours. The concomitant use of PRADAXA and P-gp inhibitors in patients with CrCl < 50 mL/min should be avoided [see Warnings and Precautions (5.5), Use in Specific Populations (8.6), and Clinical Pharmacology (12.2, 12.3)].
^ Postmarketing Experience
The following adverse reactions have been identified during post approval use of PRADAXA. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
Blood and Lymphatic System Disorders: Agranulocytosis, neutropenia, thrombocytopenia Gastrointestinal Disorders: Esophageal ulcer Immune System Disorders: Angioedema Renal and Urinary Disorders: Anticoagulant-related nephropathy Skin and Subcutaneous Tissue Disorders: Alopecia
^ How Supplied/storage And Handling
NDC: 63629-8242-1: 30 Capsules in a BOTTLE
^ Geriatric Use
Of the total number of patients in the RE-LY study, 82% were 65 and over, while 40% were 75 and over. The risk of stroke and bleeding increases with age, but the risk-benefit profile is favorable in all age groups [see Warnings and Precautions (5), Adverse Reactions (6.1), and Clinical Studies (14.1)].
^ Treatment And Reduction In Risk Of Recurrence Of Vte In Pediatric Patients
The concomitant use of PRADAXA with P-gp inhibitors has not been studied in pediatric patients but may increase exposure to dabigatran [see Warnings and Precautions (5.5)].
^ Treatment Of Vte In Pediatric Patients
The DIVERSITY study was conducted to demonstrate the efficacy and safety of PRADAXA compared to standard of care (SOC) for the treatment of venous thromboembolism (VTE) in pediatric patients from birth to less than 18 years of age. The study was designed as an open-label, randomized, parallel-group, non-inferiority study. Patients enrolled were randomized according to a 2:1 scheme to either an age-appropriate formulation (capsules, oral pellets, or oral solution) of PRADAXA (doses adjusted for age and weight) after at least 5 days and no longer than 21 days of treatment with a parenteral anticoagulant, or to SOC comprised of low molecular weight heparins (LMWH) or vitamin K antagonists (VKA) or fondaparinux. For patients on PRADAXA, drug concentration was determined prior to the 7th dose and a single titration was permitted to achieve drug target levels of 50-250 ng/mL. Inability to achieve target, after one up-titration, resulted in premature termination of study drug in 12 patients (6.8%).
The median treatment duration during the treatment period was 85 days. In total, 267 patients entered the study (leading index VTE was 64% deep vein thrombosis, 10% cerebral venous thrombosis or sinus thrombosis, and 9.0% pulmonary embolism), with 18% of patients having a central line-associated thrombosis. The patient population was 49.8% male, 91.8% white, 4.9% Asian, and 1.5% black; 168 patients were 12 to < 18 years old, 64 patients 2 to < 12 years, and 35 patients were younger than 2 years. The concomitant VTE-related risk factors of patients in this trial among study arms were as follows: inherited thrombophilia disorder (PRADAXA: 20%, SOC: 22%), congenital heart disease (PRADAXA: 12%, SOC: 30%), heart failure (PRADAXA: 3%, SOC: 18%), history of cancer (PRADAXA: 10%, SOC: 1%), CVL insertion (PRADAXA: 23%, SOC: 27%), immobility (PRADAXA: 13%, SOC: 10%) and significant infection (PRADAXA: 15%, SOC: 13%). The number of patients taking concomitant medications with hemostatic effects were similar in both treatment groups (PRADAXA: 15%, SOC: 16%).
The efficacy of PRADAXA was established based on a composite endpoint of patients with complete thrombus resolution, freedom from recurrent venous thromboembolic event, and freedom from mortality related to venous thromboembolic event (composite primary endpoint). Of the 267 randomized patients, 81 patients (45.8%) in the PRADAXA group and 38 patients (42.2%) in the SOC group met the criteria for the composite primary endpoint. The corresponding rate difference and 95% CI was -0.038 (-0.161, 0.086) and thus demonstrated non-inferiority of PRADAXA to SOC, since the upper bound of the 95% CI was lower than the predefined non-inferiority margin of 20% (see Table 18).
