An experimental drug from Nektar Therapeutics was able to shrink tumors and reduce a cancer biomarker in women with advanced ovarian cancer in a mid-stage study, the Sun-Sentinel reports. Twenty-three percent of patients who took NKTR-102 once every three weeks saw significant tumor shrinkage, and 38 percent saw a marked reduction in the ovarian cancer biomarker CA-125. About 48 percent of patients saw "sustained benefits" from the drug. NTKR-102, formulated to provide a continuous concentration of the cancer drug irinotecan, is also being tested on patients with metastatic breast cancer and colorectal cancer. The newspaper reports that nearly 70 percent of women with advanced cancer die within five years. According to the U.S. Centers for Disease Control, ovarian cancer is the eighth most common cancer among women. The disease kills more women than any other cancer of the female reproductive system. Earlier this month, Roche announced that its cancer drug, Avastin, when used in combination with chemotherapy, helped ovarian cancer patients in a late-stage study live longer without the disease progressing. Avastin is already used to treat a variety of cancers and is predicted to become the world's top-selling prescription drug. Other companies working in this space: U.K.-based Pharminox is developing Phortress, a DNA-interactive ovarian cancer drug formulated to induce apoptosis (cell death) in tumor cells. Preclinical studies have shown the drug to be effective against types of ovarian, breast, renal and lung cancer cells. Voreloxin, currently in development by Sunesis Pharmaceuticals, also works to induce apoptosis in cancer cells. Aduro Biotech has a pipeline of therapeutic immunotherapy vaccines based on its two Listeria monocytogenes platforms. The company recently announced encouraging results from a Phase I safety trial of CRS-207, its therapeutic vaccine for a variety of cancers. Endocyte is developing an ovarian cancer treatment using its "drug guidance" technology for the targeted delivery of therapeutics to diseased cells. Endocyte is currently testing EC-145, its drug candidate for non-small cell lung cancer and ovarian cancer.