CONTACT: Kristi Hellmuth
Johanna Spangenberg; (202) 638-7222
NEWS ROOM: March 20-26, 1997
Pointe Hilton on South Mountain
Phoenix, AZ
(602) 431-6501
HUMAN BRCA1 GENE THERAPY RESULTS RELEASED; OPTIMUM DOSE AND SCHEDULE FOR BRCA1 THERAPY IN WOMEN WITH METASTATIC OVARIAN CANCER DETERMINED
Preliminary Results from Study of 12 Ovarian Cancer Patients Offers Clues for New Gene Therapy Treatment
PHOENIX, AZ (March 26, 1997)-- Five years ago the first breast cancer susceptibility gene was identified, and was named BRCA1 (BReast CAncer gene 1). After intensive research, the responsible gene was further characterized in 1994 and as expected, appeared to function as a tumor suppresser (a factor that inhibits cellular growth). Overall, genetic alterations or mutations in BRCA1 may account for 5-10% of all cases of breast cancer and 50% of cases where there are other affected family members. Women who carry certain mutations in BRCA1 have approximately an 80-85% chance of developing breast cancer in their lifetime as well as about a 40-60% risk of ovarian cancer. Retroviral gene replacement therapy is now being studied as a form of treatment for women with ovarian cancer in an attempt to restore BRCA1's tumor suppressor function.
Medical researchers contend that tumors confined to the peritoneal cavity may represent the best targets for gene therapy. Researchers at Vanderbilt University and the University of Washington Medical Centers, set out to determine the dose and toxicity of BRCA1 retrovirus gene therapy in women with metastatic ovarian cancer. Twelve women with ovarian cancer were treated with intraperitoneal or "belly bath" retroviral BRCA1.
Authors of the study are gynecologic oncologist David L. Tait, MD, molecular biologist and pathologist, Jeffrey Holt, MD, both from Vanderbilt University Medical Center in Nashville, and geneticist Mary Claire-King, Ph.D., University of Washington, Seattle, WA.
The results of this research were presented at the 28th Annual Meeting of the Society of Gynecologic Oncologists, at the Pointe Hilton on South Mountain, Phoenix, AZ. In addition to gynecologic oncologists, the organization's 800 members include medical oncologists, radiation therapists, and pathologists whose primary professional commitment is to the treatment of women with gynecologic malignancies, including cancers of the ovary, endometrium, uterus, cervix, vagina, and vulva, as well as trophoblastic disease.
The Study
The patients were examined for toxicity of this treatment. Patients with recurrent or persistent metastatic ovarian cancer previously treated with standard surgery and chemotherapy and a measurable tumor confined to the peritoneal cavity were considered for this study. The 12 patients
selected were treated for four consecutive days with intraperitoneal BRCA1 gene therapy. Five dose levels were studied with an eye to future responses.
Research Results
The medical specialists examined patients' peritoneal fluid for the presence of stable BRCA1 retroviral vector 24 hours after virus administration. Antibodies, which destabilize the therapy, were rarely present. The toxicity was minimal, allowing better quality of life when compared to chemotherapy. Two patients showed a decreased tumor cell count; one patient had a reduction in the size of a radiographically measurable tumor.
The research team concluded that (1) antibody response to the retroviral vector is rare; (2) the retroviral vector is stable for at least 24 hours in the peritoneal cavity; and (3) toxicity was limited.
The presence of stable disease in some patients suggests there may be potential effectiveness of this treatment. This Phase I Trial research adds to the growing knowledge regarding the effectiveness and safety of BRCA1 gene therapy for ovarian cancer as well as other tumor sites.
According to David Tait, MD, an author of the study, "This is an early gene therapy trial in humans focusing on BRCA1, an important gene in breast and ovarian cancers. While therapeutic efficacy was not the focus of this study, our prior animal experiments have suggested a potential therapeutic effect for BRCA1 gene therapy. We have taken a first step towards a human study that shows promise."
The authors of this study are available to talk to the media regarding their study objectives, methodology, and results. Contact Kristi Hellmuth or Johanna Spangenberg at (202) 638-7222 for more information about this research or an interview with the authors.
RSS