DrugindexOnline^{2nd edition}

Pronouncation: (an-tee-THIGH-moe-site GLAH-byoo-lin)
Class: Immune globulin

Trade Names:
Thymoglobulin
- Powder for injection 25 mg vials

Mechanism of Action

Pharmacology

Mechanism of action is not fully understood. Possible mechanisms include the following: T-cell Cl from the circulation and modulation of T-cell activation, homing, and cytotoxic activities.

Pharmacokinetics

Elimination

The t _½ is 2 to 3 days.

Indications and Usage

Treatment of acute allograft rejection in renal transplantation.

Contraindications

Acute viral illness; hypersensitivity to leporine proteins; previous hypersensitivity to anti-thymocyte globulin.

Dosage and Administration

Acute Renal Graft Rejection
Adults

IV 1.5 mg/kg/day for 7 to 14 days using a high-flow vein. Infuse over a minimum of 6 h for first infusion and over at least 4 h for subsequent doses.

Dosage Adjustment
Adults

IV Reduce 50% if the WBC is between 2,000 and 3,000 cells/mm ³ or if the platelet count is between 50,000 and 75,000 cells/mm ³ . Consider stopping treatment if the WBC falls below 2,000 cells/mm ³ or platelets below 50,000 cell/mm ³ .

General Advice

• Premedicate with corticosteroids, acetaminophen, and/or antihistamine 1 h before infusion of anti-thymocyte globulin as ordered.
• Allow vials to reach room temperature before reconstitution.
• Reconstitute each vial of powder for injection using 5 mL of supplied diluent (sterile water for injection) following manufacturer's guidelines. Do not shake vial during reconstitution. Gently rotate vial until powder is completely dissolved. Resulting solution provides 5 mg/mL of anti-thymocyte globulin.
• Transfer contents of appropriate number of reconstituted vials into bag of saline or dextrose infusion solution (recommended volume of 50 mL infusion solution per vial of anti-thymocyte globulin). Mix solution by gently inverting infusion bag once or twice.
• Do not administer if solution is discolored, cloudy, turbid, or if particulate matter is noted.
• Administer prescribed dose through a 0.22 micron filter into a high-flow vein.
• To reduce infusion-related adverse reactions (eg, fever, chills) infuse first dose over no less than 6 h and subsequent doses over no less than 4 h. Infusion rate may be further slowed if infusion-related reactions occur.

Storage/Stability

Store unopened vials in refrigerator (36° to 46°F). Protect from light and freezing. Use reconstituted vials within 4 h. Diluted infusion solution must be used immediately. Discard any unused solution. Do not save unused solution for future use.

Drug Interactions

Immunosuppressants (antineoplastic agents, corticosteroids, cyclosporines)

Risk of infection may increase.

Laboratory Test Interactions

May interfere with rabbit antibody-based immunoassays and with cross-match or panel-reactive antibody cytotoxicity assays.

Adverse Reactions

Cardiovascular

Hypertension (37%); tachycardia (27%).

CNS

Headache (40%); asthenia (27%); malaise (13%); dizziness (9%).

GI

Abdominal pain (38%); diarrhea, nausea (37%).

Hematologic-Lymphatic

Leukopenia (57%); thrombocytopenia (37%).

Hypersensitivity

Anaphylaxis.

Lab Tests

Hyperkalemia (27%).

Respiratory

Dyspnea (28%).

Miscellaneous

Fever (63%); chills (57%); pain (46%); infection (37%); peripheral edema (34%).

Precautions

Monitor Allergic reaction Monitor patient for signs of anaphylaxis or severe allergic reaction. Discontinue therapy and immediately notify health care provider if noted. Be prepared to treat appropriately. CBC Ensure CBC and differential are determined at baseline and periodically during course of therapy. Lymphocyte count Ensure lymphocyte count (total lymphocyte and/or T-cell subsets) is monitored during treatment to assess degree of T-cell depletion.

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Hypersensitivity

Anaphylaxis may occur.

Antibodies

Human anti-rabbit antibodies develop in 68% of patients.

Extravasation

Local irritation or phlebitis may occur. Refer to your institution specific protocol.

Prophylaxis

Ensure that potential value of antiviral, antibacterial, antiprotozoal, and/or antifungal prophylaxis has been evaluated.

Overdosage

Symptoms

Leukopenia, thrombocytopenia.

Patient Information

• Review the treatment regimen, including dosing schedule, duration of treatment, and monitoring that will be required.
• Advise patient, family, or caregiver that medication will be prepared and administered by health care provider in a health care setting.
• Advise patient, family, or caregiver that medication will be used in combination with other agents to achieve max benefit possible.
• Advise patient, family, or caregiver to immediately report any of the following to health care provider: rash; itching; hives; difficulty breathing; fever, chills, or other signs of infection; bleeding or unusual bruising; pain, redness, or swelling at injection site.