Antithymocyte Immunoglobulin

What it is and how it works

Purified rabbit IgG directed against human thymocytes. It binds a wide range of T-cell surface antigens, causing T-lymphocyte depletion through complement-dependent lysis and opsonisation, and modulates residual T-cell function.

Indications

Prophylaxis and treatment of acute rejection in organ transplantation (including steroid-resistant rejection); prophylaxis of graft-versus-host disease in haematopoietic stem cell transplantation; aplastic anaemia.

Dosage and administration (summary)

Dosing is individualised by the transplant or haematology specialist according to indication and protocol; given by slow intravenous infusion into a high-flow vein, with premedication (corticosteroid, antihistamine, antipyretic).

Contraindications

Hypersensitivity to rabbit proteins or excipients; acute or chronic active infections that would contraindicate further immunosuppression.

Warnings and precautions

Infusion-associated reactions and cytokine release syndrome, including fever, chills, hypotension and rarely anaphylaxis, are common; resuscitation facilities must be available. Causes leucopenia and thrombocytopenia; monitor blood counts and adjust dose. Increased risk of infections (including CMV) and post-transplant lymphoproliferative disorder.

Pregnancy

Use only if clearly needed because data are lacking.

Storage and supply

Store at 2–8 °C refrigerated; do not freeze; protect from light.

Source: reference summary prepared from the EU SmPC/EPAR, BNF and WHO Model Formulary. The approved product information in Iran governs.