Please check your internet connection and try again.
**Drug:** Mylotarg (gemtuzumab ozogamicin)
## Overview
Gemtuzumab ozogamicin is a humanized antibody-drug conjugate that targets CD33, an antigen expressed on myeloid leukemia cells. It delivers a cytotoxic agent (calicheamicin) to the target cells.
## Primary Indications
Treatment of newly diagnosed acute myeloid leukemia (AML) in adult patients who are 75 years or older and are not candidates for intensive induction chemotherapy.
Treatment of relapsed or refractory AML in adult patients.
## Adult Dosing
**Newly Diagnosed AML (elderly, ineligible for intensive chemo):**
* Day 1: 3 mg/m² IV infusion over 2 hours.
* Day 4: 3 mg/m² IV infusion over 2 hours.
* Day 7: 2 mg/m² IV infusion over 2 hours.
* *Maximum dose per cycle: 6 mg/m²*
**Relapsed or Refractory AML:**
* Day 1: 3 mg/m² IV infusion over 2 hours.
* Day 4: 3 mg/m² IV infusion over 2 hours.
* Day 7: 2 mg/m² IV infusion over 2 hours.
* *Maximum dose per cycle: 6 mg/m²*
**Note:** A second course may be administered if AML has not progressed and the patient is in CR or CRp and has not experienced unacceptable toxicity. Dosing for the second course is 3 mg/m² IV infusion over 2 hours, without a dose escalation or scheduled daily doses.
## Pediatric Dosing
Not established.
## Dose Adjustments
* **Hepatotoxicity:** Hold gemtuzumab ozogamicin if bilirubin > 2 times the upper limit of normal (ULN) or AST/ALT > 2 times ULN (if bilirubin is within normal limits). Resume at a reduced dose (e.g., 1.5 mg/m²) upon resolution of hepatotoxicity, if clinically appropriate. If hepatotoxicity recurs, discontinue.
* **Mucositis:** Hold if Grade 3 or 4 mucositis. Resume at a reduced dose (e.g., 1.5 mg/m²) upon resolution to Grade 1 or less. If mucositis recurs, discontinue.
* **Thrombocytopenia:** Dose reductions are not specified due to the complexity of managing thrombocytopenia in AML patients and potential for bleeding. Closely monitor platelet counts.
## Contraindications
None.
## Adverse Effects
**Black Box Warnings:**
* **Hepatotoxicity:** Severe and potentially fatal liver toxicity, including sinusoidal obstruction syndrome (SOS)/veno-occlusive disease (VOD), has occurred. Risk factors include prior stem cell transplant, prior chemotherapy, and severe baseline liver disease.
* **Myelosuppression:** Severe thrombocytopenia, neutropenia, and anemia.
* **Infusion Reactions:** Symptoms include fever, chills, rash, or shortness of breath.
* **Embryo-Fetal Toxicity:** Can cause harm to a fetus.
**Common Adverse Effects:** Fever, nausea, vomiting, diarrhea, stomatitis, headache, rash, fatigue, cough, decreased appetite, abdominal pain, chills, and muscle pain.
## Key Drug Interactions
* **Anticoagulants/Antiplatelets:** Increased risk of bleeding. Monitor closely.
* **Other Chemotherapy Agents:** Potential for additive myelosuppression.
## Monitoring
* Complete blood counts (CBC) with differential and platelet counts regularly, especially during treatment and after discontinuation.
* Liver function tests (bilirubin, AST, ALT) before and during treatment.
* Signs and symptoms of infusion reactions.
* Signs and symptoms of SOS/VOD.
* Pregnancy status in women of childbearing potential.
## Clinical Pearls
* Administer prophylactic antiemetics due to high emetogenic potential.
* Premedication with corticosteroids, antihistamines, and antipyretics may be considered for infusion reactions, especially for the first dose.
* Ensure adequate hydration.
* Consider growth factor support as clinically indicated.
* Due to the risk of severe hepatotoxicity, patients with pre-existing liver impairment require careful monitoring.
***
*Disclaimer: This information is intended for healthcare professionals and does not replace a thorough review of the complete prescribing information, clinical guidelines, or individual patient assessment. Always verify current drug information with the manufacturer's official product insert and relevant medical literature before prescribing or dispensing.*
