anti-thymocyte and -lymphocyte globulin in aplastic anaemia

Last reviewed 01/2018

Anti-thymocyte globulin (ATG) and anti-lymphocyte globulin (ALC) have been shown to prolong survival in 40-70% of patients. They may be used singly or in conjunction with androgens, high dose corticosteroids or haplo-identical bone marrow cells.

The optimal source, dose and durations are undecided. Haematological recovery is slow and may require transfusion support. Blood counts usually remain unchanged for 1-3 months following commencement of therapy.

There are significant side effects in most patients including fever, chills, rashes (erythematous and urticarial), hypertension, and temporary worsening of thrombocytopenia. There may be anaphylaxis. Antihistamines may reduce the side effects. Serum sickness occurs 6-18 days after the start of therapy in 75% of patients and may be controlled by prednisolone. About 15% of patients relapse within 2 years of treatment but often respond to a second course.

Patients whom receive ATG within 6 months of diagnosis are more likely to respond than those with prolonged aplasia. There are no other predictive factors.