Consumer medicine information

AGGRASTAT

Tirofiban

BRAND INFORMATION

Brand name

Aggrastat Concentrate for infusion

Active ingredient

Tirofiban

Schedule

S4

 

Consumer medicine information (CMI) leaflet

Please read this leaflet carefully before you start using AGGRASTAT.

What is in this leaflet

This leaflet answers some common questions about AGGRASTAT. It does not contain all the available information.

It does not take the place of talking to your doctor or pharmacist.

All medicines have risks and benefits. Your doctor has weighed the risks of you using AGGRASTAT against the benefits they expect it will have for you.

If you have any concerns about being given this medicine, ask your doctor or pharmacist.

Keep this leaflet.

You may need to read it again.

What AGGRASTAT is used for

AGGRASTAT, in combination with heparin (another medicine used to prevent blood clots), is used to prevent complications that may occur in people who have unstable angina (a type of chest pain) or are having a heart attack.

AGGRASTAT belongs to a group of medicines called platelet aggregation inhibitors.

It works by preventing cells in the blood, called platelets, from sticking together to form blood clots. If blood clots are not treated or prevented, they can block blood vessels. This can lead to complications such as angina or heart attacks.

Before you are given AGGRASTAT

When you must not be given it

Do not use AGGRASTAT if you have an allergy to AGGRASTAT or any of the ingredients listed at the end of this leaflet

Do not use AGGRASTAT if you have any of the following medical conditions:

  • bleeding inside your body, or a history of increased tendency to bleeding, especially within the last 30 days
  • a history of bleeding in the brain or brain tumour
  • a history of abnormal or deformed arteries or veins
  • a history of swelling and weakening of a part of a blood vessel, also called aneursym
  • a history of stroke, especially within the last 30 days, or any history of stroke due to bleeding in the brain
  • major surgery or physical trauma, including falls or blows to the body or head, especially within the last month
  • a history, symptoms or signs of aortic dissection, a disease of a large blood vessel
  • severe, uncontrolled high blood pressure
  • pericarditis, a condition which involves swelling of the lining that surrounds the heart.

If you are not sure whether you should start receiving AGGRASTAT, talk to your doctor.

Do not use AGGRASTAT if you have received AGGRASTAT before and developed a low platelet count.

If you are not sure whether you have received AGGRASTAT before and developed a low platelet count, ask your doctor.

Do not use AGGRASTAT if you are already receiving an injection of another 'platelet aggregation inhibitor' medicine.

Do not use AGGRASTAT if you are breast-feeding or intend to breast-feed.

AGGRASTAT is not recommended for use while breast-feeding. It is not known whether it passes into breast milk.

Do not use AGGRASTAT in children.

The safety and effectiveness in children have not been established.

Before you are given it

Tell your doctor if:

  1. you are pregnant
    Like most medicines, AGGRASTAT is generally not recommended during pregnancy. However, if there is a need to consider using AGGRASTAT during pregnancy, your doctor will discuss the possible risks and benefits to you and your unborn baby.
  2. you have or have had any medical conditions, especially the following:
  • any bleeding problems, including stomach bleeding, or blood in your urine or stools, within the last year
  • blood clotting problems or platelet diseases, including low platelet count
  • disease of the blood vessels of the brain, including stroke, within the last year
  • problems with the blood vessels in the back of your eye/s
  • kidney disease, or are undergoing dialysis
  1. you have received platelet aggregation inhibitors before
  2. you recently had an epidural (spinal) procedure
  3. you have any allergies to any other medicines or any other substances, such as foods, preservatives or dyes.

If you have not told your doctor about any of the above, tell them before you are given AGGRASTAT.

Taking other medicines

Tell your doctor if you are taking any other medicines, including medicines that you buy without a prescription from your pharmacy, supermarket or health food shop. Some medicines and AGGRASTAT may interfere with each other. This includes:

  • medicines used to dissolve or prevent blood clots, including warfarin

These medicines may be affected by AGGRASTAT, or may affect how well it works. You may need different amounts of your medicine, or you may need to take different medicines.

Your doctor or pharmacist has more information on medicines to be careful with or to avoid while being given AGGRASTAT.

