The United States Food and Drug Administration announced, this week, the approval of Pfizer Inc’s new acute meyloid leukemia treatmetn, Mylotarg (gentuzumab ozagamicin).
Now, this medicine will not treat all patients; it is mostly effective on newly diagnosed AML who also have tumors that express the CD33 antigen, and could also treat patients—ages 2 and older—who have relapsed CD33+ AML or did not respond a different initial treatment.
The drug had actually received accelerated FDA approval back in 2000 as a potential standalone treatment for older, relapsed CD33+ AML patients. Ten years later, however, the drug was voluntarily withdrawn—via FDA request—when later confirmatory trials did not verify any clinical benefit while demonstrating potential safety issues. Particularly, there was great concern over a potential elevation of early death risk.
Fortunately for Pfizer, though, more clinical trials have taken place since then and shown there is some benefit.
FDA Oncology Center of Excellence director, Richard Pazdur, MD, comments, ”
“We are approving Mylotarg after a careful review of the new dosing regimen, which has shown that the benefits of this treatment outweigh the risk. Mylotarg’s history underscores the importance of examining alternative dosing, scheduling, and administration of therapies for patients with cancer, especially in those who may be most vulnerable to the side effects of treatment.”
Also the acting director of the FDA Center for Drug Evaluation and Research Office of Hematology and Oncology Products, Pazdur assures that the FDA approval comes only after “a careful review of the new dosing regimen, which has shown that the benefits of this treatment outweigh the risk.”
AML is a form of rapidly-progressing cancer in the bone marrow which results in a higher than usual white blood cell count in the bloodstream. According to the National Cancer Institute and the National Institutes of Health, we will see an estimated 21,380 cases diagnoses this year; and nearly half as many deaths.
The most common side effects of this drug include fever, vomiting, nausea, infection, and bleeding. This medication can also result in low blood platelets, swelling in the mouth and mouth sores, constipation, rash, and headache. Severe side effects can include liver damage, infusion-related infections, severe bleeding, and hepatic veno-occlusive disease. Also, women who are pregnant or breastfeeding should be wary that the drug could harm a developing fetus or newborn baby.