Retavase
(reteplase)Retavase Prescribing Information
RETAVASE is indicated for use in acute ST-elevation myocardial infarction (STEMI) to reduce the risk of death and heart failure.
Limitation of Use: The risk of stroke may outweigh the benefit produced by thrombolytic therapy in patients whose STEMI puts them at low risk for death or heart failure.
2.3 Heparin Incompatibility
Heparin and RETAVASE are incompatible. Do not administer RETAVASE through an intravenous line containing heparin.
For Injection: 10 units as a lyophilized powder in single-use vials for reconstitution co-packaged with Sterile Water for Injection, USP in 10 mL prefilled syringe.
8.1 Pregnancy
Risk Summary
Limited published data with RETAVASE use in pregnant women are insufficient to inform a drug associated risk of adverse developmental outcomes. In animal reproduction studies, reteplase administered to pregnant rabbits resulted in hemorrhaging in the genital tract, leading to abortions in mid-gestation in doses 3 times the human dose; however, there was no evidence of fetal anomalies in rats at doses up to 15 times the human dose.
The estimated background risk of major birth defects and miscarriage for the indicated population(s) are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.
Clinical Considerations
Maternal Adverse Reactions
The most common complication of thrombolytic therapy is bleeding and pregnancy may increase this risk.
Data
Animal Data
Reteplase was administered to pregnant rabbits in doses 3 times the human dose (0.86 units/kg) resulting in hemorrhaging in the genital tract, leading to abortions in mid-gestation. In animal developmental studies in rats at Reteplase doses up to 15 times the human dose (4.31 units/kg), there was no evidence of fetal anomalies.
8.2 Lactation
Risk Summary
There are no data on the presence of reteplase in either human or animal milk, the effects on the breastfed infant, or the effects on milk production. RETEVASE has not been studied in nursing mothers.
8.4 Pediatric Use
Safety and effectiveness of RETAVASE in pediatric patients have not been established.
Because thrombolytic therapy increases the risk of bleeding, RETAVASE is contraindicated in the following situations:
- Active internal bleeding
- Recent stroke
- Intracranial or intraspinal surgery or serious head trauma within 3 months
- Intracranial conditions that increase the risk of bleeding (e.g. neoplasms, arteriovenous malformation, or aneurysms)
- Bleeding diathesis
- Current severe uncontrolled hypertension
5.4 Drug/Laboratory Test Interactions
Coagulation tests and measures of fibrinolytic activity are unreliable during RETAVASE therapy unless specific precautions are taken to prevent in vitro artifacts. When present in blood at pharmacologic concentrations, RETAVASE remains active under in vitro conditions, which can result in degradation of fibrinogen in blood samples removed for analysis.
6.1 Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction 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.
Bleeding
The most frequent adverse reaction associated with RETAVASE is bleeding.
- Intracranial hemorrhage [see Clinical Studies ]
In the INJECT clinical trial, the overall rate of in-hospital, intracranial hemorrhage was 0.8%. The risk for intracranial hemorrhage is increased in patients with advanced age (2.2% among patients >70 years old) or with elevated blood pressure (2.4% among patients with systolic blood pressure >160 mmHg).
- Other types of hemorrhage
The incidence of other types of bleeding events in clinical studies of RETAVASE varied depending upon the use of arterial catheterization or other invasive procedures and whether the study was performed in Europe or the USA. The overall incidence of any bleeding event in patients treated with RETAVASE in clinical studies (n = 3,805) was 21.1%. The rates for bleeding events, regardless of severity, for the 10 + 10 unit RETAVASE regimen from controlled clinical studies are summarized in Table 1.
Table 1: RETAVASE Hemorrhage Rates
| Bleeding Site | INJECT | RAPID 1 and RAPID 2 | |
|---|---|---|---|
| Europe N = 2,965 | USA N = 210 | Europe N =113 | |
| |||
Injection Site * | 4.6% | 48.6% | 19.5% |
Gastrointestinal | 2.5% | 9.0% | 1.8% |
Genitourinary | 1.6% | 9.5% | 0.9% |
Anemia, site unknown | 2.6% | 1.4% | 0.9% |
In these studies the severity and sites of bleeding events were similar for RETAVASE and the comparison thrombolytic agents.
Allergic Reactions
Among the 2,965 patients receiving RETAVASE in the INJECT trial, serious allergic reactions were noted in 3 patients, with one patient experiencing dyspnea and hypotension.
