Two new analyses of two new breast cancer drugs found that they are indeed worth what you pay for them.
The aromatase inhibitor Aromasin (exemestane) and the monoclonal antibody Herceptin (trastuzumab) have already been proven in clinical trials to improve survival.
As new breast cancer drugs exit the pipeline and enter the market, the U.S. health-care system, including the insurance companies or governments paying for therapy, want to know if the drugs are economically, as well as clinically, viable. And new drugs are almost always more expensive compared to the usual standards.
"This is always important to do when you have a drug or a procedure or intervention that is expensive compared to standard care," said Nicole Mittmann, senior author of the Aromasin study, and a scientist with Sunnybrook Health Sciences Centre and assistant professor of pharmacology at the University of Toronto. "The clinical data still drives the decision to use the medication, and this is another piece of the puzzle in the decision-making process."
Dr. Jay Brooks, chairman of hematology/oncology with Ochsner Health System in Baton Rouge La said, "The clinical research trials we've done in the last 50 years have been spectacular, and we know how good or how not good our treatments are, and because of the excellent clinical research that's been done, we can then ask ourselves can we afford these treatments."These two studies involving Herceptin and Aromasin clearly show that doing these two maneuvers are very, very cost effective in certain subgroups of women with breast cancer. When insurance companies come to you and ask why are you doing this, you have excellent studies to back them up," he added.
A large clinical study had already shown that women with hormone-receptor-positive breast cancer who switched from tamoxifen to Aromasin after two to three years lived longer than women who took tamoxifen continuously for five years.
But aromatase inhibitors are more expensive than tamoxifen, which has been around for years. And aromatase inhibitors do have some side effects, including musculoskeletal problems such as osteoporosis and fractures.
"Tamoxifen is pretty cheap. Aromasin is newer and more expensive," Mittmann said. "Is the added cost worth the added benefit?"
Cost-effectiveness is measured in number of life years gained and is also adjusted for the quality of life gained, expressed as quality-adjusted life year (QALY).
In Canada and elsewhere, the commonly accepted threshold for a QALY is $50,000 (Canadian dollars).In this case, the authors found that using tamoxifen and Aromasin sequentially for five years (after 2.5 years of surgery and other standard therapies) improved disease-free survival at an additional cost of $2,889 (Canadian) per patient. This translates into an incremental cost-effectiveness ratio of $24,185/QALY gained, well below the $50,000 bar.
"If this is $24,000, it seems to make sense that this is good value for money," Mittmann said.
According to Mittmann, the model would be applicable to the U.S. market.
The authors of the second study estimated that women would gain three years of life, on average, by adding Herceptin to therapy.
Over a woman's lifetime, the cost-effectiveness ratio would be $26,417/QALY (U.S.), again, below the commonly accepted threshold.
The Aromasin study was funded by an unrestricted grant from Pfizer Inc., which makes the drug. The Herceptin study was funded partly by Genentech, which makes Herceptin.