CHAMPAIGN-URBANA, Ill. (WCIA) — A clinical trial of a cancer-treating drug at the University of Illinois is showing promise after its initial human trials, scientists and clinicians recently reported.
The drug – PAC-1 – spurs programmed cell death in cancer cells. It was first identified as a potential anti-cancer agent in the early 2000s when it was discovered that it could switch on a pathway that is suppressed in cancer cells. Scientists at the U of I were the ones to make that discovery.
Researchers reported that animal trials involving dogs with cancer found that an early formation of PAC-1 had anti-cancer effects. These animal trials, and a gift from an anonymous investor, set the stage for Phase I human trials, which started several years ago.
Dr. Arkadiusz Dudek, the Minnesota-based clinical director of the study, said Phase I trials are designed to test whether a new drug has worrisome side effects or toxicities in human patients; scientists can also look for early evidence of therapeutic benefits.
The trial enrolled cancer patients with advanced disease who had run out of other treatment options.
“We had patients with colon cancer, breast cancer, pancreatic cancer, adenocarcinoma, melanoma and others,” Dudek said.
Researchers found that that PAC-1 only had minor side effects in patients with end-stage cancer. It stalled the growth of tumors in five people with neuroendocrine cancers and reduced the tumor size of two of those patients. In addition, it showed some therapeutic activity against sarcomas.
More results from trials involving patients with glioblastoma multiforme are expected soon – this is an aggressive form of brain cancer that currently has only one drug available to treat it. Previous testing showed that PAC-1 does cross the blood-brain barrier, which is essential for any brain cancer treatment.
With Phase I trials complete, clinicians and researchers are looking for further funding to move the drug into Phase II trials, which would involve many more and much healthier patients.
“Our strategy is to figure out which tumor type will be the most sensitive and pursue that,” Dudek said. “So we are very excited about the results in neuroendocrine tumors because there are not many drugs available for that disease.”
If trials reveal that PAC-1 is therapeutic against one or more cancer types and if the drug is improved for use in those populations, researchers said it will make it less costly to test it against other cancers. An approved drug can also be prescribed for “off-label” use by doctors who think their patients might benefit from adding it to treatment protocols.
But researchers are still years away from even knowing the results of Phase II clinical trials. It will take even more time than that for PAC-1 being to be approved for cancer treatment.