Consumer medicine information

1. Why am I being treated with Atgam?

Atgam contains the active ingredient, equine antithymocyte immunoglobulin. It is a type of horse protein used to help control your body's immune system to foreign protein. Atgam is used after a kidney transplant to stop your body's immune system from rejecting the new kidney. For more information, see Section 1. Why am I being treated with Atgam? in the full CMI.

2. What should I know before treatment with Atgam?

Do not use if you have ever had an allergic reaction to Atgam/equine antithymocyte immunoglobulin or other horse proteins (equine gamma globulins) or any of the ingredients listed at the end of the CMI.
It is possible for products developed from horse or human blood to carry infectious diseases like viral hepatitis and AIDS.
Talk to your doctor if you have any other medical conditions, take any other medicines, or if you are pregnant or plan to become pregnant or are breastfeeding. For more information, see Section 2. What should I know before treatment with Atgam? in the full CMI.

3. What if I am taking other medicines?

Some medicines may interfere with Atgam and affect how it works.
More instructions can be found in Section 3. What if I am taking other medicines? in the full CMI.

4. How is Atgam given?

Atgam will be given to you by your doctor usually after skin testing. It is diluted and given by slow infusion into a vein over a period of at least 4 hours. You will be monitored during treatment in case you have an allergic reaction to Atgam. If you have an allergic reaction, treatment with Atgam will be stopped. You may need to have regular checks for new infections.
More instructions can be found in Section 4. How is Atgam given? in the full CMI.

5. What should I know during treatment with Atgam?

6. Are there any side effects?

Side effects include swollen face, lips, tongue, difficulty breathing, hives (anaphylaxis); fever, chills, sore mouth/throat, feeling unwell or tired; cold sores, eye or genital infections; cough; hiccups; throat muscle spasms; pain, swelling/redness at injection site; nosebleed; surgical wounds not healing; sweating/night sweats; stomach pain; loss of appetite; nausea; vomiting; diarrhoea; constipation; skin rash, itchiness, blisters, peeling skin; dizziness; feeling faint; confusion; hallucinations; convulsions; headache; swollen feet/leg or around eyes; swollen lymph gland; swollen tonsils; leg or joint pain; low or high blood pressure; fast or slow heart rate; purplish, bulging veins; aching muscles; tingling sensation; paralysis; abnormal movement/tremor/rigidity; chest pain when breathing; difficulty speaking, light sensitivity; lower back or side pain; coloured or blood in stools; dark or blood in urine, change to urine frequency or volume; bruising or bleeding easily; blood, liver or kidney problems showing as abnormal blood test results.
For more information, including what to do if you have any side effects, see Section 6. Are there any side effects? in the full CMI.

Boxed Warnings

In common with products derived from, or purified with equine and human blood components, the possibility of transmission of infectious diseases, including viral hepatitis, human immunodeficiency virus (HIV - the causative agent for AIDS or acquired immuno-deficiency syndrome), and theoretically, the Creutzfeldt-Jakob disease (CJD) agent must always be considered, and should be conveyed to patients who may receive the product.

1 Name of Medicine

Equine antithymocyte immunoglobulin.

2 Qualitative and Quantitative Composition

Each 5 mL ampoule of Atgam contains 250 mg of horse gamma globulin (equine antithymocyte immunoglobulin) stabilised in 0.3 molar glycine to a pH of approximately 6.8 (pH range 6.4 - 7.2).
Atgam is the purified, concentrated and sterile gamma globulin, primarily monomeric IgG, from hyperimmune serum of horses immunised with human thymus lymphocytes.
Before release for clinical use, each Atgam lot is tested for its ability to inhibit rosette formation between human peripheral lymphocytes and sheep red blood cells in vitro. The potency of lots may vary over a twelve-fold range. The clinical significance of this is unknown.
Atgam is not solely anti-human thymocyte globulin.
Atgam is likely to contain low levels of antibodies against other formed elements of the blood and also other antibodies raised by the horse in response to prior antigenic exposure. These may include pertussis, tetanus, influenza, mycobacterium, equine encephalomyelitis or strangles.
During processing, the drug is adsorbed with human erythrocyte stroma and with IgG-free human plasma proteins to reduce or remove antibodies against human red blood cells and human plasma proteins. Each lot is tested before release to assure that antibody activity against platelets is within acceptable limits. Each lot of Atgam must also test negative for anti-human serum protein antibody and anti-glomerular basement membrane before release.
No preservative or antimicrobial agent added.
For the full list of excipients, see Section 6.1 List of Excipients.

3 Pharmaceutical Form

Solution for injection. To be diluted prior to intravenous infusion.
Atgam is a transparent to slightly opalescent, colourless to light brown solution. It may develop a slight granular or flaky deposit during storage.

4 Clinical Particulars

4.9 Overdose

Because of its mode of action and because it is a biological substance, the maximum tolerated dose of Atgam would be expected to vary from patient to patient. To date, the largest single daily dose administered to one patient (renal transplant recipient) was 7,000 mg administered at a concentration of approximately 10 mg/mL of saline, seven times the recommended total dose and infusion concentration. In this patient, administration of Atgam was not associated with any signs of acute intoxication or late sequelae.
The greatest number of doses (10 to 20 mg/kg/dose) that can be administered to a single patient has not yet been determined. Some renal transplant patients have received up to 50 doses in 4 months, and others have received 28-day courses of 21 doses followed by as many as 3 more courses for the treatment of acute rejection. The incidence of toxicological manifestations did not increase with any of these regimens, however close monitoring of the patient is recommended.
For information on the management of overdose, contact the Poisons Information Centre on 13 11 26 (Australia).
Caution. Atgam is available only to hospital units which are equipped and staffed for transplant surgery.

5 Pharmacological Properties

5.3 Preclinical Safety Data

In the routine development of Atgam, aliquots of the various clinical lots have been infused intravenously to either Macaca rhesus or Macaca irus monkeys. Two dosage regimens have been used: 100 mg/kg on day 0, 200 mg/kg on day 2 and 400 mg/kg on day 4 or, currently, 50 mg/kg on days 0, 2, 4 and 7. A three week observation period has followed the last infusion in either dosage regimen. These studies do not fully explore the toxicological potential of Atgam.
The observed changes could have been anticipated on the basis of the anti-lymphocyte activity with Atgam. Within 24 hours after infusion, decreased peripheral blood lymphocytes and increased total leukocyte and neutrophil counts occurred. Decreased thymus size with involution or atrophy or both and decreased lymphocyte populations in the thymus-dependent areas of the spleen and lymph nodes were noted. The atrophy was most prevalent in animals that received the higher doses.
In animals receiving either dosage regimen, packed cell volume, total erythrocyte counts, and haemoglobin concentrations have decreased, and reticulocytes and nucleated erythrocytes have increased enough to be classified as anaemia. An occasional death believed to have resulted from anaemia has occurred.
Transient decreases in blood platelet counts have also occurred. Thrombus formation occurred frequently along the routes of infusion, i.e. the saphenous and femoral veins. However, the incidence of thrombi has decreased since inline filters have been used during infusion. In these animals no evidence of DIC (disseminated intravascular coagulation) has appeared.
Genotoxicity. Non-clinical data reveal no special hazard identified for humans based on conventional studies of repeated dose toxicity and genotoxicity.
Carcinogenicity. Carcinogenicity and pre-/post-natal development studies have not been conducted on Atgam.

6 Pharmaceutical Particulars

6.7 Physicochemical Properties

Chemical structure. No data available.
CAS number. No data available.

7 Medicine Schedule (Poisons Standard)

Prescription Only Medicine (Schedule 4).

Summary Table of Changes

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