Clinical Pharmacology for Eliquis
Mechanism Of Action
Apixaban is a selective inhibitor of FXa. It does not require antithrombin III for antithrombotic activity. Apixaban inhibits free and clot-bound FXa, and prothrombinase activity. Apixaban has no direct effect on platelet aggregation, but indirectly inhibits platelet aggregation induced by thrombin. By inhibiting FXa, apixaban decreases thrombin generation and thrombus development.
Pharmacodynamics
As a result of FXa inhibition, apixaban prolongs clotting tests such as prothrombin time (PT), INR, and activated partial thromboplastin time (aPTT). Changes observed in these clotting tests at the expected therapeutic dose, however, are small, subject to a high degree of variability, and not useful in monitoring the anticoagulation effect of apixaban.
The Rotachrom® Heparin chromogenic assay was used to measure the effect of apixaban on FXa activity in humans primarily during the apixaban adult development program. A concentrationdependent increase in anti-FXa activity was observed in the dose range tested and was similar in healthy subjects and patients with AF.
This test is not recommended for assessing the anticoagulant effect of apixaban.
Effect Of PCCs On Pharmacodynamics Of ELIQUIS
There is no clinical experience to reverse bleeding with the use of 4-factor PCC products in individuals who have received ELIQUIS.
Effects of 4-factor PCCs on the pharmacodynamics of apixaban were studied in healthy subjects.
Following administration of apixaban dosed to steady state, endogenous thrombin potential (ETP) returned to pre-apixaban levels 4 hours after the initiation of a 30-minute PCC infusion, compared to 45 hours with placebo. Mean ETP levels continued to increase and exceeded pre-apixaban levels reaching a maximum (34%-51% increase over pre-apixaban levels) at 21 hours after initiating PCC and remained elevated (21%-27% increase) at the end of the study (69 hours after initiation of PCC). The clinical relevance of this increase in ETP is unknown.
Pharmacodynamic Drug Interaction Studies
Pharmacodynamic drug interaction studies with aspirin, clopidogrel, aspirin and clopidogrel, prasugrel, enoxaparin, and naproxen were conducted. No pharmacodynamic interactions were observed with aspirin, clopidogrel, or prasugrel [see WARNINGS AND PRECAUTIONS]. A 50% to 60% increase in anti-FXa activity was observed when ELIQUIS was coadministered with enoxaparin or naproxen.
Specific Populations
Renal Impairment
Anti-FXa activity adjusted for exposure to apixaban was similar across renal function categories.
Hepatic Pmpairment
Changes in anti-FXa activity were similar in patients with mild-to-moderate hepatic impairment and healthy subjects. However, in patients with moderate hepatic impairment, there is no clear understanding of the impact of this degree of hepatic function impairment on the coagulation cascade and its relationship to efficacy and bleeding. Patients with severe hepatic impairment were not studied.
Pediatric Patients
In pediatric patients treated with apixaban, the correlation between anti-FXa activity and plasma concentration is linear with a slope close to 1.
Cardiac Electrophysiology
Apixaban has no effect on the QTc interval in humans at doses up to 50 mg.
Pharmacokinetics
Apixaban demonstrates linear pharmacokinetics with dose-proportional increases in exposure for oral doses up to 10 mg.
Absorption
The absolute bioavailability of apixaban is approximately 50% for doses up to 10 mg of ELIQUIS. Food does not affect the bioavailability of apixaban. Maximum concentrations (Cmax) of apixaban appear 3 to 4 hours after oral administration of ELIQUIS. At doses≥25 mg, apixaban displays dissolution-limited absorption with decreased bioavailability. Following oral administration of 10 mg of apixaban as 2 crushed 5 mg tablets suspended in 30 mL of water, exposure was similar to that after oral administration of 2 intact 5 mg tablets. Following oral administration of 10 mg of apixaban as 2 crushed 5 mg tablets mixed with 30 g of applesauce, the Cmax and AUC were 20% and 16% lower, respectively, when compared to administration of 2 intact 5 mg tablets. Following administration of a crushed 5 mg ELIQUIS tablet that was suspended in 60 mL D5W and delivered through a nasogastric tube, exposure was similar to that seen in other clinical trials involving healthy volunteers receiving a single oral 5 mg tablet dose.
