Results of a phase I clinical trial showed that a new drug targeting mitochondrial function in human cancer cells was safe and showed some efficacy in a heavily pretreated cohort of patients. The findings were published in Clinical Cancer Research (2014; doi:10.1158/1078-0432.CCR-14-10190).
“This drug is selectively taken up by cancer cells and then shuts down the production of energy in the mitochondria,” said lead author and principal investigator Timothy Pardee, MD, PhD, director of leukemia translational research at the Comprehensive Cancer Center of Wake Forest Baptist University School of Medicine in Winston-Salem, North Carolina. “This is the first drug to inhibit mitochondria in this way and if it proves effective in further clinical trials, it will open up a whole new approach to fighting cancer.”
Mitochrondria, which are the powerhouses of a cell, are used differently by healthy cells and cancer cells. Healthy cells use mitochondria as a source of energy to carry out essential functions, whereas leukemia cells use it to reproduce faster and to repair damage from chemotherapy, Pardee said.
In the phase I trial, 26 patients with relapsed or refractory hematological malignancies were enrolled and given the new drug, CPI-613, as a 2-hour infusion on days 1 and 4 for 3 weeks every 28 days.
Of the 21 patients who completed the trial, 29% saw a benefit from the drug, including one who achieved a complete remission that has lasted more than 3 years and another who had a partial response that has lasted more than 2 years.
These data suggest that agents targeting mitochondrial metabolism can be safely administered and have activity in blood-related cancers such as leukemia, the researchers reported.
Based on these findings, a phase II clinical trial is underway at Wake Forest Baptist.