How AGGRASTAT is given

AGGRASTAT is given as a slow injection into a vein.

AGGRASTAT must only be given by a doctor or nurse.

Your doctor will decide what dose and how long you will receive AGGRASTAT. This depends on your condition and other factors, such as your weight and kidney function.

Side Effects

Tell your doctor, nurse, or pharmacist as soon as possible if you do not feel well while you are being given AGGRASTAT.

AGGRASTAT helps most people, but it may have unwanted side-effects in a few people. All medicines can have side effects. Sometimes they are serious, most of the time they are not. You may need medical treatment if you get some of the side effects.

Ask your doctor or pharmacist to answer any questions you may have.

Tell your doctor or nurse immediately if you notice any unusual bleeding or bruising.

This includes bleeding gums, nose bleeds, blood in your urine, bloody or black, tarry stools, coughing up blood, vomiting blood or material that looks like coffee grounds.

These may be serious side effects of AGGRASTAT. You may need urgent medical attention.

Also, tell your doctor or nurse immediately if you notice any of the following:

  • rash
  • pinkish, itchy swellings on the skin, also called hives or nettlerash
  • swelling of the face, lips, mouth or throat which may cause difficulty in swallowing or breathing
  • chills, dizziness, or wheezing

If you have them, you may be having an allergic reaction to AGGRASTAT. You may need urgent medical attention.

Tell your doctor or nurse if you notice any of the following and they worry you:

  • fever
  • nausea
  • headache

These are usually mild side effects of AGGRASTAT.

Other side effects not listed above may also occur in some patients. Tell your doctor if you notice any other effects.

Do not be alarmed by this list of possible side effects. You may not experience any of them.

Storage

AGGRASTAT will be stored in the pharmacy or on the ward.

It is kept in a cool, dry place where it is protected from light and where the temperature stays below 30 degrees C.

Product Description

What it looks like

AGGRASTAT comes in a glass vial, containing 50 mL of solution.

Ingredients

Active ingredient:

  • 0.25 of tirofiban per mL

Inactive ingredients:

  • citric acid anhydrous
  • sodium citrate dihydrate
  • sodium chloride
  • water for injections

Supplier

AGGRASTAT is supplied in Australia by:
Aspen Pharmacare Australia Pty Ltd
34-36 Chandos St
St Leonards NSW 2065
Australia

This leaflet was prepared in February 2001.
Updated May 2013

Australian Register Number:
AUST R 65162

®Registered Trademark of Correvio U.S.A

BRAND INFORMATION

Brand name

Aggrastat Concentrate for infusion

Active ingredient

Tirofiban

Schedule

S4

 

Notes

Distributed by Aspen Pharmacare Australia Pty Ltd

1 Name of Medicine

Tirofiban hydrochloride.

2 Qualitative and Quantitative Composition

Each mL of the solution contains 0.281 mg of the active tirofiban hydrochloride monohydrate equivalent to 0.25 mg of tirofiban. The pH ranges from 5.5 to 6.5 and may have been adjusted with hydrochloric acid and/or sodium hydroxide.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Aggrastat Concentrate for Infusion is a clear sterile concentrated solution for intravenous infusion after dilution and is supplied in a 50 mL glass vial.

4 Clinical Particulars

4.1 Therapeutic Indications

Aggrastat, in combination with heparin, is indicated for patients with unstable angina or non-Q wave myocardial infarction to prevent cardiac ischaemic events.
(See Section 4.2 Dose and Method of Administration; Section 5 Pharmacological Properties).