Distribution
Plasma protein binding in humans is approximately 87%. The volume of distribution (Vss) is approximately 21 liters.
Metabolism
Approximately 25% of an orally administered apixaban dose is recovered in urine and feces as metabolites. Apixaban is metabolized mainly via CYP3A4 with minor contributions from CYP1A2, 2C8, 2C9, 2C19, and 2J2. O-demethylation and hydroxylation at the 3-oxopiperidinyl moiety are the major sites of biotransformation.
Unchanged apixaban is the major drug-related component in human plasma; there are no active circulating metabolites.
Elimination
Apixaban is eliminated in both urine and feces. Renal excretion accounts for about 27% of total clearance. Biliary and direct intestinal excretion contributes to elimination of apixaban in the feces.
Apixaban has a total clearance of approximately 3.3 L/hour and an apparent half-life of approximately 12 hours following oral administration.
Apixaban is a substrate of transport proteins: P-gp and breast cancer resistance protein.
Drug Interaction Studies
In in vitro apixaban studies at concentrations significantly greater than therapeutic exposures, no inhibitory effect on the activity of CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2D6, CYP3A4/5, or CYP2C19, nor induction effect on the activity of CYP1A2, CYP2B6, or CYP3A4/5 were observed. Therefore, apixaban is not expected to alter the metabolic clearance of coadministered drugs that are metabolized by these enzymes. Apixaban is not a significant inhibitor of P-gp.
The effects of coadministered drugs on the pharmacokinetics of apixaban are summarized in Figure 2 [see WARNINGS AND PRECAUTIONS and DRUG INTERACTIONS].
Figure 2: Effect of Coadministered Drugs on the Pharmacokinetics of Apixaban
In dedicated studies conducted in healthy subjects, famotidine, atenolol, prasugrel, and enoxaparin did not meaningfully alter the pharmacokinetics of apixaban.
In studies conducted in healthy subjects, apixaban did not meaningfully alter the pharmacokinetics of digoxin, naproxen, atenolol, prasugrel, or acetylsalicylic acid.
Specific Populations
The effects of level of renal impairment, age, body weight, and level of hepatic impairment on the pharmacokinetics of apixaban are summarized in Figure 3.
Figure 3: Effect of Specific Populations on the Pharmacokinetics of Apixaban
 |
* ESRD subjects treated with intermittent hemodialysis; reported PK findings are following single dose of apixaban posthemodialysis.
† Results reflect CrCl of 15 mL/min based on regression analysis.
‡ Dashed vertical lines illustrate pharmacokinetic changes that were used to inform dosing recommendations.
§ No dose adjustment is recommended for nonvalvular atrial fibrillation patients unless at least 2 of the following patient characteristics (age greater than or equal to 80 years, body weight less than or equal to 60 kg, or serum creatinine greater than or equal to 1.5 mg/dL) are present. |
Gender
A study in healthy subjects comparing the pharmacokinetics in males and females showed no meaningful difference.
Race
The results across pharmacokinetic studies in normal subjects showed no differences in apixaban pharmacokinetics among White/Caucasian, Asian, and Black/African American subjects. No dose adjustment is required based on race/ethnicity.
Hemodialysis In ESRD Subjects
Systemic exposure to apixaban administered as a single 5 mg dose in ESRD subjects dosed immediately after the completion of a 4-hour hemodialysis session (postdialysis) is 36% higher when compared to subjects with normal renal function (Figure 3). The systemic exposure to apixaban administered 2 hours prior to a 4-hour hemodialysis session with a dialysate flow rate of 500 mL/min and a blood flow rate in the range of 350 to 500 mL/min is 17% higher compared to those with normal renal function. The dialysis clearance of apixaban is approximately 18 mL/min. The systemic exposure of apixaban is 14% lower on dialysis when compared to not on dialysis.
Protein binding was similar (92%-94%) between healthy controls and ESRD subjects during the on-dialysis and off-dialysis periods.
