Anaphylactic or anaphylactoid reactions have occurred with Trasylol® administration, including fatal reactions in association with the initial (test) dose. The initial (test) dose does not fully predict a patient’s risk for a hypersensitivity reaction, including a fatal reaction. Fatal hypersensitivity reactions have occurred among patients who tolerated an initial (test) dose.
Hypersensitivity reactions often manifest as anaphylactic/anaphylactoid reactions with hypotension the most frequently reported sign of the hypersensitivity reaction. The hypersensitivity reaction can progress to anaphylactic shock with circulatory failure. If a hypersensitivity reaction occurs during injection or infusion of Trasylol®, administration should be stopped immediately and emergency treatment should be initiated. Even when a second exposure to aprotinin has been tolerated without symptoms, a subsequent administration may result in severe hypersensitivity/anaphylactic reactions.
Trasylol® should be administered only in operative settings where cardiopulmonary bypass can be rapidly initiated. Before initiating treatment with Trasylol®, the recommendations below should be followed to manage a potential hypersensitivity or anaphylactic reaction: 1) Have standard emergency treatments for hypersensitivity or anaphylactic reactions readily available in the operating room (e.g., epinephrine, corticosteroids). 2) Administration of the initial (test) dose and loading dose should be done only when the patient is intubated and when conditions for rapid cannulation and initiation of cardiopulmonary bypass are present. 3) Delay the addition of Trasylol® into the pump prime solution until after the loading dose has been safely administered.
Re-exposure to aprotinin: Administration of aprotinin, especially to patients who have received aprotinin in the past, requires a careful risk/benefit assessment because an allergic reaction may occur (see CONTRAINDICATIONS). Although the majority of cases of anaphylaxis occur upon re-exposure within the first 12 months, there are also case reports of anaphylaxis occurring upon re-exposure after more than 12 months.
In a retrospective review of 387 European patient records with documented re-exposure to Trasylol®, the incidence of hypersensitivity/anaphylactic reactions was 2.7%. Two patients who experienced hypersensitivity/anaphylactic reactions subsequently died, 24 hours and 5 days after surgery, respectively. The relationship of these 2 deaths to Trasylol® is unclear. This retrospective review also showed that the incidence of a hypersensitivity or anaphylactic reaction following re-exposure is increased when the re-exposure occurs within 6 months of the initial administration (5.0% for re-exposure within 6 months and 0.9% for re-exposure greater than 6 months). Other smaller studies have shown that in case of re-exposure, the incidence of hypersensitivity/anaphylactic reactions may reach the five percent level.
An analysis of all spontaneous reports from the Bayer Global database covering a period from 1985 to March 2006 revealed that of 291 possibly associated spontaneous cases of hypersensitivity (fatal: n=52 and non-fatal: n=239), 47% (138/291) of hypersensitivity cases had documented previous exposure to Trasylol®. Of the 138 cases with documented previous exposure, 110 had information on the time of the previous exposure. Ninety-nine of the 110 cases had previous exposure within the prior 12 months.
Renal Dysfunction: Trasylol® administration increases the risk for renal dysfunction and may increase the need for dialysis in the perioperative period. This risk may be especially increased for patients with pre-existing renal impairment or those who receive aminoglycoside antibiotics or drugs that alter renal function. Data from Bayer’s global pool of placebo-controlled studies in patients undergoing coronary artery bypass graft (CABG) surgery showed that the incidence of serum creatinine elevations >0.5 mg/dL above pre-treatment levels was statistically higher at 9.0% (185/2047) in the high-dose aprotinin (Regimen A) group compared with 6.6% (129/1957) in the placebo group. In the majority of instances, post-operative renal dysfunction was not severe and was reversible. However, renal dysfunction may progress to renal failure and the incidence of serum creatinine elevations >2.0 mg/dL above baseline was slightly higher in the high-dose aprotinin group (1.1% vs. 0.8%). Careful consideration of the balance of benefits versus potential risks is advised before administering Trasylol® to patients with impaired renal function (creatinine clearance < 60 mL/min) or those with other risk factors for renal dysfunction (such as perioperative administration of aminogylcoside or products that alter renal function). (See PRECAUTIONS and ADVERSE REACTIONS: Laboratory Findings: Serum Creatinine.)
Initial (Test) Dose: All patients treated with Trasylol® should first receive an initial (test) dose to minimize the extent of Trasylol® exposure and to help assess the potential for allergic reactions. Initiation of this initial (test) dose should occur only in operative settings where cardiopulmonary bypass can be rapidly initiated. The initial (test) dose of 1 mL Trasylol® should be administered intravenously at least 10 minutes prior to the loading dose and the patient should be observed for manifestations of possible hypersensitivity reaction. However, even after the uneventful administration of the initial 1 mL (test) dose, any subsequent dose may cause an anaphylactic reaction. If this happens, the infusion of Trasylol® should immediately be stopped and standard emergency treatment for anaphylaxis applied. It should be noted that serious, even fatal, hypersensitivity/anaphylactic reactions can also occur with administration of the initial (test) dose (see WARNINGS).
Allergic Reactions: Patients with a history of allergic reactions to drugs or other agents may be at greater risk of developing a hypersensitivity or anaphylactic reaction upon exposure to Trasylol® (see WARNINGS).
