Antithymocyte Globulin (Rabbit) Monograph for Professionals

Brand name: Thymoglobulin Drug class: Immunosuppressive Agents - Antilymphocyte Immunoglobulins - Immunosuppressive Agents ATC class: L04AA04 VA class: IM600

Medically reviewed by Drugs.com on Jan 17, 2023. Written by ASHP.

Should be used only by clinicians experienced in immunosuppressive therapy for the management of renal transplant patients.

Antithymocyte globulin (rabbit) (ATG [rabbit]); rabbit-derived polyclonal antibody preparation; immunosuppressive agent.

Treatment of acute rejection of renal allografts in conjunction with other immunosuppressive agents.

ATG (rabbit) found to be more effective than ATG (equine) in reversing acute rejection episodes (88% compared with 76%) and preventing recurrent rejection episodes in renal transplant recipients.

Has also been used successfully as induction therapy in conjunction with maintenance immunosuppressive therapy for the prevention of renal allograft rejection† [off-label].

Induction therapy to prevent hepatic allograft rejection and minimize maintenance immunosuppression† [off-label] in pediatric patients (designated an orphan drug by FDA for this use) and in adults.

Has been used for the treatment of myelodysplastic syndrome† [off-label] (designated an orphan drug by FDA for this use).

Has been used for the treatment of aplastic anemia† [off-label], usually in conjunction with cyclosporine.

To reduce the incidence and intensity of infusion-related adverse effects, the manufacturer and some clinicians recommend premedication with corticosteroids, acetaminophen, and/or an antihistamine (e.g., diphenhydramine) 1 hour prior to each infusion. (See Infusion-related Effects under Cautions.)

The manufacturer recommends prophylactic antiviral therapy (e.g., acyclovir, ganciclovir, valganciclovir) during ATG (rabbit) therapy. (See Infectious Complications under Cautions.)

For drug compatibility information, see Compatibility under Stability.

ATG (rabbit) is administered by IV infusion. The manufacturer states that ATG (rabbit) should be infused through an inline 0.22-μm filter into a high-flow vein. Has also been administered via a peripheral vein† [off-label] in some patients, but safety not fully established and may increase risk of thrombophlebitis and DVT.

Administer in conjunction with other immunosuppressive agents.

Allow vial to reach room temperature before reconstituting. Reconstitute vial containing 25 mg of the drug with 5 mL of sterile water for injection to provide a solution containing 5 mg/mL. Gently rotate vial until powder is completely dissolved. Use reconstituted solution immediately. (See Storage under Stability.)

Dilute appropriate dosage of reconstituted ATG (rabbit) in 0.9% sodium chloride or 5% dextrose injection. Each reconstituted vial should be diluted in 50 mL of infusion solution; total volume of infusion solution required generally is 50–500 mL. Recommended final concentration approximately 0.5 mg/mL. Mix diluted solution by gently inverting infusion bag only once or twice.

Administer initial dose over ≥6 hours and subsequent doses over ≥4 hours. Slowing infusion rate may help prevent or ameliorate acute infusion reactions. (See Infusion-related Effects under Cautions.)

Appropriate dosage for Thymoglobulin differs from dosages for other antithymocyte globulin (ATG) preparations since protein composition and concentrations vary depending on source of ATG used. Exercise care to ensure prescribed dose is appropriate for the ATG preparation being administered.

Reduce ATG (rabbit) dosage by 50% if WBC is ≥2000 but ≤3000/mm3 or platelet count is ≥50,000 but ≤75,000/m3. Consider drug discontinuance if WBC