Once removed from the market, the monoclonal antibody gemtuzumab ozogamicin (Mylotarg) is making a comeback with a new FDA (AML), the agency announced.
It was also okayed for treating patients ages 2 and up with CD33-positive AML who've had a relapse or are refractory to initial therapy.
The drug, made by Pfizer, will come with a boxed warning about severe or fatal liver damage, including blockage of veins in the liver.
Gemtuzumab was originally approved in 2000 for treating adult AML under the FDA's accelerated approval process, which required a follow-up trial to confirm that the drug had clinical benefits. But that trial didn't show better survival compared with standard chemotherapy, and the agent was associated with life-threatening veno-occlusive disease and other toxicities.
It was subsequently pulled from the U.S. market in 2010 by Pfizer at the FDA's request.
FDA said this approval comes with a lower recommended dose of the drug, a different schedule in combination with chemotherapy or on its own, and a new patient population.
"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," Richard Pazdur, MD, acting director of the FDA's hematology and oncology products division, said in a statement.
Approval follows positive results from a chemotherapy combination trial and two stand-alone treatment trials. In the chemo combo study of 271 patients with the condition, those who received gemtuzumab in their combinations had greater event-free survival than those without (17.3 months versus 9.5 months).
In the first stand-alone treatment trial of 237 patients, those newly diagnosed with AML who got the drug had greater overall survival than those on best supportive care (4.9 months versus 3.6 months), and in the second trial of 57 patients who'd had a relapse, 26% had complete remission that lasted a median of 11.6 months.
Common side effects of the drug included fever, nausea, infection, vomiting, bleeding, thrombocytopenia, stomatitis, constipation, rash, headache, elevated liver function tests, and neutropenia. Severe side effects included low blood counts, infections, liver damage, hepatic veno-occlusive disease, infusion-related reactions, and hemorrhage.
FDA had granted gemtuzumab orphan drug designation. In July, an advisory committee to the agency voted that the trials demonstrated a favorable risk/benefit profile for patients with the disease.