4.2 Dose and Method of Administration

The vial of Aggrastat (concentrate) must be diluted prior to administration (see Instructions for use).
Aggrastat is for intravenous use only using sterile equipment. Aggrastat may be coadministered with heparin through the same line. Aggrastat should not be administered in the same intravenous line as diazepam.
Aggrastat is recommended for use with a calibrated infusion device. Care should be taken to avoid a prolonged loading infusion. Care should also be taken in calculating the bolus dose and infusion rates based on patient weight.
In clinical studies patients received aspirin, unless contraindicated.
Aggrastat should be administered intravenously at the initial infusion rate of 0.4 microgram/kg/minute for 30 minutes. Upon completion of the initial infusion, Aggrastat should be continued at a maintenance infusion rate of 0.1 microgram/kg/minute. Aggrastat should be given with heparin (usually an intravenous bolus dose of 5,000 U simultaneously with the start of therapy with Aggrastat, then approximately 1,000 U per hour titrated on the basis of APTT, which should be about twice the normal value).
In the study that demonstrated efficacy, Aggrastat in combination with heparin was generally continued for a minimum of 48 hours and up to 108 hours. This infusion can be continued through angiography and should be continued up to 12 to 24 hours post-angioplasty/atherectomy. Arterial sheaths should be removed when the patient's activated clotting time is < 180 seconds or two to six hours following cessation of heparin. (See Section 5.1 Pharmacodynamic Properties, Clinical trials).

Patients with severe renal insufficiency.

The dosage of Aggrastat should be decreased by 50% in patients with severe renal insufficiency (creatinine clearance < 30 mL/minute). (See Section 4.4 Special Warnings and Precautions for Use, Severe renal insufficiency).
Table 1 is provided as a guide to dosage adjustment by weight.

Other patient populations.

No dosage adjustment is recommended for elderly patients (see Section 4.4 Special Warnings and Precautions for Use, Use in the elderly) or female patients.

Instructions for use.

Parenteral drug products should be inspected visually for particulate matter and discolouration prior to use, whenever solution and container permit.

Concentrate for infusion.

The vial of Aggrastat (concentrate) must be diluted prior to administration. It contains no antimicrobial agent. Use once only and discard any residue.

Directions for preparation of Aggrastat solution for infusion from concentrate.

1. Withdraw and discard 50 mL from a 250 mL bag of sterile 0.9% saline or 5% glucose in water and replace it with 50 mL of Aggrastat (from one 50 mL vial) to achieve a final concentration of 0.05 mg/mL. Mix well before administration.
Alternatively, withdraw and discard 100 mL from a 500 mL bag of sterile 0.9% saline or 5% glucose in water and replace it with 100 mL of Aggrastat (from two 50 mL vials) to achieve a final concentration of 0.05 mg/mL. Mix well before administration.
2. Administer according to the appropriate dosage calculations above.
3. To reduce microbiological hazard, use as soon as practicable after dilution. Discard any unused intravenous solution after 24 hours following start of infusion. If storage is necessary, hold at 2-8°C for not more than 24 hours.

4.3 Contraindications

Aggrastat is contraindicated in patients with:
Known hypersensitivity to any component of the product.
Active internal bleeding or a history of bleeding diathesis within the previous 30 days.
A history of intracranial haemorrhage, intracranial neoplasm, arteriovenous malformation, or aneurysm.
A history of thrombocytopenia following prior exposure to Aggrastat.
History of stroke within 30 days or any history of haemorrhagic stroke.
Major surgical procedure (including epidural or spinal anaesthesia) or severe physical trauma within 1 month.
History, symptoms, or findings suggestive of aortic dissection.
Severe uncontrolled hypertension (systolic blood pressure > 180 mmHg and/or diastolic blood pressure > 110 mmHg).
Concomitant use of another parenteral GP IIb/IIIa inhibitor.
Acute pericarditis.

4.4 Special Warnings and Precautions for Use

Aggrastat should be used with caution in the following patients:
Recent (< 1 year) bleeding, including a history of gastrointestinal bleeding or genitourinary bleeding of clinical significance.
Known coagulopathy, platelet disorder or history of thrombocytopenia.
Platelet count < 150,000 cells/mm3.
History of cerebrovascular disease within one year.
Recent epidural procedure.
Haemorrhagic retinopathy.
Chronic haemodialysis.

Bleeding precautions.

Because Aggrastat inhibits platelet aggregation, caution should be employed when it is used with other drugs that affect haemostasis. The safety of Aggrastat when used in combination with thrombolytic agents has not been established.
During therapy with Aggrastat, patients should be monitored for potential bleeding. When treatment of bleeding is required, discontinuation of the drug should be considered. Consideration may also be given to transfusions.
Fatal bleedings have been reported (see Section 4.8 Adverse Effects (Undesirable Effects)).

Femoral artery access site.