Pediatric Patients
Apixaban reached maximum concentration (Cmax) in pediatric patients approximately 2 hours after single-dose administration. In pediatric patients, apixaban has a total apparent clearance of about 3.0 L/h.
An exploratory analysis in pediatric patients did not reveal relevant differences in apixaban exposure based on gender or race.
Clinical Studies
Reduction Of Risk Of Stroke And Systemic Embolism In Nonvalvular Atrial Fibrillation
ARISTOTLE
Evidence for the efficacy and safety of ELIQUIS was derived from ARISTOTLE, a multinational, double-blind study in patients with nonvalvular AF comparing the effects of ELIQUIS and warfarin on the risk of stroke and non-central nervous system (CNS) systemic embolism. In ARISTOTLE, patients were randomized to ELIQUIS 5 mg orally twice daily (or 2.5 mg twice daily in subjects with at least 2 of the following characteristics: age greater than or equal to 80 years, body weight less than or equal to 60 kg, or serum creatinine greater than or equal to 1.5 mg/dL) or to warfarin (targeted to an INR range of 2.0-3.0). Patients had to have one or more of the following additional risk factors for stroke:
- prior stroke or transient ischemic attack (TIA)
- prior systemic embolism
- age greater than or equal to 75 years
- arterial hypertension requiring treatment
- diabetes mellitus
- heart failure≥New York Heart Association Class 2
- left ventricular ejection fraction ≤40%
The primary objective of ARISTOTLE was to determine whether ELIQUIS 5 mg twice daily (or 2.5 mg twice daily) was effective (noninferior to warfarin) in reducing the risk of stroke (ischemic or hemorrhagic) and systemic embolism. Superiority of ELIQUIS to warfarin was also examined for the primary endpoint (rate of stroke and systemic embolism), major bleeding, and death from any cause.
A total of 18,201 patients were randomized and followed on study treatment for a median of 89 weeks. Forty-three percent of patients were vitamin K antagonist (VKA) “naive,” defined as having received ≤30 consecutive days of treatment with warfarin or another VKA before entering the study. The mean age was 69 years and the mean CHADS2 score (a scale from 0 to 6 used to estimate risk of stroke, with higher scores predicting greater risk) was 2.1. The population was 65% male, 83% Caucasian, 14% Asian, and 1% Black. There was a history of stroke, TIA, or non- CNS systemic embolism in 19% of patients. Concomitant diseases of patients in this study included hypertension 88%, diabetes 25%, congestive heart failure (or left ventricular ejection fraction ≤40%) 35%, and prior myocardial infarction 14%. Patients treated with warfarin in ARISTOTLE had a mean percentage of time in therapeutic range (INR 2.0-3.0) of 62%.
ELIQUIS was superior to warfarin for the primary endpoint of reducing the risk of stroke and systemic embolism (Table 13 and Figure 4). Superiority to warfarin was primarily attributable to a reduction in hemorrhagic stroke and ischemic strokes with hemorrhagic conversion compared to warfarin. Purely ischemic strokes occurred with similar rates on both drugs.
ELIQUIS also showed significantly fewer major bleeds than warfarin [see ADVERSE REACTIONS].
