Rabbit antithymocyte globulin (rATG or Thymoglobulin) is the most common agent used in more than 55% of transplant cases in the USA, despite not being FDA-approved for this use (only for treatment of severe cellular rejection). Curiously, rATG is prepared by immunizing pathogen-free
rabbits with a cell suspension of human thymic tissue (thymocytes). After immunization, the serum is harvested from rabbits and immunoglobulins against thymocytes are isolated and subjected to a number of purification processes. Samples from more than 26,000 immunized rabbits are pooled to achieve a high level of batch-to-batch consistency!
Our center uses ATG for induction in high immunological risk patients and Basiliximab for low risk patients in combination with tacrolimus and MMF for maintenance. Steroid withdrawal is performed on most patients by the end of first week post-transplantation, with the exception of highly sensitized patients.
Below a summary table of the 3 most common induction agents in clinical use today, their target cells, dose, cost and side effects.
Antibody | Brand | Class | Lymphocyte depleting | Antigenic Target and Cells | Typical prescription | Side effects |
Basiliximab | Simulect (Novartis) | Monoclonal | No |
IL2 receptor (CD25) Activated T cells |
20mg x2 doses U$4,254 | Hypersensitivity reaction (rare) |
Rabbit antithymocyte globulin | Thymoglobulin (Genzyme) | Polyclonal | Yes |
Multiple Ag Mainly T cells, to a lesser extent B and NK cells |
1.5mg/kg 3-7 doses U$7,824-18,256 Premedicate with steroids and Tylenol Decrease dose if WBC<3 or="" ptls="" span=""> 3> |
Fever, chills, dyspnea, nausea, diarrhea, headache, general pain and pulmonary edema (cytokine release syndrome) |
Alemtuzumab | Campath 1H (Berlex Laboratories) | Monoclonal | Yes (more prolonged) |
CD52 Ag T, B and NK cells, monocytes, macrophages, dendritic cells, eosinophils, mast cells |
30mg x1 dose U$2,065 |
Generally none when given subcutaneously |
More details about the use of induction therapy in transplantation on this prior blog
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