Aggrastat is associated with minor increases in bleeding rates particularly at the site of arterial access for femoral sheath placement. Care should be taken when attempting vascular access that only the anterior wall of the femoral artery is punctured, avoiding a Seldinger (through and through) technique for obtaining sheath access. Care should be taken to obtain proper haemostasis after removal of the sheaths followed by close observation.

Laboratory monitoring.

Platelet counts, and haemoglobin and haematocrit should be monitored prior to treatment, within 6 hours following the bolus or loading infusion, and at least daily thereafter during therapy with Aggrastat (or more frequently if there is evidence of significant decline). In patients who have previously received GP IIb/IIIa receptor antagonists, consideration should be given to earlier monitoring of platelet count. If the patient experiences a platelet count decrease to < 90,000 cells/mm3, additional platelet counts should be performed to exclude pseudothrombocytopenia. If thrombocytopenia is confirmed, Aggrastat and heparin should be discontinued and the condition appropriately monitored and treated.
In addition, the activated partial thromboplastin time (APTT) should be determined before treatment and the anticoagulant effects of heparin should be carefully monitored by repeated determinations of APTT and the dose adjusted accordingly (see Section 4.2 Dose and Method of Administration). Potentially life threatening bleeding may occur especially when heparin is administered with other products affecting haemostasis, such as GP IIb/IIIa receptor antagonists.

Severe renal insufficiency.

In clinical studies, patients with severe renal insufficiency (creatinine clearance < 30 mL/minute) demonstrated decreased plasma clearance of Aggrastat. The dosage of Aggrastat should be reduced in these patients (see Section 4.2 Dose and Method of Administration; Section 5.1 Pharmacodynamic Properties, Clinical trials).

Use in the elderly.

In clinical studies the efficacy of Aggrastat in the elderly (≥ 65 years) was comparable to that seen in younger patients (< 65 years). Elderly patients receiving Aggrastat with heparin or heparin alone had a higher incidence of bleeding complications than younger patients. The incremental risk of bleeding in patients treated with Aggrastat in combination with heparin over the risk in patients treated with heparin alone was comparable regardless of age. The overall incidence of nonbleeding adverse events was higher in older patients (compared to younger patients); however, the incidence of non-bleeding adverse events in these patients was comparable between the Aggrastat with heparin and the heparin alone groups. No dose adjustment is recommended (see Section 4.2 Dose and Method of Administration).
This drug is known to be excreted by the kidney. A 50% reduction in dose is recommended for patients with severe renal insufficiency (creatinine clearance < 30 mL/minute) (see Section 4.2 Dose and Method of Administration; Section 4.4 Special Warnings and Precautions for Use). Plasma clearance of Aggrastat is about 19 to 26% lower in elderly (> 65 years) patients with coronary artery disease compared to younger (≤ 65 years) patients.

Paediatric use.

Safety and effectiveness in children have not been established.

Effects on laboratory tests.

The most frequently observed laboratory adverse events in patients receiving Aggrastat concomitantly with heparin were related to bleeding. Decreases in haemoglobin and haematocrit, and platelet count were observed. Increases in the presence of urine and faecal occult blood were also observed.

4.5 Interactions with Other Medicines and Other Forms of Interactions

Aggrastat has been studied on a background of aspirin and heparin.
The use of Aggrastat, in combination with heparin and aspirin, has been associated with an increase in bleeding compared to heparin and aspirin alone (see Section 4.8 Adverse Effects (Undesirable Effects)). Caution should be employed when Aggrastat is used with other drugs that affect haemostasis (e.g. warfarin) (see Section 4.4 Special Warnings and Precautions for Use, Bleeding precautions). The safety of Aggrastat when used in combination with thrombolytic agents has not been established.
Aggrastat has been used concomitantly in clinical studies with beta-blockers, calcium channel blockers, nonsteroidal anti-inflammatory drugs (NSAIDs) and nitrate preparations without evidence of clinically significant adverse interactions.
In a subset of patients (n = 762) in the PRISM study, the plasma clearance of tirofiban in patients receiving one of the following drugs was compared to that in patients not receiving that drug. There were no clinically significant interactions of these drugs on the plasma clearance of tirofiban: acebutolol, alprazolam, amlodipine, aspirin preparations, atenolol, bromazepam, captopril, diazepam, digoxin, diltiazem, docusate sodium, enalapril, frusemide, glibenclamide, heparin, insulin, isosorbide, thyroxine sodium, lorazepam, lovastatin, metoclopramide, metoprolol, morphine, nifedipine, nitrate preparations, omeprazole, oxazepam, paracetamol, potassium chloride, propranolol, ranitidine, simvastatin, sucralfate and temazepam.