Subgroup analyses showed that there were no outliers in the treatment effect for the subgroups by age, sex, region, and presence of certain risk factors (central venous line, congenital heart disease, malignant disease). For the 3 different age strata, the proportions of patients that met the efficacy endpoint in the PRADAXA and SOC groups, respectively, were 13/22 (59.1%) and 7/13 (53.8%) for patients from birth to < 2 years [Rate Difference -0.052; (95%CI: -0.393, 0.288)], 21/43 (48.8%) and 12/21 (57.1%) for patients aged 2 to < 12 years [Rate Difference 0.083; (95%CI: -0.176, 0.342)], and 47/112 (42.0%) and 19/56 (33.9%) for patients aged 12 to < 18 years [Rate Difference -0.080; (95%CI: -0.234, 0.074)].
^ Spinal/epidural Anesthesia Or Puncture
When neuraxial anesthesia (spinal/epidural anesthesia) or spinal puncture is employed, patients treated with anticoagulant agents are at risk of developing an epidural or spinal hematoma which can result in long-term or permanent paralysis [see Boxed Warning].
To reduce the potential risk of bleeding associated with the concurrent use of PRADAXA and epidural or spinal anesthesia/analgesia or spinal puncture, consider the pharmacokinetic profile of dabigatran [see Clinical Pharmacology (12.3)]. Placement or removal of an epidural catheter or lumbar puncture is best performed when the anticoagulant effect of dabigatran is low; however, the exact timing to reach a sufficiently low anticoagulant effect in each patient is not known.
Should the physician decide to administer anticoagulation in the context of epidural or spinal anesthesia/analgesia or lumbar puncture, monitor frequently to detect any signs or symptoms of neurological impairment, such as midline back pain, sensory and motor deficits (numbness, tingling, or weakness in lower limbs), bowel and/or bladder dysfunction. Instruct patients to immediately report if they experience any of the above signs or symptoms. If signs or symptoms of spinal hematoma are suspected, initiate urgent diagnosis and treatment including consideration for spinal cord decompression even though such treatment may not prevent or reverse neurological sequelae.
^ Treatment Of Venous Thromboembolic Events In Pediatric Patients
PRADAXA Capsules is indicated for the treatment of venous thromboembolic events (VTE) in pediatric patients 8 to less than 18 years of age who have been treated with a parenteral anticoagulant for at least 5 days [see Dosage and Administration (2.3)].
^ Carcinogenesis, Mutagenesis, Impairment Of Fertility
Dabigatran was not carcinogenic when administered by oral gavage to mice and rats for up to 2 years. The highest doses tested (200 mg/kg/day) in mice and rats were approximately 3.6 and 6 times, respectively, the human exposure at MRHD of 300 mg/day based on AUC comparisons.
Dabigatran was not mutagenic in in vitro tests, including bacterial reversion tests, mouse lymphoma assay and chromosomal aberration assay in human lymphocytes, and the in vivo micronucleus assay in rats.
In the rat fertility study with oral gavage doses of 15, 70, and 200 mg/kg, males were treated for 29 days prior to mating, during mating up to scheduled termination, and females were treated 15 days prior to mating through gestation Day 6. No adverse effects on male or female fertility were observed at 200 mg/kg or 9 to 12 times the human exposure at MRHD of 300 mg/day based on AUC comparisons. However, the number of implantations decreased in females receiving 70 mg/kg, or 3 times the human exposure at MRHD based on AUC comparisons.
^ Effect Of P-gp Inducers And Inhibitors On Dabigatran Exposure
The concomitant use of PRADAXA with P-gp inducers (e.g., rifampin) reduces exposure to dabigatran and should generally be avoided [see Clinical Pharmacology (12.3)].
P-gp inhibition and impaired renal function are the major independent factors that result in increased exposure to dabigatran [see Clinical Pharmacology (12.3)]. Concomitant use of P-gp inhibitors in patients with renal impairment is expected to produce increased exposure of dabigatran compared to that seen with either factor alone.
^ Treatment And Reduction In The Risk Of Recurrence Of Deep Venous Thrombosis And Pulmonary Embolism In Adult Patients
Avoid use of PRADAXA and P-gp inhibitors in patients with CrCl < 50 mL/min [see Warnings and Precautions (5.5), Use in Specific Populations (8.6), and Clinical Pharmacology (12.3)].