Table 13: Key Efficacy Outcomes in Patients with Nonvalvular Atrial Fibrillation in ARISTOTLE (Intent-to-Treat Analysis)
|
ELIQUIS
N=9120
n (%/year) |
Warfarin
N=9081
n (%/year) |
Hazard Ratio
(95% CI) |
P-value |
| Stroke or systemic embolism |
212 (1.27) |
265 (1.60) |
0.79 (0.66, 0.95) |
0.01 |
| Stroke |
199 (1.19) |
250 (1.51) |
0.79 (0.65, 0.95) |
|
| Ischemic without hemorrhage |
140 (0.83) |
136 (0.82) |
1.02 (0.81, 1.29) |
|
| Ischemic with hemorrhagic conversion |
12 (0.07) |
20 (0.12) |
0.60 (0.29, 1.23) |
|
| Hemorrhagic |
40 (0.24) |
78 (0.47) |
0.51 (0.35, 0.75) |
|
| Unknown |
14 (0.08) |
21 (0.13) |
0.65 (0.33, 1.29) |
|
| Systemic embolism |
15 (0.09) |
17 (0.10) |
0.87 (0.44, 1.75) |
|
| The primary endpoint was based on the time to first event (one per subject). Component counts are for subjects with any event, not necessarily the first. |
Figure 4: Kaplan-Meier Estimate of Time to First Stroke or Systemic Embolism in ARISTOTLE (Intent-to-Treat Population)
All-cause death was assessed using a sequential testing strategy that allowed testing for superiority if effects on earlier endpoints (stroke plus systemic embolus and major bleeding) were demonstrated. ELIQUIS treatment resulted in a significantly lower rate of all-cause death (p = 0.046) than did treatment with warfarin, primarily because of a reduction in cardiovascular death, particularly stroke deaths. Non-vascular death rates were similar in the treatment arms.
In ARISTOTLE, the results for the primary efficacy endpoint were generally consistent across most major subgroups including weight, CHADS2 score (a scale from 0 to 6 used to predict risk of stroke in patients with AF, with higher scores predicting greater risk), prior warfarin use, level of renal impairment, geographic region, and aspirin use at randomization (Figure 5).
Figure 5: Stroke and Systemic Embolism Hazard Ratios by Baseline Characteristics – ARISTOTLE Study
 |
| Note: The figure above presents effects in various subgroups, all of which are baseline characteristics and all of which were prespecified, if not the groupings. 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. |
At the end of the ARISTOTLE study, warfarin patients who completed the study were generally maintained on a VKA with no interruption of anticoagulation. ELIQUIS patients who completed the study were generally switched to a VKA with a 2-day period of coadministration of ELIQUIS and VKA, so that some patients may not have been adequately anticoagulated after stopping ELIQUIS until attaining a stable and therapeutic INR. During the 30 days following the end of the study, there were 21 stroke or systemic embolism events in the 6791 patients (0.3%) in the ELIQUIS arm compared to 5 in the 6569 patients (0.1%) in the warfarin arm [see DOSAGE AND ADMINISTRATION].
AVERROES
In AVERROES, patients with nonvalvular atrial fibrillation thought not to be candidates for warfarin therapy were randomized to treatment with ELIQUIS 5 mg orally twice daily (or 2.5 mg twice daily in selected patients) or aspirin 81 to 324 mg once daily. The primary objective of the study was to determine if ELIQUIS was superior to aspirin for preventing the composite outcome of stroke or systemic embolism. AVERROES was stopped early on the basis of a prespecified interim analysis showing a significant reduction in stroke and systemic embolism for ELIQUIS compared to aspirin that was associated with a modest increase in major bleeding (Table 14) [see ADVERSE REACTIONS ].
Table 14: Key Efficacy Outcomes in Patients with Nonvalvular Atrial Fibrillation in AVERROES
|
ELIQUIS
N=2807
n (%/year) |
Aspirin
N=2791
n (%/year) |
Hazard Ratio
(95% CI) |
P-value |
| Stroke or systemic embolism |
51 (1.62) |
113 (3.63) |
0.45 (0.32, 0.62) |
<0.0001 |
| Stroke |
|
|
|
|
| Ischemic or undetermined |
43 (1.37) |
97 (3.11) |
0.44 (0.31, 0.63) |
- |
| Hemorrhagic |
6 (0.19) |
9 (0.28) |
0.67 (0.24, 1.88) |
- |
| Systemic embolism |
2 (0.06) |
13 (0.41) |
0.15 (0.03, 0.68) |
- |
| MI |
24 (0.76) |
28 (0.89) |
0.86 (0.50, 1.48) |
- |
| All-cause death |
111 (3.51) |
140 (4.42) |
0.79 (0.62, 1.02) |
0.068 |
| Vascular death |
84 (2.65) |
96 (3.03) |
0.87 (0.65, 1.17) |
- |
Prophylaxis Of Deep Vein Thrombosis Following Hip Or Knee Replacement Surgery
The clinical evidence for the effectiveness of ELIQUIS is derived from the ADVANCE-1, ADVANCE-2, and ADVANCE-3 clinical trials in adult patients undergoing elective hip (ADVANCE-3) or knee (ADVANCE-2 and ADVANCE-1) replacement surgery. A total of 11,659 patients were randomized in 3 double-blind, multi-national studies. Included in this total were 1866 patients age 75 or older, 1161 patients with low body weight (≤60 kg), 2528 patients with Body Mass Index≥33 kg/m2, and 625 patients with severe or moderate renal impairment.