4.6 Fertility, Pregnancy and Lactation

Effects on fertility.

Fertility and reproductive performance were not affected in studies with male and female rats given intravenous doses of tirofiban hydrochloride up to 5 mg/kg/day.
(Category B1)
There are no adequate and well controlled studies in pregnant women. Aggrastat should be used during pregnancy only if the potential benefit justifies the potential risk to the foetus.
Studies of developmental toxicity in rats and rabbits showed no evidence of maternal or foetal toxicity. In addition, a study of the potential developmental toxicity through sexual maturity of rats exposed in utero and during lactation showed no drug related effects on mortality, growth, development, and sexual maturation of the F1 generation. In the developmental toxicity studies, dams were given tirofiban hydrochloride intravenously at doses up to 5 mg/kg/day.
It is not known whether Aggrastat is excreted in human milk, but it is excreted in rat milk. Because many drugs are excreted in human milk, and because of the potential for adverse effects on the nursing infant, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. Tirofiban hydrochloride crosses the placenta in rats and rabbits.

4.7 Effects on Ability to Drive and Use Machines

The effects of this medicine on a person's ability to drive and use machines were not assessed as part of its registration.

4.8 Adverse Effects (Undesirable Effects)

Bleeding.

The most common drug related adverse event reported during therapy with Aggrastat when used concomitantly with heparin and aspirin, was bleeding, usually reported by the investigators as oozing or mild. (See Section 4.4 Special Warnings and Precautions for Use, Effects on laboratory tests.)
The incidences of major and minor bleeding using the TIMI** Criteria in the PRISM PLUS (Platelet Receptor Inhibition for Ischaemic Syndrome Management - Patients Limited by Unstable Signs and Symptoms) study are shown in Table 2.
** Bovill, E.G.; et al: Haemorrhagic Events during Therapy with Recombinant Tissue-Type Plasminogen Activator, Heparin, and Aspirin for Acute Myocardial Infarction, Results of the Thrombolysis in Myocardial Infarction (TIMI), Phase II Trial, Annals of Internal Medicine, 115(4): 256-265, 1991.
There were no reports of intracranial bleeding in the PRISM PLUS study for Aggrastat in combination with heparin or in the control group (which received heparin). In the PRISM PLUS study, the incidences of retroperitoneal bleeding reported for Aggrastat in combination with heparin, and for the control group were 0.0% and 0.1%, respectively.
Female patients and elderly patients receiving Aggrastat with heparin or heparin alone had a higher incidence of bleeding complications than male patients or younger patients, respectively. The incremental risk of bleeding in patients treated with Aggrastat in combination with heparin over the risk in patients treated with heparin alone was comparable regardless of age or gender. No dose adjustment is recommended for these populations (see Section 4.2 Dose and Method of Administration).

Thrombocytopenia.

Patients treated with Aggrastat, with heparin, were more likely to experience decreases in platelet counts than the control group. These decreases were reversible upon discontinuation of Aggrastat. The percentage of patients with a decrease of platelets to < 90,000 cells/mm3 was 1.5%. The percentage of patients with a decrease of platelets to < 50,000 cells/mm3 was 0.3%. Platelet decreases have been observed in patients with no prior history of thrombocytopenia upon readministration of GP IIb/IIIa receptor antagonists.

Other adverse reactions.

The most frequent drug related non-bleeding adverse reactions reported with Aggrastat, administered concomitantly with heparin, occurring at an incidence of > 1% were: nausea (1.7% v 1.4% control), fever (1.5% v 1.1% control), headache (1.1% v 1.2% control).
In clinical studies, the incidences of adverse events were generally similar among different races, patients with or without hypertension, patients with or without diabetes mellitus, and patients with or without hypercholesterolaemia.
The overall incidence of non-bleeding adverse events was higher in female patients (compared to male patients) and older patients (compared to younger patients). However, the incidences of non-bleeding adverse events in these patients were comparable between the Aggrastat with heparin and the heparin alone groups. (See above for bleeding adverse events).
The following additional adverse reactions have been reported in postmarketing experience:

Bleeding.