^ Reduction Of Risk Of Stroke And Systemic Embolism In Non-valvular Atrial Fibrillation In Adult Patients
The clinical evidence for the efficacy of PRADAXA Capsules was derived from RE-LY (Randomized Evaluation of Long-term Anticoagulant Therapy), a multi-center, multi-national, randomized, parallel group trial comparing two blinded dosages of PRADAXA Capsules (110 mg twice daily and 150 mg twice daily) with open-label warfarin (dosed to target INR of 2 to 3) in patients with non-valvular, persistent, paroxysmal, or permanent atrial fibrillation and one or more of the following additional risk factors:
The primary objective of this study was to determine if PRADAXA Capsules was non-inferior to warfarin in reducing the occurrence of the composite endpoint, stroke (ischemic and hemorrhagic) and systemic embolism. The study was designed to ensure that PRADAXA Capsules preserved more than 50% of warfarin's effect as established by previous randomized, placebo-controlled trials of warfarin in atrial fibrillation. Statistical superiority was also analyzed.
A total of 18,113 patients were randomized and followed for a median of 2 years. The patients' mean age was 71.5 years and the mean CHADS2 score was 2.1. The patient population was 64% male, 70% Caucasian, 16% Asian, and 1% black. Twenty percent of patients had a history of a stroke or TIA and 50% were vitamin K antagonist (VKA) naïve, defined as less than 2 months total lifetime exposure to a VKA. Thirty-two percent of the population had never been exposed to a VKA. Concomitant diseases of patients in this trial included hypertension 79%, diabetes 23%, and CAD 28%. At baseline, 40% of patients were on aspirin and 6% were on clopidogrel. For patients randomized to warfarin, the mean percentage of time in therapeutic range (INR 2 to 3) was 64%.
Relative to warfarin and to PRADAXA Capsules 110 mg twice daily, PRADAXA Capsules 150 mg twice daily significantly reduced the primary composite endpoint of stroke and systemic embolism (see Table 11 and Figure 4).
Figure 4 Kaplan-Meier Curve Estimate of Time to First Stroke or Systemic Embolism
The contributions of the components of the composite endpoint, including stroke by subtype, are shown in Table 12. The treatment effect was primarily a reduction in stroke. PRADAXA Capsules 150 mg twice daily was superior in reducing ischemic and hemorrhagic strokes relative to warfarin.
In the RE-LY trial, the rate of all-cause mortality was lower on PRADAXA Capsules 150 mg than on warfarin (3.6% per year versus 4.1% per year). The rate of vascular death was lower on PRADAXA Capsules 150 mg compared to warfarin (2.3% per year versus 2.7% per year). Non-vascular death rates were similar in the treatment arms.
The efficacy of PRADAXA Capsules 150 mg twice daily was generally consistent across major subgroups (see Figure 5).
Figure 5 Stroke and Systemic Embolism Hazard Ratios by Baseline Characteristics*
* Randomized ITTNote: The figure above presents effects in various subgroups all of which are baseline characteristics and all of which were pre-specified. The 95% confidence limits that are shown do not take into account how many comparisons were made, nor do they reflect the effect of a particular factor after adjustment for all other factors. Apparent homogeneity or heterogeneity among groups should not be over-interpreted.
In RE-LY, a higher rate of clinical myocardial infarction was reported in patients who received PRADAXA Capsules (0.7 per 100 patient-years for 150 mg dose) than in those who received warfarin (0.6).
^ Reduction In The Risk Of Recurrence Of Venous Thromboembolic Events In Pediatric Patients
PRADAXA Capsules is indicated to reduce the risk of recurrence of VTE in pediatric patients 8 to less than 18 years of age who have been previously treated [see Dosage and Administration (2.3)].
