Although it is rare, ovarian cancer tends to recur and to be very difficult to handle. Faced with this evil woman, therapeutic vaccination is a groundbreaking approach brings high hopes.
Is ovarian cancer relapse formidable vaccine contra les recidivist ovaries cancer?
The ovarian cancer is rare: there are about 4 500 new cases diagnosed each year in France, but in the same 3500 women die. The mortality rates approaching 75% in fact the most serious of gynecological cancers. He represents the 5th cause of cancer death in women. The average age of onset is 60 years with a peak incidence between 75 and 79 years, but it can reach younger women or girls.
5 to 10% of cases are genetic in origin, found in families with a gene predisposing Mutated BRCA1 or BRCA2. Despite effective treatment, a screening often delayed due to the discretion of symptoms, largely explains the very poor prognosis of this cancer. The treatment is both surgeries, in order to completely remove the tumor, chemotherapy, associating carboplatin and paclitaxel infusion of 6 courses.
Despite the excellent results of this first line therapy, the problem remains high recurrence rate. Women who suffer from cancer at late stage are put into complete remission in 80% of cases but 75% of them relapse after an average 16 to 18 months. “Treatment of relapse has progressed,” says Professor Pujade-Lauraine, chief of medical oncology at the Hotel-Dieu. “However, the median survival does not exceed 3 to 4 years, which is particularly disappointing, especially compared with the percentage of patients in remission initially” he added. “The challenge today is to develop a treatment subsequent to first-line treatment, may prevent relapse” said Professor Jacques Dauplat, chief of surgical oncology center Jean Perrin1.
An original therapeutic approach: immunotherapy
All tests for years with conventional treatments are improving the rate of relapse, ended in failure. A totally new approach to treatment is a therapeutic vaccine that would prevent recurrence after initial successful treatment. The principle of this approach immunotherapeutic based on injection of a molecule called Abagovomab patients suffering from ovarian cancer. The vaccine stimulates the immune system of women so that it selects and destroys tumor cells to prevent tumor recurrence. Focus on principle rather conventional Vaccine:
* This molecule is an antigen designed to resemble the CA125 antigen, a protein found in large quantities on the surface of tumor cells in ovarian cancer. The Abagovomab is nevertheless sufficiently different from the CA125 in order to induce, once injected, the immune response of the patient against him, and thereby against the CA125 antigen, very close.
* A classic immune response occurs when: the antibodies induced by the patient specifically recognize antigens CA125 in the tumor cells and bind to leading, ideally elimination of tumor cells carrying the antigen, now recognized as foreign. If the system works in practice is therefore the patient herself who synthesizes antibodies eradicating the tumor. Thanks to the vaccine based Abagovomab, the immune system should be able to recognize and attack tumor cells that have the protein CA125.
This could bring hope that the immune system starts to fight all residual tumor cells and that they succeed and to prevent any recurrence of the disease. “The medical community has great hopes on the immunotherapy. She hopes treatment that will prevent recurrence often fatal cancer of the ovary, “said Professor Pujade-Lauraine.
Ovarian cancer: an international study on a vaccine
Driving in 9 countries, the clinical MIMOSA2 testing the effectiveness of the vaccine based Abagovomab.
Launched in 2006 by Menarini pharmaceutical group, this trial represents the first phase III study of this size, to test the Abagovomab in consolidation therapy in women with ovarian cancer and who responded completely the first-line chemotherapy. The goal is to answer this question; does this vaccine capable of preventing the recurrence of high risk patients? Beyond this, the criteria are also studied overall survival, safety, treatment and duration of the immune response. France has since the end of 2008 among the countries involved.
The first results are expected in early 2011 and the final conclusions will be known in 2015. If Abagovomab meets these expectations, patients may fully benefit from the advanced first-line treatment in this disease and see their hopes of survival increased significantly in years to come.