If a new treatment currently being tested at the University’s Comprehensive Cancer Center proves effective, breast cancer patients’ chances of relapsing could be greatly decreased.

Anne Schott, associate professor of internal medicine at the University Medical School, is leading a clinical trial on the effects of combining standard chemotherapy with a drug called Reparixin to destroy the stem cells in patients suffering from metastatic, or advanced stage, breast cancer.

Reparixin was originally designed and marketed by Dompé, a pharmaceutical company, to help transplant patients accept their new organs.

The idea for the research was first brought up by Dr. Max Wicha, director of the University Comprehensive Cancer Center, who realized that Reparixin could hit the drug target CXCR1 for breast cancer stem cells that he had been studying.

“In the laboratory it looked promising, so now we’re testing it in people,” Schott said. “This is the first time it’s ever been tested with chemotherapy and definitely the first time it’s ever been tested in cancer patients.”

She said stem cells are only a tiny part of a breast cancer tumor — anywhere from around 0.5 to five percent — yet they are responsible for creating new tumors and thus making it possible for women to relapse years after being initially treated.

While standard chemotherapy has proven effective in destroying most cancer cells, it does not target the stem cells. By combining the stem-cell targeted drug Reparixin with chemotherapy, Schott said she hopes to achieve not only the initial treatment but also prevent regrowth.

“We know that we have a combination therapy (that) can shrink tumors but the stem cell part — the part that can make tumor after tumor after tumor — those are resistant to chemotherapy,” she said. “What we’re developing is a combination treatment to try and do both: try to shrink the tumor but then also get rid of these stem cells that keep causing relapses.”

While the clinical trial is in its early phases, a number of women have shown interest in participating. At least one patient has been undergoing the combination treatment for a year, which Schott said is a promising sign as they are now able to determine that Reparixin reacts safely with standard chemotherapy.

The initial stages of the clinical trial were carried out to determine the best dose at which to administer Reparixin, but Schott said they’re able to move into a second and more comprehensive phase in which the researchers will try to determine the drug’s impact on the tumor’s stem cells.

“We’ve certainly seen responses in this treatment but we have to be careful interpreting that because of course the patients are receiving standard chemotherapy along with an experimental drug,” she said. “I wouldn’t want to overstate and say that we know right now that this is an effective treatment but certainly we’ve seen that it’s very possible to combine it with chemotherapy.”

The full scope and application of Reparixin is not yet known, and Schott said that until researchers do laboratory tests on the drug’s reaction with other forms of cancer, it’s not understood if this treatment can be applied more broadly.

“Obviously if it looks interesting in breast cancer, I think there will be a lot of research being done in other cancers to see if it might effective there, but we’re really starting with breast cancer at this point,” she said.

For now, the research will focus on breast cancer. In order for the Reparixin-chemotherapy combination to be approved as an official treatment, an additional clinical trial would be needed which would compare one subject pool using only chemotherapy to another using the combination.

All patients currently participating in Schott’s study are being given both drugs.

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