^ Recommended Pradaxa Capsules Dosage For Adults
^ Reduction In The Risk Of Recurrence Of Vte In Pediatric Patients
Study 2 was an open-label, single-arm safety study to assess the safety of PRADAXA for the prevention of recurrent VTE in pediatric patients from birth to < 18 years. Patients who required further anticoagulation due to the presence of a clinical risk factor after completing the initial treatment for confirmed VTE (for at least 3 months) or after completing the DIVERSITY study were included in the study. Eligible patients received age- and weight adjusted dosages of an age-appropriate formulation (capsules or oral pellets) of PRADAXA until the clinical risk factor resolved, or up to a maximum of 12 months. The primary endpoints of the study included the recurrence of VTE, major and minor bleeding events, and mortality (overall and related to thrombotic or thromboembolic events) at 6 and 12 months.
Of the 214 patients in the study, 162 patients were 12 to < 18 years old, 43 patients were 2 to < 12 years old, and 9 patients were aged 6 months to < 2 years old.
The overall probability of being free from recurrence of VTE during the on-treatment period was 0.990 (95% CI: 0.960, 0.997) at 3 months, 0.984 (95% CI: 0.950, 0.995) at 6 months, and 0.984 (95% CI: 0.950, 0.995) at 12 months. The probability of being free from bleeding events during the on-treatment period was 0.849 (95% CI: 0.792, 0.891) at 3 months, 0.785 (95% CI: 0.718, 0.838) at 6 months, and 0.723 (95% CI: 0.645, 0.787) at 12 months. No on-treatment deaths occurred.
^6 Adverse Reactions
The following clinically significant adverse reactions are described elsewhere in the labeling:
The most serious adverse reactions reported with PRADAXA were related to bleeding [see Warnings and Precautions (5.2)].
^ Risk Of Bleeding
PRADAXA increases the risk of bleeding and can cause significant and, sometimes, fatal bleeding. Promptly evaluate any signs or symptoms of blood loss (e.g., a drop in hemoglobin and/or hematocrit or hypotension). Discontinue PRADAXA Capsules in patients with active pathological bleeding [see Dosage and Administration (2.4)].
Risk factors for bleeding include the concomitant use of other drugs that increase the risk of bleeding (e.g., anti-platelet agents, heparin, fibrinolytic therapy, and chronic use of NSAIDs). PRADAXA's anticoagulant activity and half-life are increased in patients with renal impairment [see Clinical Pharmacology (12.2)].
^ Females And Males Of Reproductive Potential
Females of reproductive potential requiring anticoagulation should discuss pregnancy planning with their physician.
The risk of clinically significant uterine bleeding, potentially requiring gynecological surgical interventions, identified with oral anticoagulants including PRADAXA should be assessed in females of reproductive potential and those with abnormal uterine bleeding.
^ Pharmacokinetics
Dabigatran etexilate mesylate is absorbed as the dabigatran etexilate ester. The ester is then hydrolyzed, forming dabigatran, the active moiety. Dabigatran is metabolized to four different acyl glucuronides and both the glucuronides and dabigatran have similar pharmacological activity. Pharmacokinetics described here refer to the sum of dabigatran and its glucuronides. Dabigatran displays dose-proportional pharmacokinetics in healthy adult subjects and adult patients in the range of doses from 10 to 400 mg. Given twice daily, dabigatran's accumulation factor in adults and pediatrics is approximately two.
^ Important Dosage Information
Dabigatran etexilate is available in different dosage forms and not all dosage forms are approved for the same indications and age groups. In addition, there are differences between the dosage forms with respect to dosing due to differences in bioavailability. Do not substitute different dosage forms on a milligram-to-milligram basis and do not combine more than one dosage form to achieve the total dose [see Clinical Pharmacology (12.3)].
^ Treatment Of Deep Venous Thrombosis And Pulmonary Embolism In Adult Patients
PRADAXA Capsules is indicated for the treatment of deep venous thrombosis and pulmonary embolism in adult patients who have been treated with a parenteral anticoagulant for 5-10 days.
^ Mechanism Of Action
Dabigatran and its acyl glucuronides are competitive, direct thrombin inhibitors. Because thrombin (serine protease) enables the conversion of fibrinogen into fibrin during the coagulation cascade, its inhibition prevents the development of a thrombus. Both free and clot-bound thrombin, and thrombin-induced platelet aggregation are inhibited by the active moieties.