The FDA recently approved Voraxaze (glucarpidase) for the treatment of toxic methotrexate levels in the blood due to kidney failure.
Methotrexate levels are quickly lowered by glucarpidase, an enzyme that breaks down the chemotherapy drug to a form that can be eliminated from the body.
According to Richard Pazdur, MD, director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research, “Prolonged exposure to high levels of methotrexate can result in kidney and liver damage, severe mouth sores, damage to the lining of the intestine, skin rashes, and death due to low blood counts. Voraxaze is an important new treatment option for cancer patients aimed at preventing these toxicities associated with sustained high levels of methotrexate.”
To evaluate the effectiveness of glucarpidase, a single clinical study was performed involving 22 patients receiving the drug. Success within the study was achieved when patient methotrexate levels fell below a critical level within 15 minutes after administration and stayed below the critical level for 8 days. Of the 22 patients in the study, 10 met this standard. Although not all patients realized this result, glucarpidase eliminated 95% of the methotrexate in all study patients.
In the clinical study, the most common side effects recorded in more than 1% of patients were abnormal sensation, flushing, headache, low blood pressure, nausea, and vomiting.
Source: FDA.