Intracranial bleeding, retroperitoneal bleeding, haemopericardium, pulmonary (alveolar) haemorrhage and spinal epidural haematoma. Fatal bleedings have been reported rarely.

Body as a whole.

Acute and/or severe decreases in platelet counts which may be associated with chills, low grade fever, or bleeding complications (see above).

Hypersensitivity.

Rash and urticaria. Severe allergic reactions including anaphylactic reactions. The reported cases have occurred during the first day of tirofiban infusion, during initial treatment, and during readministration of tirofiban. Some cases have been associated with severe thrombocytopenia (platelet counts < 10,000/mm3).

Reporting suspected adverse effects.

Reporting suspected adverse reactions after registration of the medicinal product is important. It allows continued monitoring of the benefit-risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions at www.tga.gov.au/reporting-problems.

4.9 Overdose

In clinical trials, inadvertent overdosage with tirofiban occurred in doses up to 5 times and 2 times the recommended dose for bolus administration and loading infusion, respectively. Inadvertent overdosage occurred in doses up to 9.8 times the 0.15 microgram/kg/minute maintenance infusion rate.
The most frequently reported manifestation of overdosage was bleeding, primarily minor mucocutaneous bleeding events and minor bleeding at the sites of cardiac catheterisation (see Section 4.4 Special Warnings and Precautions for Use, Bleeding precautions).
Overdosage of tirofiban should be treated by assessment of the patient's clinical condition and cessation or adjustment of the drug infusion as appropriate.
Aggrastat can be removed by haemodialysis.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).

5 Pharmacological Properties

5.1 Pharmacodynamic Properties

Aggrastat (tirofiban hydrochloride,), a non-peptide antagonist of the platelet glycoprotein (GP) IIb/IIIa receptor, is a platelet aggregation inhibitor.
Aggrastat causes potent inhibition of platelet function as demonstrated by its ability to inhibit ex vivo adenosine phosphate (ADP)-induced platelet aggregation and prolong bleeding time (BT) in healthy subjects and patients with coronary artery disease. The time course of inhibition parallels the plasma concentration profile of the drug. Following discontinuation of an infusion of Aggrastat, platelet function rapidly returns to baseline.
Coadministration of a 4-hour infusion of 0.15 microgram/kg/min of Aggrastat and aspirin results in the anticipated near maximal inhibition of platelet aggregation and a modest additive effect of BT prolongation.
In patients with unstable angina, a two-staged intravenous infusion regimen of Aggrastat (loading infusion of 0.4 microgram/kg/min for 30 minutes followed by 0.1 microgram/kg/min for up to 48 hours in the presence of heparin and aspirin), produces approximately 90% inhibition of ex vivo ADP-induced platelet aggregation with a 2.9-fold prolongation of bleeding time during the infusion. Inhibition was achieved rapidly with the 30-minute loading infusion and was maintained over the duration of the infusion.

Mechanism of action.

Platelet activation, adhesion and aggregation represent critical initiating steps in the formation of arterial thrombus overlying disrupted atherosclerotic plaque. Thrombus formation is central to the pathophysiology of the acute coronary ischaemic syndromes of unstable angina and myocardial infarction, as well as to cardiac ischaemic complications following coronary angioplasty.
Aggrastat is a nonpeptide antagonist of the platelet glycoprotein (GP) IIb/IIIa receptor, the major platelet surface receptor involved in platelet aggregation. Aggrastat prevents binding of fibrinogen to GP IIb/IIIa, thereby blocking the crosslinking of platelets and platelet aggregation.

Clinical trials.

Unstable angina/non-Q wave myocardial infarction.

PRISM-PLUS (platelet receptor inhibition for ischaemic syndrome management - patients limited by unstable signs and symptoms).

