The European Commission, which oversees legislation and regulation for the European Union, has approved a therapy for pediatric patients with non-metastatic, resectable osteosarcoma, a type of bone cancer.
The approval is based on clinical studies led by researchers at The University of Texas M. D. Anderson Cancer Center and a national co-operative group.
MEPACT (mifamurtide, L-MTP-PE) is an immune-based therapy, that when combined with chemotherapy, resulted in approximately a 30 percent decrease in the risk of death with 78 percent of patients surviving more than six years following treatment. This therapy is the first in more than 20 years to improve the long-term survival of osteosarcoma patients.
Eugenie Kleinerman, M.D., head of the Children's Cancer Hospital at M. D. Anderson Cancer Center, was the first investigator to translate the drug from preclinical testing to a Phase I clinical trial in humans. She also led the Phase II clinical trial for pediatric patients with relapsed osteosarcoma, which was followed by a Children's Oncology Group Phase III trial for newly diagnosed patients.
Kleinerman originally proposed the use of this immune therapy for osteosarcoma after Isaiah J. Fidler, D.V.M., Ph.D., professor in M. D. Anderson's Department of Cancer Biology and director of the Center for Metastasis Research, demonstrated that MEPACT induced the regression of melanoma lung metastases in mice.
"When he showed that MEPACT caused the macrophages in the lung to kill tumor cells, I decided that the drug may have therapeutic potential in patients with osteosarcoma, which most often metastasizes to the lungs," says Kleinerman. "From my own preclinical research, we were able to show how MEPACT stimulated human immune cells to react against osteosarcoma cells."
MEPACT works by stimulating certain white blood cells, called macrophages, to kill tumor cells. The drug is shaped in a sphere, also known as a vesical, made up of lipids. Inside the vesical is muramyl tripeptide (MTP). The lipids trigger the macrophages to consume MEPACT. Once consumed, the MTP stimulates macrophages, particularly in the liver, spleen and lungs, to find tumor cells and kill them.