FDA re-approves Mylotarg® antibody-drug conjugate seven years after it had been withdrawn from the market

| Eric Furman, Ph.D.

Seven years after Mylotarg® (gemtuzumab ozogamicin) was voluntarily withdrawn from the market, the U.S. Food and Drug Administration has re-approved Mylotarg® product.

Mylotarg® product was first approved by the FDA in 2000 for the treatment of adults with CD33-positive acute myeloid leukemia (AML) who had experienced relapse. However, Mylotarg® product was voluntarily withdrawn from the market in 2010 after a postmarketing trial showed an increased risk of death in a subpopulation treated with Mylotarg® product in combination with chemotherapy.

The new FDA approval is for a lower recommended dosage range and a different administration schedule than the previous approval, and includes uses alone or in combination with chemotherapy. Additionally, the new FDA approval is for a different patient population than before, including adults with newly diagnosed CD33-positive AML, as well as certain younger patients who had experienced a relapse or had not responded to initial treatment.

Mylotarg® product is an antibody-drug conjugate that includes a humanized antibody against the CD33 antigen (a.k.a. Siglec-3, a marker of cells of the myeloid lineage) conjugated to a calicheamicin toxin.

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