Normally reserved federal health officials are using phrases like "major turning point" and "lifesaving" treatment to describe a drug that cuts the risk of breast cancer recurrence by half in women with particularly aggressive tumors.
Herceptin, made by Genentech Inc., a WebMD sponsor, is already approved for the treatment of breast cancers that have recurred following surgery in women whose tumors overproduce a protein called HER-2. Between 20 percent and 30 percent of breast cancers are HER-2 positive.
But two new federally-run studies show that Herceptin is also remarkably effective for preventing recurrences in these high-risk women. The results were so impressive that the trials were halted two years early.
Herceptin is called a targeted therapy because it works by attacking a specific target -- the HER-2 protein. It's believed this stops the cancer cells from growing and/or stimulates the body's own immune system to attack the cancer cells.
'A Major Advance'
Women treated with Herceptin along with standard chemotherapy had a 52 percent reduction in breast cancer recurrence, compared with women treated with chemotherapy alone.
"This is a major advance for many thousands of women with breast cancer," National Cancer Institute Director Andrew C. von Eschenbach, MD, says in a news release. "These results are one more example that we are at a major turning point in the use of targeted therapies to eliminate suffering and death from cancer."
The NCI's JoAnne Zujewski, MD, who oversees breast cancer trials for the agency, says the findings prove the drug is "truly lifesaving."
"I have been in breast cancer for 12 years and this is the most remarkable result I have seen from a single intervention," she tells WebMD.
Oncologist Edith A. Perez, MD, who led one of the two research teams, tells WebMD that the findings should immediately change clinical practice for women with HER-2 positive cancers that have spread to the lymph nodes.
Most of the women in the two trials fell into this category. A few had breast cancer that had not spread, but it is not yet clear if the benefits of the treatment outweigh the risks for these women.
Paramount among those risks is a long-recognized link to heart damage. Standard chemotherapy for breast cancer leads to heart failure less than 1 percent of the time. But women who received chemotherapy plus Herceptin had a 3 percent to 4 percent increased risk of heart failure.
"This is a highly effective treatment, but it comes at a price," Zujewski says. "Women with HER-2 positive tumors that are also lymph-node positive should definitely talk to their doctors about getting on this drug. But we don't have the data yet to say that about women with lymph-node negative tumors."
About 211,000 women are diagnosed with breast cancer each year in the United States. Genentech officials estimate that up to 25 percent of these women could benefit from taking Herceptin following surgery.
The analysis that led to the halting of the two trials was based on results from 3,300 women enrolled in the two studies starting in 2000. Complete findings from the trials will be presented at the annual meeting of the American Society of Clinical Oncology in Orlando, Fla., next month.
Perez told WebMD that at the four-year follow-up, 85 percent of the women treated with Herceptin and chemotherapy were alive with no breast cancer recurrence, compared to 67 percent of women treated with chemotherapy alone.
University of Kentucky professor of oncology Edward Romond, MD, who led the second study, says Herceptin dramatically reduced the risk associated with HER-2 positive tumors.
"For women with this type of aggressive breast cancer, the addition of [Herceptin] to chemotherapy appeared to virtually reverse prognosis from unfavorable to good," he says in a news release.
That is the best news that study participant Darlene Nipper has had in a long time.
Nipper, who is now 40, was diagnosed with HER-2 positive breast cancer that had spread to the lymph nodes two years ago. She says she understood the seriousness of the diagnosis at the time and considered Herceptin her only hope.
"We really didn't know if it would have any effect at all, but I knew there really wasn't anything else out there for me," she says.
The Washington, D.C., consultant, who is a former executive director for Black Education Television, says that while there was great promise surrounding the targeted therapy, she didn't understand how effective Herceptin really was until federal officials made their announcement this week.
"I am just beginning to realize what an emotional roller coaster I have been on," she tells WebMD. "Even though I am a so-called survivor of breast cancer, there is always that thought in the back of your mind that the potential for recurrence is great."
More Excitement to Come
Nipper says the news has made her more hopeful about her future and the future of other breast cancer patients.
"The idea that you can identify a specific genetic marker and target it ... that sounds like something we used to read in sci-fi books," she says. "I don't think the public fully appreciates yet how incredible this is and how exciting it is for the future."
Zujewski agrees, adding that the Herceptin trials represent the turning of a corner in the development of targeted breast cancer treatments.
"I suspect that the next 10 years are going to be a lot more exciting than the last 10 years, and the last 10 years were pretty exciting," she says.
SOURCES: News release, National Institutes of Health. Andrew C. von Eschenbach, MD, director, National Cancer Institute. Edith A. Perez, MD, researcher and medical oncologist, Mayo Clinic, Jacksonville, Fla. Edward Romond, MD, professor of oncology, University of Kentucky, Lexington. JoAnne Zujewski, MD, NCI Cancer Therapy Evaluation Program. Darlene Nipper, breast cancer patient, participant in Herceptin trial. WebMD Medical Reference provided in collaboration with The Cleveland Clinic: "Breast Cancer: Herceptin."