In previous investigations in which the body's immune system was marshaled, a personalized vaccine helped patients with ovarian cancer to defend against their tumors more than standard therapy and significantly improved their survival rates.
The vaccine was tested in a preliminary clinical trial and used with standard chemotherapy and a means to boost the immune system. Experimental therapy, recently described in the journal Science Translational Medicine, brings together a number of approaches that jointly drive innovation in cancer treatment.
Because the treatment uses the patient's immune cells as a kind of T-cell training session, it is an immunotherapy. Because it uses the distinctive proteins on a patient's own tumor as a reference beacon, it is a targeted therapy. And because a patient's cells are harvested and returned to them, it's a personalized therapy.
Instead of collecting a patient's T cells and redesigning them in a lab to find cancer, this treatment reaps a class of immune "helpers." Called dendritic cells. Using crushed cells from a patient's tumor, the researchers trained the dendritic cells to detect and attack this specific malignancy. When these enriched cells were returned to the patient, they gave their training to the army of killer T-cells of the immune system and sent them into the fight.
Among 10 women with advanced ovarian cancer, who received once every three injections of the personalized vaccine weeks – with the drugs cyclophosphamide and bevacizumab (marketed as Avastin) – eight showed a strong immune response and were still alive after two years.
In a comparison group of 56 patients who only received standard chemotherapy, only half lived the two-year mark.
Among a second cohort of 10 patients who received bevacizumab and dendritic cell vaccine alone (but no cyclophosphamide), only 30 percent survived until the two-year mark.
The main objective of the study was to test the safety of the vaccine in combination with the other drugs.
Among these study participants, as well as in subsequent cohorts of research topics, the vaccine was "so certain that it is unborn," said study leader Janos L. Tanyi, a gynecologist at the University of Pennsylvania, in the worst case, the subjects had brief seizures of Tiredness or flu-like symptoms, he said.
The same approach could also be helpful in fighting solid tumors in various organs, Tanyi said.
If ever a cancer is ripe for a more effective new treatment, it's Ovarian Cancer the fifth most common cause of death in the United States and the deadliest of all gynecological cancers According to the Centers for Disease Control and Prevention, it killed more than 14,000 American women in 2014.
Because there is no effective screening mechanism It is often discovered for ovarian cancer when it has reached an advanced stage Percentage of women diagnosed fail to remedy malignancy through a combination of surgery and chemotherapy, and it is repeated.
A personalized ovarian cancer vaccine is likely to be years away from widespread use. Scientists are likely to have to find a way to produce larger quantities of vaccine with a limited supply of tumor cells, Tanyi said. Meanwhile, researchers are already finding new ways to improve vaccine efficacy, he said.
As in other immunotherapy studies, Tanyi has found that some patients were able to stop the progression of the cancer with continued vaccination. In some women, the vaccine seems to have completely turned the cancer into remission.
Tanyi said he was curious to see if the dendritic cell vaccine could also be used as a first-line therapy in women with newly diagnosed ovarian cancer. To supply tumor cells for the vaccine, such patients would still have to be surgically removed.