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HomeEfficacyEfficacyAplastic AnemiaRenal Allograft RejectionSafetyDosing & Administration
Prescribing Information, including BOXED WARNINGIndications
SafetySafetyATGAM safety profile in moderate to severe aplastic anemia and renal allograft rejection.1ATGAM safety profile in moderate to severe aplastic anemia and renal allograft rejection.1Boxed warning1

Anaphylaxis has been reported with the use of ATGAM. ATGAM can cause potentially
life-threatening anaphylaxis when injected intravenously. Monitor patients for signs and symptoms of anaphylaxis during infusion and for at least 24 hours after infusion.

Adverse reactions1

The most commonly reported adverse reactions (occurring in greater than 10% of patients) were pyrexia, chills, rash, thrombocytopenia, leukopenia, and arthralgia.

Contraindications1

Do not administer ATGAM to a patient who has had an anaphylactic reaction during prior administration of ATGAM or any other equine gamma globulin preparation.

Warnings and precautions for use1

Adverse reactions reported in clinical studies and published reports1

Thrombocytopenia

Rash

Arthralgia

Pyrexia

Chills

Anaphylaxis

Anaphylaxis has been reported with the use of ATGAM. Anaphylaxis is potentially life-threatening. Discontinue ATGAM if anaphylaxis occurs. Generalized rash, tachycardia, dyspnea, and hypotension can be signs of an anaphylactic reaction.
 

  • Skin Testing

    • To identify those at greatest risk of systemic anaphylaxis, skin testing potential recipients is strongly recommended before commencing treatment. Consult an allergist for epicutaneous (prick) and intradermal testing and interpretation. Positive skin testing to ATGAM suggests clinical hypersensitivity and increased risk of a systemic allergic reaction (including anaphylaxis) should the drug be dosed intravenously. In the event of a positive skin test, seriously consider alternative forms of therapy. The predictive value of this test has not been proven clinically, and allergic reactions such as anaphylaxis have occurred in patients whose skin tests were negative. It is important to note that skin testing does not inform risk of delayed hypersensitivity reactions such as serum sickness
  • Monitoring and Management of Anaphylaxis

    • Administer ATGAM in a healthcare facility where a physician familiar with the treatment of potentially life-threatening allergic reactions is in attendance. Monitor patients for signs and symptoms of anaphylaxis during infusion and for at least 24 hours after infusion of ATGAM. Have epinephrine and emergency equipment available for treatment of acute allergic symptoms, should they occur 
Cytokine Release Syndrome

Cytokine release syndrome has been reported with the use of ATGAM. Cytokine release syndrome can be fatal. Clinical signs may include fever, chills, headache, chest pain, hypotension, dyspnea, tachypnea, and edema. Monitor patients for signs and symptoms of cytokine release syndrome and manage according to relevant clinical guidelines.

Infusion-Associated Reactions

Serious infusion-associated reactions have been reported with the use of ATGAM. Clinical signs associated with infusion-associated reactions include generalized rash, tachycardia, dyspnea, and hypotension. Monitor patients for signs and symptoms of infusion-associated reactions and manage according to relevant clinical guidelines.

Serum Sickness

Serum sickness is a delayed hypersensitivity/immune reaction. Symptoms of serum sickness including rash, arthralgia, pyrexia, chills, and pain have been reported. Monitor patients for signs and symptoms of serum sickness and manage according to relevant clinical guidelines.

Transmissible Infectious Agents

Because ATGAM is made from equine and human blood components, it may carry a risk of transmitting infectious agents, eg, viruses and the Creutzfeldt-Jakob disease (CJD) agent. This also applies to unknown or emerging viruses and other pathogens. Report any infection suspected to have been transmitted by this product to Pfizer Inc. at 1-800-438-1985.

Infections

Due to the immunosuppressive effects of ATGAM, opportunistic infections (viral, bacterial, and fungal) have been reported. Sepsis has also been reported. There is an increased risk of viral reactivation (eg, cytomegalovirus [CMV], Epstein–Barr virus [EBV] infection, herpes simplex virus [HSV]). Monitor patients carefully for concurrent infection.

Immunizations

Do not administer live vaccines to patients about to receive, receiving, or after treatment with ATGAM. Concomitant administration of ATGAM with live virus vaccines carries a potential of uncontrolled viral replication in the immunosuppressed patient. There is insufficient information to fully define the extent of the risk, or the period of time during which the risk exists. If administered, live viruses may interfere with ATGAM treatment.

Thrombocytopenia and Neutropenia

Thrombocytopenia and neutropenia have been reported with the use of ATGAM. If thrombocytopenia occurs, consider platelet transfusions to maintain platelets at clinically acceptable levels. Consider discontinuing ATGAM if severe and unremitting thrombocytopenia or neutropenia occurs.

Hepatic and Renal Function Tests

In patients with aplastic anemia and other hematologic abnormalities who have received ATGAM, abnormal test results of liver function (SGOT, SGPT, alkaline phosphatase) and renal function (serum creatinine) have been observed. Monitor liver and renal functions as clinically indicated and manage according to relevant clinical guidelines.