In the ADVANCE-3 study, 5407 patients undergoing elective hip replacement surgery were randomized to receive either ELIQUIS 2.5 mg orally twice daily or enoxaparin 40 mg subcutaneously once daily. The first dose of ELIQUIS was given 12 to 24 hours post surgery, whereas enoxaparin was started 9 to 15 hours prior to surgery. Treatment duration was 32 to 38 days.
In patients undergoing elective knee replacement surgery, ELIQUIS 2.5 mg orally twice daily was compared to enoxaparin 40 mg subcutaneously once daily (ADVANCE-2, N=3057) or enoxaparin 30 mg subcutaneously every 12 hours (ADVANCE-1, N=3195). In the ADVANCE-2 study, the first dose of ELIQUIS was given 12 to 24 hours postsurgery, whereas enoxaparin was started 9 to 15 hours prior to surgery. In the ADVANCE-1 study, both ELIQUIS and enoxaparin were initiated 12 to 24 hours post surgery. Treatment duration in both ADVANCE-2 and ADVANCE-1 was 10 to 14 days.
In all 3 studies, the primary endpoint was a composite of adjudicated asymptomatic and symptomatic DVT, nonfatal PE, and all-cause death at the end of the double-blind intended treatment period. In ADVANCE-3 and ADVANCE-2, the primary endpoint was tested for noninferiority, then superiority, of ELIQUIS to enoxaparin. In ADVANCE-1, the primary endpoint was tested for noninferiority of ELIQUIS to enoxaparin.
The efficacy data are provided in Tables 15 and 16.
Table 15: Summary of Key Efficacy Analysis Results During the Intended Treatment Period for Patients Undergoing Elective Hip Replacement Surgery*
| Events During 35-Day Treatment Period |
ADVANCE-3 |
|
ELIQUIS
2.5 mg po bid |
Enoxaparin
40 mg sc qd |
Relative Risk
(95% CI)
P-value |
| Number of Patients |
N=1949 |
N=1917 |
|
| Total VTE†/All-cause death |
27 (1.39%)
(0.95, 2.02) |
74 (3.86%)
(3.08, 4.83) |
0.36
(0.22, 0.54)
p<0.0001 |
| Number of Patients |
N=2708 |
N=2699 |
|
| All-cause death |
3 (0.11%)
(0.02, 0.35) |
1 (0.04%)
(0.00, 0.24) |
|
| PE |
3 (0.11%)
(0.02, 0.35) |
5 (0.19%)
(0.07, 0.45) |
|
| Symptomatic DVT |
1 (0.04%)
(0.00, 0.24) |
5 (0.19%)
(0.07, 0.45) |
|
| Number of Patients |
N=2196 |
N=2190 |
|
| Proximal DVT‡ |
7 (0.32%)
(0.14, 0.68) |
20 (0.91%)
(0.59, 1.42) |
|
| Number of Patients |
N=1951 |
N=1908 |
|
| Distal DVT‡ |
20 (1.03%)
(0.66, 1.59) |
57 (2.99%)
(2.31, 3.86) |
|
* Events associated with each endpoint were counted once per subject but subjects may have contributed events to multiple endpoints.
† Total VTE includes symptomatic and asymptomatic DVT and PE.