In the multicentre, randomised, parallel, double blind PRISM PLUS trial, the use of Aggrastat in combination with heparin versus heparin alone was evaluated in patients with documented unstable angina/non-Q wave myocardial infarction.
In this study, patients were randomised to either Aggrastat (30 minute loading infusion of 0.4 microgram/kg/minute followed by a maintenance infusion of 0.10 microgram/kg/minute) and heparin (bolus of 5,000 units (U) followed by an infusion of 1,000 U/hour titrated to maintain an activated partial thromboplastin time (APTT) of approximately 2 times control), or heparin alone (bolus of 5,000 U followed by an infusion of 1,000 U/hour titrated to maintain an APTT of approximately 2 times control). A third group of patients was initially randomised to Aggrastat (30 minute loading dose of 0.6 microgram/kg/minute followed by a maintenance infusion of 0.15 microgram/kg/minute) with no heparin. This arm was discontinued when an increase in mortality was noted at seven days (16 deaths (4.6%) with tirofiban, as compared with 4 deaths (1.1%) with heparin).
All patients received concomitant aspirin unless contraindicated. Therapy with Aggrastat commenced within 12 hours of the last episode of chest pain. Patients underwent 48 hours of medical stabilisation on study drug therapy, after which angiography and angioplasty/atherectomy remained options while continuing on Aggrastat. Aggrastat was generally administered for a minimum of 48 hours and was continued up to 108 hours; on average, patients received Aggrastat for 71.3 hours.
The primary endpoint of the study was a composite of refractory ischaemia, new myocardial infarction and death at 7 days following initiation of Aggrastat. At the primary endpoint, there was a 31.6% risk reduction in the overall composite, a 46.6% risk reduction in myocardial infarction, and a 42.8% risk reduction in the composite of myocardial infarction and death. The results are shown in Table 3.
At 30 days, the risk of the composite endpoint was reduced by 22% (p = 0.029) and there was a 30% reduction in the composite of death and myocardial infarction (p = 0.027).
At 6 months, the risk of the composite endpoint was reduced by 18.9% (p = 0.024); in addition, there was 22.5% risk reduction in the composite of myocardial infarction and death. The risk reduction in the composite endpoint at 7 days, 30 days and 6 months is shown in the Kaplan-Meier curve in Figure 1.
In the 30% of patients who underwent angioplasty/atherectomy in the PRISM PLUS study, there was a 45.7% risk reduction in the composite endpoint following the procedure at day 30 after start of study drug, as well as a 43.2% risk reduction in the composite of death and myocardial infarction.
A substudy in PRISM PLUS found that there was a significant decrease in the extent of angiographically apparent thrombus in patients treated with Aggrastat in combination with heparin compared to heparin alone. In addition, flow in the affected coronary artery was significantly improved.
PRISM PLUS was not designed to provide definitive results in subsets of the overall population. Nonetheless, demographic results were examined for age, gender and race. No difference in benefit was noticed for age and gender but too few non-Caucasians were enrolled to make a definite statement about racial differences in treatment effect.

PRISM (platelet receptor inhibition for ischaemic syndrome management).

In the PRISM study, a randomised, parallel, double blind, active control study, Aggrastat alone (n = 1,616) was compared to heparin (n = 1,616) alone as medical management in patients with unstable angina/non-Q wave myocardial infarction. In this study, the drug was started within 24 hours of the time the patient experienced chest pain.
Patients were randomised to either Aggrastat alone (30 minute loading dose of 0.6 microgram/kg/minute, followed by a maintenance infusion of 0.15 microgram/kg/minute) or heparin alone (bolus of 5,000 U followed by an infusion of 1,000 U/hour titrated to maintain an APTT of approximately 2 times control). The mean age of the population was 62 years; 32% of the population was female and 25% had non-Q wave myocardial infarction on presentation. Thirty percent had no ECG evidence of cardiac ischaemia. Exclusion criteria were similar to PRISM PLUS. The primary, prospectively identified endpoint was the composite endpoint of refractory ischaemia, myocardial infarction or death after a 48 hour drug infusion with Aggrastat. The results are shown in Table 4.
In the PRISM study, no adverse effect of Aggrastat on mortality at either 7 or 30 days was detected.

