OVARIAN CANCER Test drug prolongs patients' remission
Women with ovarian cancer can usually expect a two-year remission.
By LINDA MARSA
SPECIAL TO LOS ANGELES TIMES
Ovarian cancer is usually detected at an advanced stage and, as such, is one of the deadliest and most difficult cancers to treat. Therapy can eradicate the tumors, but most patients relapse within two years.
That time before relapse could eventually be extended. In a recent study, an experimental treatment was able to prolong remission significantly, offering hope to women who have exhausted conventional treatments.
"It's very exciting because we desperately need more good drugs to treat this deadly disease," says Dr. Jonathan S. Berek, a gynecological oncologist at University of California, Los Angeles' Jonsson Comprehensive Cancer Center who conducted a recent study of the therapy.
Normally, when a woman is diagnosed with ovarian cancer, she undergoes surgery to have the tumors removed. The ovaries, Fallopian tubes, uterus and parts of the bowel are often removed as well. Chemotherapy follows the surgery, and about 90 percent of patients then go into remission, a period of "watchful waiting."
"The problem is that over the next five to 10 years, as many as 90 percent of women will relapse and die," says Berek.
When the cancer returns, in other surrounding tissue, the cancer is more virulent and resistant to chemotherapy. But the new drug, OvaRex, works by "training the immune cells to ferret out the tumor cells and recognize them as foreign," says Dr. Christopher F. Nicodemus, a scientist at the company that makes OvaRex, Unither Pharmaceuticals in Wellesley Hills, Mass.
Normally, because tumors come from the same tissue as normal cells, the immune system doesn't recognize malignant cells as dangerous. However, ovarian cancer has an abnormal surface protein, or antigen, called the CA-125. The OvaRex antibody is programmed to latch onto this CA-125 protein, prompting an attack on cells with the markers.
In a test of 145 women with advanced cancer who had responded well to standard treatment, 73 received OvaRex, and the remainder received a placebo, or dummy pill. The women in the treatment group relapsed in an average of 24 months, vs. almost 11 months in the placebo group. Patients also didn't experience any of the harsh side effects associated with chemotherapy, according to the study, which was presented this month at a meeting of the American Society of Clinical Oncology in Chicago.