The Food and Drug Administration (FDA) approved Perjeta for women with a form of early-stage breast cancer who face a high risk of having their cancer spread to other parts of the body.
Surgery to remove tumors is usually the first step in treating most forms of cancer. Perjeta is the first drug to be approved as a pre-surgical step.
"We are seeing a significant shift in the treatment paradigm for early stage breast cancer," Dr. Richard Pazdur, director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research, said in a statement. "By making effective therapies available to high-risk patients in the earliest disease setting, we may delay or prevent cancer recurrences."
Doctors hope that using cancer drugs earlier could help shrink tumors, making them easier to remove. In some cases, that could allow women to keep their breasts, rather than having a full mastectomy. Doctors also say that treating the disease at its earliest stages could prevent tumors from returning later, though studies have not yet established that benefit.
Cancer specialists already use several chemotherapy drugs as initial treatments for cancer, but they are not formally approved for the use. The FDA originally approved Perjeta to treat breast cancer that has spread to other parts of the body after surgery.
The FDA granted the drug accelerated approval for its new use based on a study showing women who received the drug as an initial treatment were more likely to be cancer-free 12 weeks later than women who received older drug combinations. Accelerated approval is reserved for drugs that show groundbreaking results for treating life-threatening diseases in early studies.
Signs the drug may have been heading towards fast-track approval appeared earlier in Sept. when FDA scientists issued a positive review of the drug days before a panel of outside cancer specialists was to review whether Perjeta's benefits outweighed its risks for treating early breast cancer.
The panel voted 13-0 with one abstention in favor of drug approval, and the FDA said it would decide on whether to accept the panel's advice by Oct. 31. Panel chairman Dr. Mikkael Sekeres of the Cleveland Clinic called the vote "a historic moment."
"It's an exciting drug because it targets a particular pathway in the cancer -- an 'on' switch if you will. About 15,000 women a year have this very aggressive cancer with this 'on' switch (a molecule called HER-2) and it turns it off. So targeted therapy is generally less toxic and really can have a major impact on the cancer," CBS News contributor Dr. David Agus, who leads the Westside Cancer Center at the University of Southern California, said on CBS This Morning earlier this month.
As a condition of approval, Roche's Genentech unit must conduct a larger follow-up study showing the drug's long-term benefits for patients. Generally that means showing that patients lived longer or had a higher quality of life due to taking the drug. Genentech, based in South San Francisco, Calif., has already enrolled about 4,800 patients in the follow-up study, with results expected in 2016.
The FDA said Monday's approval was based on a 417-woman study comparing Perjeta in different combinations against older breast cancer treatments. When Perjeta was combined with Herceptin, another Genentech drug, and standard chemotherapy, 39 percent of women saw their cancer reach undetectable levels. Only 21 percent of women experienced the same results from taking Herceptin and chemotherapy alone. After drug treatment all the women received standard breast surgery to remove any cancerous tumors. Genentech says this surgery allowed researchers to confirm the presence or absence of cancer.
Like Herceptin, Perjeta only works in a subset of about 20 percent of breast cancer patients who have tumors that overproduce a protein known as HER-2. This protein causes cancer cells to divide and grow faster than usual.
A spokeswoman for Genentech said a regimen of Perjeta plus Herceptin would cost between $27,000 and $49,000, depending on how long the patient takes the combination. The new Perjeta label will recommend a course of treatment between nine and 18 weeks.
Breast cancer is the second most deadly form of cancer in U.S. women, behind only lung cancer, and is expected to kill more than 39,000 Americans this year, according to the National Cancer Institute. About 6,000 to 8,000 deaths per year are attributed to the HER-2 form of the disease.
Breast cancer is highly treatable when detected early. More than 98 percent of women who are diagnosed with first-stage breast cancer survive at least five years, according to NCI figures.
The approval came one day before October's Breast Cancer Awareness month kicks off.