Traceability
In order to improve the traceability of biological medicinal products, the name and the batch number of the administered product should be clearly recorded.
GAMMAGARD S/D is not indicated in patients with selective IgA deficiency where the IgA deficiency is the only abnormality of concern.
GAMMAGARD S/D should only be administered intravenously.
GAMMAGARD S/D is reconstituted to provide a protein solution of 5 g per 100 mL of solvent. This fluid volume will result in blood volume expansion with the extent dependent on the dose administered. When administered in high dose over a relatively short period of time, signs and symptomatology of fluid overload may result, especially in susceptible patients such as small children, elderly individuals or patients with renal impairment.
Certain severe adverse drug reactions such as headache and flushing may be related to the rate of infusion. Slowing or stopping the infusion usually allows the symptoms to disappear promptly. The infusion may then be resumed at a rate that does not result in recurrence of the symptoms. (see section 4.8).
The recommended infusion rate given under "4.2 Method of Administration" must be closely followed. Patients must be closely monitored and carefully observed for any symptoms throughout the infusion period. Certain adverse reactions may occur more frequently
- in case of high rate of infusion;
- in patients with hypo- or agammaglobulinemia with or without IgA deficiency;
- in immunodeficient patients who receive human normal immunoglobulin for the first time, or in rare cases, when the human normal immunoglobulin product is switched or when there has been a long interval since the previous infusion.
Hypersensitivity
True hypersensitivity reactions are rare. They can occur in the very seldom cases of IgA deficiency with anti-IgA antibodies. Rarely, human normal immunoglobulin can induce an anaphylactic reaction with a fall in blood pressure with anaphylactic reaction, even in patients who had tolerated previous treatment with human normal immunoglobulin.
Patients with antibodies to IgA or with IgA deficiencies that are a component of an underlying primary immunodeficiency disease for which IVIG treatment is indicated may be at increased risk of anaphylactic reaction. Anaphylaxis has been reported with the use of GAMMAGARD S/D even though it contains low levels of IgA. (see section 4.8)
GAMMAGARD S/D is not indicated in patients with selective IgA deficiency where the IgA deficiency is the only abnormality of concern. These patients should be treated only if their IgA deficiency is associated with an immune deficiency for which therapy with intravenous immune globulin is clearly indicated.
Patients who have had a severe hypersensitivity reaction to other intravenous gammaglobulin preparations should only receive GAMMAGARD S/D with utmost caution and in a setting where supportive care is available for treating life-threatening reactions (see section 4.8).
Potential complications can often be avoided by ensuring:
- that patients are not sensitive to human normal immunoglobulin by initially injecting the product slowly (0.5 mL/kg/hour);
- that patients are carefully monitored for any symptoms throughout the infusion period. In particular, patients naïve to human normal immunoglobulin, patients switched from an alternative IVIg product or when there has been a long interval since the previous infusion should be monitored during the first infusion and for the first hour after the first infusion, in order to detect potential adverse signs. All other patients should be observed for at least 20 minutes after administration;
- that the glucose content (max. content of 0.4g/g of IgG) is taken into account in case of latent diabetes (where transient glycosuria could appear), diabetes, or in patients on a low sugar diet.
Thrombolembolism
There is clinical evidence of an association between IVIG treatment (including GAMMMAGARD S/D), and thromboembolic events such as myocardial infarction, stroke, pulmonary embolism and deep vein thromboses which is assumed to be related to a relative increase in blood viscosity through the high influx of immunoglobulin in at-risk patients. Caution should be exercised in prescribing and infusing IVIg in obese patients and in patients with pre-existing risk factors for thrombotic events (such as history of atherosclerosis, multiple cardiovascular risk factors, advanced age, impaired cardiac output, known or suspected hyperviscosity, for example dehydration or paraproteins, hypercoagulable disorders, prolonged period of immobilization, obesity, diabetes mellitus, patients using oestrogens, patients with an indwelling vascular catheter acquitted or inherited thrombophilic disorder, a dose and rapid infusion.).
In patients at risk of hyperviscosity monitor for signs and symptoms of thrombosis and assess blood viscosity.
