In cancer treatment, a lower dose more often could keep tumors at bay

(Courtesy of Oregon St. U.)

Researchers at Oregon State University have changed up the dosing regimen for chemotherapy in an effort not to eliminate tumors but to control them via sustained delivery of the drug at lower amounts.

In common approaches to chemotherapy, doctors employ an all-or-nothing approach--they start a patient on the maximum tolerable dose of the drug to knock the cancer out quickly. But because these drugs are inherently harmful not only to tumors but to healthy cells as well, the patient will eventually need a break, during which the tumor could grow or become resistant.

The scientists in Portland, though, have created what they call a metronomic dosage regimen, in which they administer the chemotherapy at much lower doses but more often. Like containment booms surrounding an oil spill, the approach works to control the cancer’s spread and kill a little of it at a time by cutting off blood supply.

According to the article, published in the journal Chemistry of Materials, the team used the drugs paclitaxel and rapamycin, which are common in ovarian cancer treatment. The two chemotherapy agents at only a tenth to a third of the maximum dose and delivered via polymer nanoparticles into the tumor are able to act together to both attack the cancer and cull its growth.

Looking forward, they imagine the process will work best to treat complex cancers such as ovarian, sarcoma, breast, prostate and lung, all of which can be difficult to treat with the maximum tolerable dose.

“This new system takes some existing cancer therapy drugs for ovarian cancer, delivers both of them at the same time and allows them to work synergistically,” lead researcher Adam Alani said. “Imagine if we could manage cancer on a long-term basis as a chronic condition, like we now do high blood pressure or diabetes. This could be a huge leap forward.”