5.2 Pharmacokinetic Properties

Distribution.

Tirofiban is not highly bound to plasma proteins and protein binding is concentration independent over the range of 0.01 to 25 microgram/mL. Unbound fraction in human plasma is 35%. The steady-state volume of distribution of tirofiban ranges from 22 to 42 litres.

Metabolism.

Profiling of 14C-labelled tirofiban in urine and faeces indicates that the radioactivity was accounted for mainly by unchanged tirofiban. Circulating plasma radioactivity is accounted for mainly by unchanged tirofiban (up to 10 hours postdose). These data suggest limited metabolism of tirofiban.

Excretion.

Following an intravenous dose of 14C-labelled tirofiban in healthy subjects, 66% of radioactivity is recovered in the urine and 23% in the faeces. Total radioactivity recovery is about 91%. Both urinary and biliary excretion contribute significantly to the elimination of tirofiban.
In healthy subjects, the plasma clearance of tirofiban ranges from 213 to 314 mL/minute. Renal clearance accounts for 39 to 69% of plasma clearance. Half-life ranges from 1.4 to 1.8 hours.
In patients with coronary artery disease, the plasma clearance of tirofiban ranges from 152 to 267 mL/minute. Renal clearance accounts for 39% of plasma clearance. Half-life ranges from 1.9 to 2.2 hours.
Plasma clearance of tirofiban in patients with coronary artery disease is similar in males and females.
Plasma clearance of tirofiban is about 19 to 26% lower in elderly (> 65 years) patients with coronary artery disease compared to younger (≤ 65 years) patients.
No difference in plasma clearance was detected in patients of different races.
In patients with mild to moderate hepatic insufficiency, plasma clearance of tirofiban is not significantly different compared to healthy subjects.
Plasma clearance of tirofiban is lower to a clinically significant extent (> 50%) in patients with creatinine clearance < 30 mL/minute, including patients requiring haemodialysis (see Section 4.2 Dose and Method of Administration, Patients with severe renal insufficiency). Tirofiban is removed by haemodialysis.

5.3 Preclinical Safety Data

Genotoxicity.

Tirofiban was not genotoxic in a series of assays for gene mutations (Salmonella typhimurium, Escherichia coli and Chinese hamster lung cells), chromosomal aberrations (Chinese hamster ovary cell in vitro and mouse bone marrow in vivo) or DNA damage (alkaline elution assay).

Carcinogenicity.

The carcinogenic potential of tirofiban hydrochloride has not been evaluated.

6 Pharmaceutical Particulars

6.1 List of Excipients

Each mL of the solution contains the following inactive ingredients: 0.16 mg citric acid, 2.7 mg sodium citrate dihydrate and 8 mg sodium chloride and water for injections.

6.2 Incompatibilities

Incompatibilities were either not assessed or not identified as part of the registration of this medicine.

6.3 Shelf Life

In Australia, information on the shelf life can be found on the public summary of the Australian Register of Therapeutic Goods (ARTG). The expiry date can be found on the packaging.

6.4 Special Precautions for Storage

Aggrastat Concentrate for Infusion 0.25 mg/mL 50 mL glass vials: Store below 30°C. Do not freeze. Protect from light during storage.
Must be diluted prior to administration (see Section 4.2 Dose and Method of Administration, Instructions for use), to give a concentration of 0.05 mg/mL.

6.5 Nature and Contents of Container

Aggrastat Concentrate for Infusion is supplied in a 50 mL glass vial.

6.6 Special Precautions for Disposal

In Australia, any unused medicine or waste material should be disposed of by taking to your local pharmacy.

6.7 Physicochemical Properties

Tirofiban hydrochloride monohydrate is chemically described as N-(butylsulfonyl)-O-[4-(4- piperidinyl)butyl]-L-tyrosine monohydrochloride monohydrate.
Tirofiban hydrochloride monohydrate is a white to off-white non-hygroscopic free-flowing powder, with a molecular weight of 495.08. It is very slightly soluble in water.

Chemical structure.

Its empirical formula is C22H36N2O5S.HCl.H2O, and its structural formula is:

CAS number.

150915-40-5.

7 Medicine Schedule (Poisons Standard)

S4.

Summary Table of Changes