Gemtuzumab Ozogamicin

Brand Names: Mylotarg

Drug Class: CD33-directed Immunoconjugate

Overview

11 DESCRIPTION Gemtuzumab ozogamicin is an antibody-drug conjugate (ADC) composed of the CD33-directed monoclonal antibody (hP67.6; recombinant humanized immunoglobulin [Ig] G4, kappa antibody produced by mammalian cell culture in NS0 cells) that is covalently linked to the cytotoxic agent N-acetyl gamma calicheamicin. Gemtuzumab ozogamicin consists of conjugated and unconjugated gemtuzumab.

Mechanism of Action

12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Gemtuzumab ozogamicin is a CD33-directed antibody-drug conjugate (ADC). The antibody portion (hP67.6) recognizes human CD33 antigen. The small molecule, N-acetyl gamma calicheamicin, is a cytotoxic agent that is covalently attached to the antibody via a linker. Nonclinical data suggest that the anticancer activity of gemtuzumab ozogamicin is due to the binding of the ADC to CD33-expressing tumor cells, followed by internalization of the ADC-CD33 complex, and the intracellular release of N-acetyl gamma calicheamicin dimethyl hydrazide via hydrolytic cleavage of the linker. Activation of N-acetyl gamma calicheamicin dimethyl hydrazide induces double-strand DNA breaks, subsequently inducing cell cycle arrest and apoptotic cell death. 12.

Indications

  • 1 INDICATIONS AND USAGE MYLOTARG is a CD33-directed antibody and cytotoxic drug conjugate indicated for: • treatment of newly-diagnosed CD33-positive acute myeloid leukemia (AML) in adults and pediatric patients 1 month and older ( 1.1 ). • treatment of relapsed or refractory CD33-positive AML in adults and pediatric patients 2 years and older ( 1.2 ). 1.1 Newly-Diagnosed CD33-positive Acute Myeloid Leukemia (AML) MYLOTARG is indicated for the treatment of newly-diagnosed CD33-positive acute myeloid leukemia in adults and pediatric patients 1 month and older. 1.

Common Doses

  • 3 mg
  • 4.5 mg
  • 0.1 mg
  • 6 mg

Dosage

2 DOSAGE AND ADMINISTRATION • Newly-diagnosed, de novo AML (combination regimen) Adults : - Induction: 3 mg/m 2 (up to one 4.5 mg vial) on Days 1, 4, and 7 in combination with daunorubicin and cytarabine ( 2.2 ). - Consolidation: 3 mg/m 2 on Day 1 (up to one 4.5 mg vial) in combination with daunorubicin and cytarabine ( 2.2 ). Pediatric patients 1 month and older : - 3 mg/m 2 for patients with body surface area (BSA) 0.6 m 2 or greater ( 2.2 ). - 0.1 mg/kg for patients with BSA less than 0.6 m 2 ( 2.2 ). - See Full Prescribing Information for complete dosing information ( 2.2 ).

Black Box Warning

WARNING: HEPATOTOXICITY Hepatotoxicity, including severe or fatal hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), has been reported in association with the use of MYLOTARG as a single agent, and as part of a combination chemotherapy regimen. Monitor frequently for signs and symptoms of VOD after treatment with MYLOTARG. ( 5.1 and 6.1 ) WARNING: HEPATOTOXICITY See full prescribing information for complete boxed warning.

Contraindications

  • 4 CONTRAINDICATIONS MYLOTARG is contraindicated in patients with a history of hypersensitivity to the active substance in MYLOTARG or any of its components or to any of the excipients. Reactions have included anaphylaxis [see Warnings and Precautions (5.2) , Adverse Reactions (6) ] . Hypersensitivity to MYLOTARG or any of its components ( 4 ).

Side Effects

  • 6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: • Hepatotoxicity, including VOD [see Warnings and Precautions (5.1) ] • Infusion-related reactions [see Warnings and Precautions (5.2) ] • Hemorrhage [see Warnings and Precautions (5.3) ] The most common adverse reactions (greater than 15%) were hemorrhage, infection, fever, nausea, vomiting, constipation, headache, increased AST, increased ALT, rash, mucositis, febrile neutropenia, and decreased appetite ( 6 ). To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc.

Interactions

  • No major interactions listed on the FDA label. Always consult a healthcare professional.