‡ Includes symptomatic and asymptomatic DVT. |
Table 16: Summary of Key Efficacy Analysis Results During the Intended Treatment Period for Patients Undergoing Elective Knee Replacement Surgery*
|
ADVANCE-1 |
ADVANCE-2 |
Events during
12-day treatment period |
ELIQUIS
2.5 mg po
bid |
Enoxaparin
30 mg sc
q12h |
Relative Risk
(95% CI)
P-value |
ELIQUIS
2.5 mg po bid |
Enoxaparin
40 mg sc
qd |
Relative Risk
(95% CI)
P-value |
| Number of Patients |
N=1157 |
N=1130 |
|
N=976 |
N=997 |
|
| Total VTE†/All cause death |
104 (8.99%)
(7.47, 10.79) |
100 (8.85%)
(7.33, 10.66) |
1.02
(0.78, 1.32)
NS |
147 (15.06%)
(12.95, 17.46) |
243 (24.37%)
(21.81, 27.14) |
0.62
(0.51, 0.74)
p<0.0001 |
| Number of Patients |
N=1599 |
N=1596 |
|
N=1528 |
N=1529 |
|
| All-cause death |
3 (0.19%)
(0.04, 0.59) |
3 (0.19%)
(0.04, 0.59) |
|
2 (0.13%)
(0.01, 0.52) |
0 (0%)
(0.00, 0.31) |
|
| PE |
16 (1.0%)
(0.61, 1.64) |
7 (0.44%)
(0.20, 0.93) |
|
4 (0.26%)
(0.08, 0.70) |
0 (0%)
(0.00, 0.31) |
|
| Symptomatic DVT |
3 (0.19%)
(0.04, 0.59) |
7 (0.44%)
(0.20, 0.93) |
|
3 (0.20%)
(0.04, 0.61) |
7 (0.46%)
(0.20, 0.97) |
|
| Number of Patients |
N=1254 |
N=1207 |
|
N=1192 |
N=1199 |
|
| Proximal DVT‡ |
9 (0.72%)
(0.36, 1.39) |
11 (0.91%)
(0.49, 1.65) |
|
9 (0.76%)
(0.38, 1.46) |
26 (2.17%)
(1.47, 3.18) |
|
| Number of Patients |
N=1146 |
N=1133 |
|
N=978 |
N=1000 |
|
| Distal DVT‡ |
83 (7.24%)
(5.88, 8.91) |
91 (8.03%)
(6.58, 9.78) |
|
142 (14.52%)
(12.45, 16.88) |
239 (23.9%)
(21.36, 26.65) |
|
* Events associated with each endpoint were counted once per subject but subjects may have contributed events to multiple endpoints.
† Total VTE includes symptomatic and asymptomatic DVT and PE.
‡ Includes symptomatic and asymptomatic DVT. |
The efficacy profile of ELIQUIS was generally consistent across subgroups of interest for this indication (e.g., age, gender, race, body weight, renal impairment).
Treatment Of DVT And PE And Reduction In The Risk Of Recurrence Of DVT And PE
Efficacy and safety of ELIQUIS for the treatment of DVT and PE, and for the reduction in the risk of recurrent DVT and PE following 6 to 12 months of anticoagulant treatment was derived from the AMPLIFY and AMPLIFY-EXT studies. Both studies were randomized, parallel-group, double-blind trials in patients with symptomatic proximal DVT and/or symptomatic PE. All key safety and efficacy endpoints were adjudicated in a blinded manner by an independent committee.
AMPLIFY
The primary objective of AMPLIFY was to determine whether ELIQUIS was noninferior to enoxaparin/warfarin for the incidence of recurrent VTE (venous thromboembolism) or VTErelated death. Patients with an objectively confirmed symptomatic DVT and/or PE were randomized to treatment with ELIQUIS 10 mg twice daily orally for 7 days followed by ELIQUIS 5 mg twice daily orally for 6 months, or enoxaparin 1 mg/kg twice daily subcutaneously for at least 5 days (until INR≥2) followed by warfarin (target INR range 2.0-3.0) orally for 6 months. Patients who required thrombectomy, insertion of a caval filter, or use of a fibrinolytic agent, and patients with creatinine clearance <25 mL/min, significant liver disease, an existing heart valve or atrial fibrillation, or active bleeding were excluded from the AMPLIFY study. Patients were allowed to enter the study with or without prior parenteral anticoagulation (up to 48 hours).
