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HomeEfficacyEfficacyAplastic AnemiaRenal Allograft RejectionSafetyDosing & Administration
Prescribing Information, including BOXED WARNINGIndications
Aplastic Anemia EfficacyAplastic Anemia EfficacyIn the studies described below, the effectiveness of the ATGAM therapy was evaluated by the hematologic response and survival rates.1In the studies described below, the effectiveness of the ATGAM therapy was evaluated by the hematologic response and survival rates.1

ATGAM vs placebo1

ATGAM vs placebo1

Patients treated with ATGAM had greater hematological response than with placebo.

†32 patients in both the ATGAM group and the control group who crossed over to receive ATGAM.

Study 1 design

41 patients (6 to 69 years of age) with moderate or severe aplastic anemia who were not candidates for bone marrow transplantation were enrolled in this randomized controlled study. The treatment group (n=21) received ATGAM (20 mg/kg/day) for 8 days, while control patients (n=20) were observed for 3 months. All patients were given oral prednisone (40 mg/m2/day) starting on day 8 then tapered over 1 to 2 weeks. At 3 months post-enrollment, 11 patients in the supportive care group who showed no improvement became eligible and were crossed over to receive ATGAM therapy. Efficacy was evaluated as sustained improvement in peripheral blood counts within 3 months of entry into the study.1

ATGAM + androgen + bone marrow infusion vs ATGAM + androgen1

ATGAM + androgen + bone marrow infusion vs ATGAM + androgen1

Hematological response rate at 3 months and survival rate at 1 year for both treatment arms were comparable.

Response rate at 3 months

Survival rate at 12 months

Study 2 design

A randomized, double-blind, placebo prospective, controlled study compared ATGAM and androgen (oxymetholone; OXY) immunosuppressive therapy with the combination of ATGAM, androgen (OXY) and an infusion of human leukocyte antigen (HLA) mismatched bone marrow in 42 patients (1 to 69 years of age) with severe aplastic anemia who were not candidates for bone marrow transplantation. Allocation to treatment group was based on the availability of mismatched bone marrow donors. Eighteen patients received ATGAM (16 mg/kg/day for 10 doses) with concomitant androgens (OXY, 3 mg/kg/day) for a minimum of 3 months, and 24 patients received an infusion of bone marrow from an HLA-mismatched donor 48 hours after completion of ATGAM treatment.1

ATGAM + androgen vs ATGAM + placebo1ATGAM + androgen vs ATGAM + placebo1

The difference in response rates at 6 months and survival at 2 years was not significant in all 3 treatment arms.

Response rate at 6 months

Survival rate at 2 years

Study 3 design

Study 3 was a randomized, placebo-controlled, double-blind study of 53 patients (3 to 76 years of age) with moderate to severe aplastic anemia. All patients were treated with ATGAM (20 mg/kg/day IV) for 8 days and were randomized to receive the oral androgen (oxymetholone 4 mg/kg/day or fluoxymesterone 25 mg/m2/day) (n=26), or a matched placebo (n=27). Both groups received oral prednisone (40 mg/m2/day) beginning on day 8 which was tapered and discontinued in 1 to 2 weeks. Historical controls from previous studies (n=68; 1 to 72 years of age) who received ATGAM (20 mg/kg/day IV for 8 days) without androgens were included for treatment results comparison.1

Reference:ATGAM [prescribing information]. New York, NY: Pfizer Inc., May 2023.ATGAM Efficacy Explore ATGAM Safety Safety Loading Learn About ATGAM Dosing & Administration Dosing & Administration Loading ATGAM Ordering and Availability Information View Ordering and Availability InformationLoading

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PP-ATG-USA-0032
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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.