Thymoglobulin

Thymoglobulin is an immunoglobulin G indicated for the prophylaxis and treatment of acute rejection in patients receiving a kidney transplant. Use in conjunction with concomitant immunosuppression.

The first dose should be infused over at least 6 hours; doses on subsequent days should be infused over at least 4 hours.
Premedication with corticosteroids, acetaminophen, and/or an antihistamine prior to each infusion is recommended.
The Anti-Thymocyte Globulin dose should be reduced by one half if the white blood cell (WBC) count is between 2,000 and 3,000 cells/mm3 or if the platelet count is between 50,000 and 75,000 cells/mm3. Stopping Anti-Thymocyte Globulin treatment should be considered if the WBC count falls below 2,000 cells/mm3 or if the platelet count falls below 50,000 cells/mm3
Prophylaxis of acute rejection
: 1.5 mg/kg of body weight administered daily for 4 to 7 days
Treatment of acute rejection
: 1.5 mg/kg of body weight administered daily for 7 to 14 days

The most common adverse reactions and laboratory abnormalities (incidence>5% higher than comparator) are urinary tract infection, abdominal pain, hypertension, nausea, shortness of breath, fever, headache, anxiety, chills, increased potassium levels in the blood, low counts of platelets and white blood cells

Thymoglobulin should only be used by physicians experienced in immunosuppressant therapy in transplantation.
Immune-mediated reactions
: Thymoglobulin infusion could result in an anaphylactic reaction.
Infusion-associated reactions
: Close compliance with the recommended infusion time may reduce the incidence and severity of infusion-associated reactions.
Hematologic effects
: low counts of platelets and white blood cells have been identified and are reversible following dose adjustments. Monitor total white blood cell and platelet counts.
Infection
: Infections and reactivation of infections have been reported. Monitor patients and administer anti-infective prophylaxis.
Malignancy
: Incidence of malignancies may increase.
Immunization with attenuated live vaccines is not recommended for patients who have recently received THYMOGLOBULIN. THYMOGLOBULIN may interfere with rabbit antibody–based immunoassays and with cross-match or panel-reactive antibody cytotoxicity assays.

The mechanism of action by which polyclonal antilymphocyte preparations suppress immune responses is not fully understood. Possible mechanisms by which Anti-Thymocyte Globulin may induce immunosuppression in vivo include: T-cell clearance from the circulation and modulation of T-cell activation, homing, and cytotoxic activities. Anti-Thymocyte Globulin includes antibodies against T-cell markers such as CD2, CD3, CD4, CD8, CD11a, CD18, CD25, CD44, CD45, HLA-DR, HLA Class I heavy chains, and ß2 micro-globulin. In vitro, Anti-Thymocyte Globulin (concentrations >0.1 mg/mL) mediates T-cell suppressive effects via inhibition of proliferative responses to several mitogens. In patients, T-cell depletion is usually observed within a day after initiating Anti-Thymocyte Globulin therapy. Anti-Thymocyte Globulin has not been shown to be effective for treating antibody-mediated (humoral) rejections.