Acute renal failure
Severe renal adverse reactions have been reported in patients receiving IVIG treatment, particularly those products containing sucrose (GAMMAGARD S/D does not contain sucrose). These include
- acute renal failure (reported with GAMMAGARD S/D)
- acute tubular necrosis
- proximal tubular nephropathy
- osmotic nephrosis
In most cases, risk factors have been identified, such as pre-existing renal insufficiency, diabetes mellitus, hypovolemia, hyperviscosity, concomitant nephrotoxic medicinal products, age over 65 years, sepsis or paraprotinaemia.
In cases of renal impairment, IVIg discontinuation should be considered. While these reports of renal dysfunction and acute renal failure have been associated with the use of many of the licensed IVIg products, those containing sucrose as a stabilizer accounted for a disproportionate share of the total number. In patients at risk, the use of IVIg products that do not contain sucrose may be considered.
In patients at risk for acute renal failure or thromboembolic adverse reactions, IVIg products should be administered at the minimum rate of infusion and dose practicable.
In all patients IVIg administration requires:
- adequate hydration prior to and after initiation of the infusion of IVIg
- monitoring of urine output
- monitoring of serum creatinine levels
- avoidance of concomitant use of loop diuretics.
In case of adverse reaction, either the rate of administration must be reduced, or the infusion stopped. The treatment required depends on the nature and severity of the side effect. In case of shock, standard medical treatment for shock should be implemented.
Transfusion Related Acute Lung Injury
There have been reports of noncardiogenic pulmonary oedema (Transfusion Related Acute Lung Injury, TRALI) in patients administered IVIG.
Interference with Laboratory Tests
After infusion of immunoglobulin, the transitory rise of the various passively transferred antibodies in the patient´s blood may result in misleading positive results in serological testing for example Hepatitis A, Hepatitis B, measles and varicella.
Passive transmission of antibodies to erythrocyte antigens e.g. A, B, D may interfere with some serological tests for red cell antibodies, for example the antiglobulin test (direct Coombs test).
Administration of GAMMAGARD S/D can lead to false positive readings in assays that depend on detection of beta-D-glucans for diagnosis of fungal infections; this may persist during the weeks following infusion of the product.
Transmissible agents
GAMMAGARD S/D is made from human plasma. Standard measures to prevent infections resulting from the use of medicinal products prepared from human blood or plasma include selection of donors, screening of individual donations and plasma pools for specific markers of infection and the inclusion of effective manufacturing steps for the inactivation/removal of viruses. Despite this, when medicinal products prepared from human blood or plasma are administered, the possibility of transmitting infective agents cannot be totally excluded. This also applies to unknown or emerging viruses and other pathogens, such as the Creutzfeldt-Jacob disease (CJD) agent.
The measures taken are considered effective for enveloped viruses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV), and for the non-enveloped viruses hepatitis A (HAV) and parvovirus B19 viruses.
There is reassuring clinical experience regarding the lack of hepatitis A or parvovirus B19 transmission with immunoglobulins and it is also assumed that the antibody content makes an important contribution to the viral safety.
Further precautions
Hyperproteinaemia and increased serum viscosity may occur in patients receiving IVIG therapy.
Gammagard S/D contains blood group antibodies that may act as haemolysins and induce in vivo coating of red blood cells (RBC) with immune globulin. This may cause a positive direct antiglobulin test [DAT (Coombs test)]. Delayed haemolytic anaemia can develop subsequent to GAMMAGARD S/D therapy due to enhanced RBC sequestration; acute haemolysis, consistent with intravascular haemolysis, has been reported.
The following risk factors may be related to the development of haemolysis: high doses (single administration or divided over several days) and non-O blood group. Underlying inflammatory state in an individual patient may increase the risk of haemolysis but its role is uncertain.
Hyperproteinaemia and increased serum viscosity may occur in patients receiving IVIG therapy.
Sodium content
This medicinal product contains 668 mg sodium per bottle (10 g), equivalent to 34% of the WHO recommended maximum daily intake of 2 g sodium for an adult.