Loading Dose: The loading dose of Trasylol® should be given intravenously to patients in the supine position over a 20-30 minute period. Rapid intravenous administration of Trasylol® can cause a transient fall in blood pressure (see DOSAGE AND ADMINISTRATION).
Renal Dysfunction: Bayer’s global pool of placebo-controlled studies in patients undergoing CABG showed aprotinin administration was associated with elevations of serum creatinine values > 0.5 mg/dL above baseline. Careful consideration of the balance of benefits and risks is advised before administering aprotinin to patients with pre-existing impaired renal function or those with other risk factors for renal dysfunction. Serum creatinine should be monitored regularly following Trasylol® administration (see WARNINGS: Renal Dysfunction).
Use of Trasylol® in patients undergoing deep hypothermic circulatory arrest: Two U.S. case control studies have reported contradictory results in patients receiving Trasylol® while undergoing deep hypothermic circulatory arrest in connection with surgery of the aortic arch.
The first study showed an increase in both renal failure and mortality compared to age-matched historical controls. Similar results were not observed, however, in a second case control study. The strength of this association is uncertain because there are no data from randomized studies to confirm or refute these findings.
Trasylol® is known to have antifibrinolytic activity and, therefore, may inhibit the effects of fibrinolytic agents.
In study of nine patients with untreated hypertension, Trasylol® infused intravenously in a dose of 2 million KIU over two hours blocked the acute hypotensive effect of 100mg of captopril.
Trasylol®, in the presence of heparin, has been found to prolong the activated clotting time (ACT) as measured by a celite surface activation method. The kaolin activated clotting time appears to be much less affected. However, Trasylol® should not be viewed as a heparin sparing agent (see Laboratory Monitoring of Anticoagulation During Cardiopulmonary Bypass).
Carcinogenesis, Mutagenesis, Impairment of Fertility:
Long-term animal studies to evaluate the carcinogenic potential of Trasylol® or studies to determine the effect of Trasylol® on fertility have not been performed.
Results of microbial in vitro tests using Salmonella typhimurium and Bacillus subtilis indicate that Trasylol® is not a mutagen.
Pregnancy: Teratogenic Effects: Pregnancy Category B:
Reproduction studies have been performed in rats at intravenous doses up to 200,000 KIU/kg/day for 11 days, and in rabbits at intravenous doses up to 100,000 KIU/kg/day for 13 days, 2.4 and 1.2 times the human dose on a mg/kg basis and 0.37 and 0.36 times the human mg/m2 dose. They have revealed no evidence of impaired fertility or harm to the fetus due to Trasylol®. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Safety and effectiveness in pediatric patient(s) have not been established.
Of the total of 3083 subjects in clinical studies of Trasylol®, 1100 (35.7 percent) were 65 and over, while 297 (9.6 percent) were 75 and over. Of patients 65 years and older, 479 (43.5 percent) received Regimen A and 237 (21.5 percent) received Regimen B. No overall differences in safety or effectiveness were observed between these subjects and younger subjects for either dose regimen, and other reported clinical experience has not identified differences in responses between the elderly and younger patients.
Laboratory Monitoring of Anticoagulation during Cardiopulmonary Bypass:
Trasylol® prolongs whole blood clotting times by a different mechanism than heparin. In the presence of aprotinin, prolongation is dependent on the type of whole blood clotting test employed. If an activated clotting time (ACT) is used to determine the effectiveness of heparin anticoagulation, the prolongation of the ACT by aprotinin may lead to an overestimation of the degree of anticoagulation, thereby leading to inadequate anticoagulation. During extended extracorporeal circulation, patients may require additional heparin, even in the presence of ACT levels that appear adequate.
In patients undergoing CPB with Trasylol® therapy, one of the following methods may be employed to maintain adequate anticoagulation:
- 1) ACT - An ACT is not a standardized coagulation test, and different formulations of the assay are affected differently by the presence of aprotinin. The test is further influenced by variable dilution effects and the temperature experienced during cardiopulmonary bypass. It has been observed that Kaolin-based ACTs are not increased to the same degree by aprotinin as are diatomaceous earth-based (celite) ACTs. While protocols vary, a minimal celite ACT of 750 seconds or kaolin-ACT of 480 seconds, independent of the effects of hemodilution and hypothermia, is recommended in the presence of aprotinin. Consult the manufacturer of the ACT test regarding the interpretation of the assay in the presence of Trasylol®.
- 2)Fixed Heparin Dosing - A standard loading dose of heparin, administered prior to cannulation of the heart, plus the quantity of heparin added to the prime volume of the CPB circuit, should total at least 350 IU/kg. Additional heparin should be administered in a fixed-dose regimen based on patient weight and duration of CPB.
- 3) Heparin Titration - Protamine titration, a method that is not affected by aprotinin, can be used to measure heparin levels. A heparin dose response, assessed by protamine titration, should be performed prior to administration of aprotinin to determine the heparin loading dose. Additional heparin should be administered on the basis of heparin levels measured by protamine titration. Heparin levels during bypass should not be allowed to drop below 2.7 U/mL (2.0 mg/kg) or below the level indicated by heparin dose response testing performed prior to administration of aprotinin.
Protamine Administration - In patients treated with Trasylol®, the amount of protamine administered to reverse heparin activity should be based on the actual amount of heparin administered, and not on the ACT values.