Researchers were surprised that late stage ovarian cancer patients responded well to an experimental carboplatin-decitabine combination therapy, given that they had become resistant to carboplatin. Indiana University researchers are eager to conduct a larger human study to test the two-drug combination with existing treatment for ovarian cancer.

The carboplatin-decitabine combo had a positive effect on 70% of the trial participants. The researchers added that they believe they have discovered biomarkers which could help better identify patients who are most likely to respond to this therapy.

Kenneth Nephew, cancer researcher in the IU Medical Sciences Program-Bloomington and at the Indiana University Melvin and Bren Simon Cancer Center, said:

"The potential that this regimen is efficacious, combining decitabine with the carboplatin therapy, is very exciting. It's well tolerated and didn't have any dose-limiting toxicities. We could enroll patients with confidence because of these results."

Ovarian cancer is the fifth largest cause of cancer death among females in the USA, the researchers explained. They added that it is an aggressive and incurable cancer. Although carboplatin is seen as the most efficient drug treatment, patients with recurring ovarian cancer frequently become resistant to the medication after a couple of treatment rounds. When resistance builds, they typically do not survive for more than one year because there aren't any effective second-line treatments around.

All the 17 women involved in the clinical trial were resistant to carboplatin, and their cancer was advancing. 12 of them saw their tumor growth either slow down significantly, or stop altogether after treatment with the experimental combo. In fact, Nephew said the tumor became undetectable in one of the women. He added that cancer progression resumed after about 336 days.

Lead investigator Daniela Matei, M.D., who has been treating ovarian cancer patients for ten years and has performed several human studies, was surprised by the high rate of positive effects. The number of women who remained in remission for at least six months was surprising, she added.

Matei said:

"Typically in this group of patients you'd anticipate response rates of less than 5 percent and no patients would be expected to be in remission at six months," said Matei, a physician-scientist at the IU Simon Cancer Center. "In our trial, more than half (nine women) of the patients were without progression at six months."

This research has been funded by the NIH (National Institutes of Health), National cancer Institute, Walther Cancer Foundation, and the Ovarian Cancer Research Foundation.

It is estimated that approximately 200,000 women are diagnosed with ovarian cancer each year globally, and 125,000 females die from the disease. About 22,000 new diagnoses of ovarian cancer are made each year in the USA, where about 15,500 die from it. Unfortunately, there is no really effective means of detecting the cancer early on.

Written by Christian Nordqvist