Perjeta is a new drug which could significantly assist patients experiencing advanced breast cancer.
Roche, a pharmaceutical developer created the drug, which is being heralded as an "unprecedented" advance in extending the lives of women suffering from breast cancer. A clinical trial of the new medicine showed such promising results that health experts are urging its use for patients facing one of the most dangerous forms of breast cancer.
Roughly one-quarter of all breast cancer patients are diagnosed with the HER2 positive form of the disease.
Herceptin and chemotherapy are the usual treatments prescribed for women with HER2 positive cancer.
The new study examined women taking Perjeta in addition to current treatments, and compared them to patients undergoing just chemotherapy and doses of Herceptin. Patients with metastatic cancer - which has spread to other parts of the body - were examined in the clinical trial that involved more than 800 women.
Researchers found patients treated with Perjeta, also known as pertuzumab, lived an average of 56.5 months, an improvement of 15.7 months over the 40.8 month average lifespan of those who did not take the new drug. These results equate to a 32 percent improvement in survival rates for those using the new treatment. This is not only unprecedented metastatic breast cancer, but is an extremely good result for any drug meant to treat cancer that has spread.
Pertuzumab was approved by federal regulators for public use in 2012. Previous studies showed the drug extended the amount of time women were able to live without the disease becoming worse, known as progression-free survival. Researchers had to wait to accurately measure long-term survival rates of the patients.
Herceptin and Perjeta each work by blocking the actions of the HER2 protein which is manufactured by the gene linked to the cancer. However, each drugs links to different parts of this protein, lending support to treatment methods using drugs that independently treat disease.
"The results, I think, are phenomenal. The survival improvement of nearly 16 months... is unprecedented among studies of metastatic breast cancer," Sandra Swain of the Washington Hospital Center, and lead researcher on the study, stated to attendees at an annual congress of the European Society for Medical Oncology (ESMO).
Side effects of Herceptin and Perjeta include increased heart problems, diarrhea and rash. However, use of the two drugs in tandem was shown not to increase the risk of these side effects.
Both drugs are injected by a doctor, and treatment is expensive, costing over $5,000 a month. Perjeta is expected to reach sales of $3.1 billion a year by 2018.
