Banned Rx May Save Young Lives

Children with leukemia had reduced relapse rates with gemtuzumab

(RxWiki News) A medication taken off the market in 2010 may have a new use in treating children with an aggressive form of blood cancer.

In a new study, children with acute myeloid leukemia (AML) treated with Mylotarg (gemtuzumab) and chemotherapy had less disease relapse compared to children who received only chemotherapy.

Findings from this new study support the results of recent research showing that adding gemtuzumab to standard chemotherapy had a similar impact in adults with AML.

"Track clinical research being conducted for your disease."

Alan Gamis, MD, MPH, associate oncology division director at Children's Mercy Hospital in Kansas City, led a team of researchers who evaluated treating children with acute myeloid leukemia with gemtuzumab.

AML starts in the bone marrow — the soft, spongy inner part of the bones. All blood cells are made in the bone marrow. And while AML starts in the bone marrow, it can quickly spread to the blood.

Gemtuzumab was approved by the US Food and Drug Administration (FDA) in 2000 to treat AML in patients 60 years and older whose disease did not respond to chemotherapy.

A 2004 post-approval trial showed gemtuzumab did not improve clinical benefits when combined with chemotherapy. Furthermore, more patients who had the combined therapy died than patients who received chemotherapy alone. As a result, the medication was withdrawn from the market in 2010.

For this study, Dr. Gamis and his team evaluated 1,022 children at trial sites throughout the US. The average age of participants was 10 years.

The children were randomly assigned to receive either gemtuzumab along with standard chemotherapy or chemotherapy alone.

"Chemotherapy has limits,” Dr. Gamis said in a statement. "Particularly in children, increasing doses further can become too toxic for the patient while still not achieving the desired effect on the cancer."

His team of researchers found that adding gemtuzumab to standard therapies extended the time during which there was no evidence of disease (disease-free survival).

After three years, disease-free survival for children who received the combined therapy was 61 percent, compared to 55 percent for the youngsters who received only chemotherapy.

The risk of relapse was also lower in the gemtuzumab-treated children — 33 percent versus 41 percent of the children who received the standard therapy.

Gemtuzumab did not significantly extend overall survival, however, with 74 percent of participants in the gemtuzumab group still alive after three years, compared to 70 percent of those who received traditional chemotherapy.

"This study is significant because it shows for the first time that this targeted treatment can augment the effects of chemotherapy in children and effectively reduce their risk of relapse. We found it was most effective in the patients most at risk,” Dr. Gamis said.

Results from this study were presented at the 55th American Society of Hematology meeting.

It should be noted that all research is considered preliminary before being published in a peer-reviewed journal.

Review Date: 
December 9, 2013