Among the 9,938 patients that received RETAVASE in a postmarketing clinical study, 8 patients experienced allergic and/or anaphylactoid reactions. Signs and symptoms observed included rash, pruritis, erythema, glossal (tongue) edema, hypotension, and respiratory distress.
Reteplase is a non-glycosylated deletion mutein of tissue plasminogen activator (tPA), containing the kringle 2 and the protease domains of human tPA. Reteplase contains 355 of the 527 amino acids of native tPA (amino acids 1-3 and 176-527). Reteplase is produced by recombinant DNA technology in E. coli. The protein is isolated as inactive inclusion bodies from E. coli, converted into its active form by an in vitro folding process and purified by chromatographic separation. The molecular weight of Reteplase is 39,571 daltons.
Potency is expressed in units (U) using a reference standard which is specific for RETAVASE and is not comparable with units used for other thrombolytic agents.
RETAVASE (reteplase) for Injection is a sterile, white, lyophilized powder for intravenous injection after reconstitution with Sterile Water for Injection, USP (without preservatives). Following reconstitution with 10 mL of Sterile Water for Injection, the resulting concentration is 1 unit/mL to allow for delivery of 10 mL (10 units reteplase). The pH is 6.0 ± 0.3. RETAVASE is supplied with overfill to ensure sufficient drug for administration of each 10 unit injection.
Each single-use vial delivers:
Reteplase | 10 units |
Dipotassium Hydrogen Phosphate | 131 mg |
Phosphoric Acid | 49.3 mg |
Polysorbate 80 | 5 mg |
Sucrose | 350 mg |
Tranexamic Acid | 8 mg |
12.1 Mechanism of Action
RETAVASE is a recombinant plasminogen activator which catalyzes the cleavage of endogenous plasminogen to generate plasmin. Plasmin in turn degrades the fibrin matrix of the thrombus, thereby exerting its thrombolytic action.
12.2 Pharmacodynamics
In a controlled trial, 36 of 56 patients treated for myocardial infarction had a decrease in fibrinogen levels to below 100 mg/dL by 2 hours following the administration of RETAVASE as two intravenous injections (10 + 10 unit) in which 10 units was followed 30 minutes later by a second dose of 10 units. The mean fibrinogen level returned to the baseline value by 48 hours.
12.3 Pharmacokinetics
Based on the measurement of thrombolytic activity, RETAVASE is cleared from plasma at a rate of 250-450 mL/min, with an effective half-life of 13-16 minutes. RETAVASE is cleared primarily by the liver and kidney.
13.1 Carcinogenesis and Mutagenesis
Long-term studies in animals have not been performed to evaluate the carcinogenic potential of RETAVASE. Studies to determine mutagenicity, chromosomal aberrations, gene mutations, and micronuclei induction were negative at all concentrations tested.
RETAVASE was evaluated in three controlled clinical studies comparing RETAVASE to other thrombolytic agents. In all three studies, patients were treated with aspirin (initial doses of 160 mg to 350 mg and subsequent doses of 75 mg to 350 mg) and heparin (a 5,000 unit IV bolus prior to the administration of RETAVASE or control, followed by a 1000 unit/hour continuous IV infusion for at least 24 hours).
The INJECT study compared RETAVASE to streptokinase on mortality rates at 35 days following acute ST-elevation myocardial infarction (STEMI). INJECT was a double-blind study in which 6,010 patients with no more than 12 hours of chest pain consistent with coronary ischemia and either ST segment elevation or bundle branch block on ECG were randomized 1:1 to RETAVASE (10 + 10 unit) or streptokinase (1.5 million units over 60 minutes). Patients with cerebrovascular or other bleeding risks or with systolic blood pressure >200 mm Hg or diastolic blood pressure >100 mm Hg were excluded from enrollment. The study was designed to determine whether the effect of RETAVASE on survival was noninferior to that of streptokinase by ruling out with 95% confidence that 35-day mortality among RETAVASE patients was no more than 1% higher than among streptokinase patients. The results of the primary endpoint (mortality at 35 days), 6-month mortality, and selected other in-hospital endpoints are shown in Table 2.
