Please check your internet connection and try again.
# Mylotarg (gemtuzumab ozogamicin)
## Overview
Mylotarg is an antibody-drug conjugate that targets CD33, a protein found on the surface of myeloid leukemia cells. Upon binding, it is internalized, releasing the cytotoxic agent calicheamicin, which induces DNA damage and cell death.
## Primary Indications
* Acute Myeloid Leukemia (AML): Treatment of newly diagnosed CD33-positive AML in adults.
* Relapsed or Refractory AML: Treatment of relapsed or refractory CD33-positive AML in adults.
## Adult Dosing
**Newly Diagnosed CD33-Positive AML:**
* **First cycle:** 3 mg/m² on days 1, 4, and 7.
* **Second cycle (if residual disease present):** 3 mg/m² on days 1, 4, and 7.
* **Maximum cumulative dose:** 9 mg/m².
**Relapsed or Refractory CD33-Positive AML:**
* **First cycle:** 3 mg/m² on day 1.
* **Second cycle (if tolerated):** 3 mg/m² on day 1.
* **Maximum cumulative dose:** 6 mg/m².
*Note: Dosing may vary based on specific institutional protocols and patient tolerance.*
## Pediatric Dosing
The safety and efficacy of Mylotarg have not been established in pediatric patients.
## Dose Adjustments
* **Hepatotoxicity:** Discontinue treatment if AST/ALT > 3x ULN or bilirubin > 2x ULN. If LFTs normalize, consider restarting at a reduced dose (2.4 mg/m²) and a lower maximum cumulative dose.
* **Thrombocytopenia:** Dose reduction may be considered in cases of severe thrombocytopenia.
## Contraindications
* Known hypersensitivity to gemtuzumab ozogamicin or any component of the formulation.
* Active infrahepatic venous obstruction (e.g., Budd-Chiari syndrome).
## Adverse Effects
* **Hepatotoxicity:** Veno-occlusive disease (VOD)/sinusoidal obstruction syndrome (SOS) is a serious risk, characterized by jaundice, hepatomegaly, ascites, and thrombocytopenia.
* **Myelosuppression:** Anemia, neutropenia, thrombocytopenia.
* **Infusion-related reactions:** Fever, chills, rash, dyspnea.
* Nausea, vomiting, diarrhea, mucositis, fatigue, headache, hemorrhage.
## Key Drug Interactions
* **Hepatotoxic agents:** Increased risk of hepatotoxicity when used with other medications known to cause liver injury. Careful monitoring of liver function is essential.
## Monitoring
* **Liver function tests (LFTs):** Baseline and regular monitoring for AST, ALT, bilirubin, and alkaline phosphatase.
* **Complete blood count (CBC) with differential and platelet count:** Baseline and regular monitoring for myelosuppression.
* **Signs and symptoms of VOD/SOS:** Monitor for jaundice, edema, ascites, abdominal pain, hepatomegaly, and changes in coagulation parameters.
* **Infusion-related reactions:** Monitor vital signs during and after infusion.
## Clinical Pearls
* VOD/SOS is a serious and potentially fatal adverse event. Early recognition and prompt management are critical.
* Administer Mylotarg via a dedicated infusion line to prevent contamination with other medications.
* Consider prophylactic treatments for nausea and vomiting.
* Premedication with corticosteroids and antihistamines may be used to mitigate infusion-related reactions, though this is not universally established and depends on institutional protocols.
***
**Disclaimer:** This information is intended for healthcare professionals. Always consult the official prescribing information and relevant clinical guidelines for the most current and comprehensive drug details before making any treatment decisions.