Special considerations for particular types of patient groups when using ATGAM1

Pediatric patients
  • Although clinical experience with children has been limited, ATGAM has been administered safely to a small number of pediatric renal allograft recipients and pediatric aplastic anemia patients at dosage levels comparable to those in adults
Geriatric patients
  • Clinical experience in a limited number of elderly patients (≥65 years of age) has not identified differences in responses between the elderly and younger patients
Pregnant patients
  • Clinical experience with ATGAM is limited in pregnant or lactating patients, therefore ATGAM should be used only if the potential benefit to the patient justifies the potential risk to the fetus

  • Patients of reproductive potential should use effective contraception during treatment with ATGAM and for at least 10 weeks after cessation of therapy
Reference:ATGAM [prescribing information]. New York, NY: Pfizer Inc., May 2023. Explore ATGAM Efficacy Efficacy Loading Learn About ATGAM Dosing & Administration Dosing & Administration Loading ATGAM Ordering and Availability Information View Ordering and Availability Information Loading

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ATGAM® (lymphocyte immune globulin, anti-thymocyte globulin [equine]) INDICATIONS

ATGAM is indicated for:
 
  • Management of allograft rejection in renal transplant patients; when administered with conventional therapy at the time of rejection ATGAM increases the frequency of resolution of the acute rejection episode.
  • Treatment of moderate to severe aplastic anemia in patients unsuitable for bone marrow transplantation.

LIMITATIONS OF USE

The usefulness of ATGAM has not been demonstrated in patients with aplastic anemia who are suitable candidates for bone marrow transplantation or in patients with aplastic anemia secondary to neoplastic disease, storage disease, myelofibrosis, Fanconi's syndrome, or in patients known to have been exposed to myelotoxic agents or radiation.

Please see full Prescribing Information, including BOXED WARNING.
IMPORTANT SAFETY INFORMATION WARNING: ANAPHYLAXIS

Anaphylaxis has been reported with the use of ATGAM. ATGAM can cause potentially life-threatening anaphylaxis when injected intravenously. Monitor patients for signs and symptoms of anaphylaxis during infusion and for at least 24 hours after infusion.

Contraindications
Do not administer ATGAM to a patient who has had an anaphylactic reaction during prior administration of ATGAM or any other equine gamma globulin preparation.

Warnings and Precautions

Anaphylaxis: Discontinue ATGAM if anaphylaxis occurs.
  • Skin testing: To identify those at greatest risk, skin testing before treatment is strongly recommended.
  • Monitoring and Management of Anaphylaxis: Administer ATGAM in a healthcare facility where a physician familiar with the treatment of potentially life-threatening allergic reactions is in attendance. Monitor patients for signs and symptoms of anaphylaxis during infusion and for at least 24 hours after infusion of ATGAM.
Cytokine Release Syndrome: Monitor patients for signs and symptoms of cytokine release syndrome and manage according to relevant clinical guidelines. 

Infusion-Associated Reactions: Monitor patients for signs and symptoms of infusion-associated reactions and manage according to relevant clinical guidelines.


Serum Sickness: Monitor patients for signs and symptoms of serum sickness and manage according to relevant clinical guidelines.
 

Transmissible Infectious Agents: Because ATGAM is made from equine and human blood components, it may carry a risk of transmitting infectious agents. Report any infection suspected to have been transmitted by this product to Pfizer Inc. at 1-800-438-1985. 

  • Infections: Monitor patients carefully for concurrent infection, including cytomegalovirus, Epstein-Barr virus, and herpes simplex virus infection.

  • Immunizations: Do not administer live vaccines to patients about to receive, receiving, or after treatment with ATGAM.
  • Thrombocytopenia and Neutropenia: If thrombocytopenia occurs, consider platelet transfusions to maintain platelets at clinically acceptable levels. Consider discontinuing ATGAM if severe and unremitting thrombocytopenia or neutropenia occurs.

Hepatic and Renal Function Tests: Monitor liver and renal functions as clinically indicated and manage according to relevant clinical guidelines. 
 

Adverse Reactions

The most clinically significant adverse reactions are anaphylaxis, infection, thrombocytopenia, leukopenia, arthralgia, edema, bradycardia, and abnormal renal and liver function tests.

Drug Interactions
A potential pharmacodynamic interaction concerns the concomitant administration of ATGAM with corticosteroids and other immunosuppressants, which are associated with an increased susceptibility to bacterial, viral, and fungal infections. The severity of the infections such as septicemia may be masked, and their clinical presentations may be atypical.

Monitor patients receiving ATGAM and immunosuppressive agents such as corticosteroids when the dose of corticosteroids and other immunosuppressants is being reduced, since this adjustment of dose may result in reduced immunosuppression and lead to development of previously masked reactions to ATGAM.

Use in Specific Populations

Pregnancy: Use only if the potential benefit to the mother justifies the potential risk.

Lactation: Discontinue breast-feeding during treatment with ATGAM or discontinue ATGAM treatment.

Contraception: Advise females of reproductive potential to use effective contraception during treatment with ATGAM and for at least 10 weeks after cessation of therapy. Advise males with a female partner of reproductive potential to use effective contraception during treatment with ATGAM and for at least 10 weeks after cessation of therapy.

Geriatric: Start dosing at the low end of the dosing range.

Please see full Prescribing Information, including BOXED WARNING.INDICATIONSATGAM is indicated for:
  • Management of allograft rejection in renal transplant patients; when administered with conventional therapy at the time of rejection ATGAM increases the frequency of resolution of the acute rejection episode.
  • Treatment of moderate to severe aplastic anemia in patients unsuitable for bone marrow transplantation.

LIMITATIONS OF USE

The usefulness of ATGAM has not been demonstrated in patients with aplastic anemia who are suitable candidates for bone marrow transplantation or in patients with aplastic anemia secondary to neoplastic disease, storage disease, myelofibrosis, Fanconi's syndrome, or in patients known to have been exposed to myelotoxic agents or radiation.Please see full Prescribing Information, including BOXED WARNING.