Table 2: INJECT Study: Selected Results
| Endpoint | RETAVASE N=2,965 | Streptokinase N = 2,971 | RETAVASE-Streptokinase ∆(95% CI) |
|---|---|---|---|
| |||
35-day mortality * | 8.9% | 9.4% | -0.5 (-2.0, 0.9) |
6-month mortality | 11.0% | 12.1% | -1.1 (-2.7, 0.6) |
Cardiogenic shock | 4.6% | 5.8% | -1.2 (-2.4, -0.1) |
Heart failure in-hospital | 24.8% | 28.1% | -3.3 (-5.6, -1.1) |
Any stroke in-hospital | 1.4% | 1.1% | 0.3 (-0.3, 0.8) |
Intracranial hemorrhage in-hospital | 0.8% | 0.4% | 0.4 (0.0, 0.8) |
More patients treated with RETAVASE experienced hemorrhagic strokes than did patients treated with streptokinase. An exploratory analysis indicated that the incidence of intracranial hemorrhage was higher among older patients or those with elevated blood pressure.
The other two studies (RAPID 1 and RAPID 2) compared coronary artery patency of RETAVASE to two regimens of alteplase in patients with STEMI. In RAPID 1 patients within 6 hours of the onset of symptoms were randomized to open-label administration of one of three regimens of RETAVASE (doses of 10 + 10 unit, 15 unit, or 10 + 5 unit) or to alteplase (100 mg over 3 hours). In RAPID 2 patients within 12 hours of the onset of symptoms were randomized to open-label administration of either RETAVASE (10 + 10 unit) or alteplase (100 mg over 1.5 hours). The primary endpoint for both studies was patency of the infarct-related artery 90 minutes after initiation of therapy. Interpretation of coronary angiograms was blinded.
A higher percentage of subjects administered RETEVASE had complete flow (TIMI grade 3) and partial or complete flow (TIMI grades 2 or 3) compared to both regimens of alteplase. The relationship between coronary artery patency and clinical efficacy has not been established.
In both clinical trials the re-occlusion rates were similar for RETAVASE and alteplase.
Table 3: RAPID 1 and RAPID 2 Studies: Angiographic Results
| 90 minute patency rates | RAPID 2 | RAPID 1 * | ||||
|---|---|---|---|---|---|---|
| RETAVASE(10 +10 unit)N = 157 | Alteplase(100 mg over 1.5 hours)N = 146 | p- value | RETAVASE(10 +10 unit)N = 142 | Alteplase(100 mg over 3 hours)N = 145 | p- value | |
| ||||||
TIMI 2 or 3 | 83% | 73% | 0.03 | 85% | 77% | 0.08 |
TIMI 3 | 60% | 45% | 0.01 | 63% | 49% | 0.02 |
RETAVASE (reteplase) for Injection is supplied as a sterile, preservative-free, lyophilized powder in 10 unit vials without a vacuum, in the following packaging configurations:
RETAVASE Kit (NDC 10122-141-02): 2 single-use RETAVASE vials 10 units, 2 single-use prefilled syringes for reconstitution (10 mL Sterile Water for Injection, USP), 2 syringe plungers, 2 sterile 10 mL graduated syringes, 2 sterile reconstitution spikes, 1 quick reference guide and 1 package insert.
RETAVASE Half-Kit (NDC 10122-143-01): 1 single-use RETAVASE vial 10 units, 1 single-use prefilled syringe for reconstitution (10 mL Sterile Water for Injection, USP), 1 syringe plunger, 1 sterile 10 mL graduated syringe, 1 sterile reconstitution spike, 1 quick reference guide and 1 package insert.
Storage: Store RETAVASE at 2°C to 25°C (36°F to 77°F). The box should remain sealed until use to protect the lyophilisate from exposure to light.
Manufactured by:
Chiesi USA, Inc.
Cary, NC 27518
U.S. License No. 2150
Retavase® manufactured at Patheon Italia, S.p.A., Monza, Italy 20900.
To report an adverse event, record the lot number and call Medical Information at 1-888-661-9260.
RETAVASE® is a registered trademark of Chiesi USA, Inc.
The trademarks Streptase®, Activase®, and Actilyse® referenced herein are the property of their respective owners and are not affiliated with, connected to, or sponsored by Chiesi USA, Inc.
CTR-001-0422-03-SPL-1
12.1 Mechanism of Action
RETAVASE is a recombinant plasminogen activator which catalyzes the cleavage of endogenous plasminogen to generate plasmin. Plasmin in turn degrades the fibrin matrix of the thrombus, thereby exerting its thrombolytic action.