A total of 5244 patients were evaluable for efficacy and were followed for a mean of 154 days in the ELIQUIS group and 152 days in the enoxaparin/warfarin group. The mean age was 57 years. The AMPLIFY study population was 59% male, 83% Caucasian, 8% Asian, and 4% Black. For patients randomized to warfarin, the mean percentage of time in therapeutic range (INR 2.0-3.0) was 60.9%.
Approximately 90% of patients enrolled in AMPLIFY had an unprovoked DVT or PE at baseline. The remaining 10% of patients with a provoked DVT or PE were required to have an additional ongoing risk factor in order to be randomized, which included previous episode of DVT or PE, immobilization, history of cancer, active cancer, and known prothrombotic genotype.
ELIQUIS was shown to be noninferior to enoxaparin/warfarin in the AMPLIFY study for the primary endpoint of recurrent symptomatic VTE (nonfatal DVT or nonfatal PE) or VTE-related death over 6 months of therapy (Table 17).
Table 17: Efficacy Results in the AMPLIFY Study
|
ELIQUIS
N=2609
n |
Enoxaparin/ Warfarin
N=2635
n |
Relative Risk
(95% CI) |
| VTE or VTE-related death* |
59 (2.3%) |
71 (2.7%) |
0.84 (0.60, 1.18) |
| DVT† |
22 (0.8%) |
35 (1.3%) |
|
| PE† |
27 (1.0%) |
25 (0.9%) |
|
| VTE-related death† |
12 (0.4%) |
16 (0.6%) |
|
| VTE or all-cause death |
84 (3.2%) |
104 (4.0%) |
0.82 (0.61, 1.08) |
| VTE or CV-related death |
61 (2.3%) |
77 (2.9%) |
0.80 (0.57, 1.11) |
* Noninferior compared to enoxaparin/warfarin (P-value <0.0001).
† Events associated with each endpoint were counted once per subject, but subjects may have contributed events to multiple end points. |
In the AMPLIFY study, patients were stratified according to their index event of PE (with or without DVT) or DVT (without PE). Efficacy in the initial treatment of VTE was consistent between the two subgroups.
AMPLIFY-EXT
Patients who had been treated for DVT and/or PE for 6 to 12 months with anticoagulant therapy without having a recurrent event were randomized to treatment with ELIQUIS 2.5 mg orally twice daily, ELIQUIS 5 mg orally twice daily, or placebo for 12 months. Approximately one-third of patients participated in the AMPLIFY study prior to enrollment in the AMPLIFY-EXT study.
A total of 2482 patients were randomized to study treatment and were followed for a mean of approximately 330 days in the ELIQUIS group and 312 days in the placebo group. The mean age in the AMPLIFY-EXT study was 57 years. The study population was 57% male, 85% Caucasian, 5% Asian, and 3% Black.
The AMPLIFY-EXT study enrolled patients with either an unprovoked DVT or PE at baseline (approximately 92%) or patients with a provoked baseline event and one additional risk factor for recurrence (approximately 8%). However, patients who had experienced multiple episodes of unprovoked DVT or PE were excluded from the AMPLIFY-EXT study. In the AMPLIFY-EXT study, both doses of ELIQUIS were superior to placebo in the primary endpoint of symptomatic, recurrent VTE (nonfatal DVT or nonfatal PE), or all-cause death (Table 18).
Table 18: Efficacy Results in the AMPLIFY-EXT Study
|
ELIQUIS
2.5 mg bid
N=840 |
ELIQUIS
5 mg bid
N=813 |
Placebo
N=829 |
Relative Risk (95% CI) |
ELIQUIS
2.5 mg bid
vs Placebo |
ELIQUIS
5 mg bid
vs Placebo |
|
n (%) |
|
|
| Recurrent VTE or all-cause death |
32 (3.8) |
34 (4.2) |
96 (11.6) |
0.33
(0.22, 0.48)
p<0.0001 |
0.36
(0.25, 0.53)
p<0.0001 |
| DVT* |
19 (2.3) |
28 (3.4) |
72 (8.7) |
|
|
| PE* |
23 (2.7) |
25 (3.1) |
37 (4.5) |
|
|
| All-cause death |
22 (2.6) |
25 (3.1) |
33 (4.0) |
|
|
| * Patients with more than one event are counted in multiple rows. |
Treatment Of VTE And Prevention Of Recurrent VTE In Pediatric Patients From Birth And Older
Study CV185325
ELIQUIS for the treatment of venous thromboembolism (VTE) and reduction in the risk of recurrent VTE was evaluated in Study CV185325, a multicenter, randomized, active-controlled, open-label, multi-center study in 229 pediatric patients from birth to less than 18 years with confirmed VTE. This was a descriptive study and no formal inferences were performed. There were 137 patients aged 12 to < 18 years, 44 patients aged 2 to < 12 years, 32 patients aged 28 days to less than 2 years and 16 patients from birth to less than 27 days. Overall, the median age was 14.2 years with a range of 0.04 to 18.0 years. Neonates and infants were excluded from enrollment if they were < 34 weeks’ gestation (until age of > 6 months) or had a body weight of < 2.6 kg. For pre-term infants born between 34 and <37 weeks gestation, neonates who reached 37 weeks starting from actual date of birth (postnatal age), from 27 day neonatal period starting from actual date of birth (postnatal age), or from when the postmenstrual age (gestational age defined as time elapsed between first day of last normal menstrual period and the day of delivery plus postnatal age) and enrolled the neonate no more than 27 days thereafter. There were 101 (44.1%) males, and 128 (55.9%) females in the study. One hundred and seventy-five (76.4%) patients were White, 31 (13.5%) were Black, 9 (3.9%) were Asian, 4 (1.7%) were Other, 2 (0.9%) were Multiracial and 1 (0.4%) was American Indian or Alaska Native, and 7 (3.1%) were missing this information. Twenty-five (10.9%) were Hispanic or Latino and 204 (89.1%) were not Hispanic or Latino.
Index VTE was classified as deep venous thrombosis (DVT), pulmonary embolism (PE), devicerelated thrombosis (neonatal population only), and other VTE (i.e. cerebral vein and sinus thrombosis, renal vein thrombosis, intracardiac thrombus). Prior to randomization, patients could be treated with SOC anticoagulation for up to 14 days; overall mean (SD) duration of treatment with SOC anticoagulation prior to randomization was 4.9 days, and for 92.9% of patients the duration was between 0 and 7 days. Patients were randomized according to a 2:1 ratio to receive either an age-appropriate formulation and body weight-adjusted doses of ELIQUIS or SOC. For patients 2 to less than 18 years, SOC was comprised of low molecular weight heparins (LMWH), unfractionated heparins (UFH) or vitamin K antagonists (VKA). For patients 28 days to less than 2 years of age, SOC was limited to heparins (UFH or LMWH). The main treatment phase lasted 6 to 12 weeks for patients aged birth to less than 2 years, and 12 weeks for patients aged greater than 2 years. Patients aged 28 days to less than 18 years who were randomized to receive apixaban had the option to continue apixaban treatment for 6 to 12 additional weeks in the extension phase.
A diagnostic imaging test was obtained at baseline, at week 6, and end of treatment for patients ≥2 years of age and at baseline and end of treatment for <2 years of age.
Table 19: Primary efficacy results from Study CV185325
|
ELIQUIS
N=155 |
Standard of care **
N=74 |
| Symptomatic and asymptomatic recurrent VTE* and VTE* related mortality*** |
|
|
| Number (%) Subjects with Event |
4 (2.6) |
2 (2.7) |
| 95% Confidence Interval (1) |
(0.7, 6.5) |
(0.3, 9.4) |
* Recurrent VTE, defined as either contiguous progression or non-contiguous new thrombus and including, but not limited to DVT, PE and paradoxical embolism.
(1) 95% Confidence Interval calculated using the Clopper-Pearson exact method
** UFH/LMWH for patients less than 2 years of age and UFH/LMWH/VKA for those equal to or greater than 2 years of age.
*** no VTE related mortality was observed in either treatment arms during the study. |