On September 17, 2013, the Cleveland Clinic announced that it would bring the preventive breast cancer vaccine developed by Professor Vincent Tuohy of the Cleveland Clinic in 2010 forward to the FDA for permission to begin clinical trials to see if it is safe and effective for use in women.
The vaccine was shown to be completely safe and100% effective in preventing breast cancer in three animal models (Nature Medicine, May 2010), and was also found to slow the growth of tumors that had already formed. The vaccine is especially powerful in inhibiting the growth of triple-negative breast cancer, the most aggressive form of the disease with the lowest survival rate. Triple-negative breast cancer lacks estrogen, progesterone and Her2 receptors. It occurs in approximately 15% of cases and is also the kind of breast cancer most commonly found in women who carry a BRCA mutation.
The initial clinical trials, called Phase I studies, will be conducted in two groups of volunteers, women with triple-negative breast cancer who have completed their treatment and are free of disease, and women who will be vaccinated shortly before undergoing bilateral prophylactic mastectomy. (The second group will likely be comprised of those, like Angelina Jolie, who carry a BRCA mutation and have elected to remove their breasts to lower their risk for cancer.) The first group of women will be studied to determine the dose and effectiveness of the vaccine; the second group will be studied to make sure the vaccine does not trigger an abnormal immune response in their breast tissue.
The vaccine targets a unique protein normally made only by women who are breastfeeding, alpha lactalbumin (ALA). In the 12 years Tuohy spent developing and researching his vaccine, he discovered that the majority of breast tumors express, or make, ALA. Priming the immune system with a vaccine so that it attacks any cell that makes ALA is the method by which Tuohy’s vaccine works. Because the vaccine targets ALA, a protein necessary for successful lactation in healthy women, the vaccine would not be appropriate for use in women who are still in their childbearing years. However, the majority of women diagnosed with breast cancer in the United States and other western countries are post-menopausal: at least 60% of the cases of breast cancer in the United States occur in women over 55; thus, Tuohy’s vaccine, if proven safe and effective, would constitute the first preventive vaccine applicable for the majority of women in this country and elsewhere. Because the vaccine has also demonstrated therapeutic potential (in slowing the growth of tumors that have already formed), it may also prove useful in treating women who already have the disease, particularly women with triple-negative breast cancer for which there are presently no available targeted therapies.
Other scientists have joined the movement toward creating effective breast cancer vaccines. Dr. Brian Czerniecki of the University of Pennsylvania has an effective therapeutic vaccine used to treat women with ductal carcinoma in-situ whose tumors express the growth receptor, Her2. And two years ago, Dr. Susan Love and the National Breast Cancer Coalition began working with a panel of scientists on the Artemis Project whose goal is to develop a breast cancer vaccine capable of ending all breast cancer within seven years.
Given that the global burden of breast cancer is a crushing and growing weight on women, their families, and economies, and given that there is at present no targeted therapy available for women with triple-negative breast cancer or for those who carry a BRCA mutation, I fully expect that the FDA will allow clinical trials of the Cleveland Clinic’s preventive breast cancer vaccine to proceed along its Fast-Track process instituted in the 1980’s in the wake of the AIDS epidemic. The FDA’s Fast-Track process is not to be construed as less demanding than the normal approval process. On the contrary, it is every bit as strict as the (glacial) process by which all other drugs, devices, and vaccines are approved. The notable difference between the FDA’s Fast-Track process and the normal approval process is that Fast-Tracking accelerates the rate at which the paperwork and guidance are given when a new intervention such as the Cleveland Clinic’s preventive breast cancer vaccine has the potential to fill a void – like the one that exists for BRCA carriers and women with triple-negative breast cancer.
We must keep in mind that not everything that works in mice works in women. As Dr. Francis Collins, Director of the National Institutes of Health, said to me last week at the annual meeting of the Clinton Global Initiative in New York City, “We’ve cured cancer a thousand times in mice!” Right. And yet we’re still running in circles in the race for a cure. On the other hand, everything that currently works in humans first worked in mice, so there is hope. But hope must be tempered with an evenly realistic appraisal of the likelihood of success of this, the world’s first preventive breast cancer vaccine.
Fortunately, we don’t have to debate or speculate or continue the harangue about the potential of this vaccine, for now we have the money to simply test it and see if it works. Using the scientific method and the most rigorous application of the rules appropriate for human trials, we can let the vaccine speak for itself.
The prospect for legitimate hope posed by this vaccine is good news for women with triple-negative breast cancer and women with a BRCA mutation and the women who are at risk for this disease – which is all of us. I expect that given the orphan status of triple-negative breast cancer, and given that women with a BRCA mutation have little else but to have their breasts and ovaries amputated in the effort to reduce their risk, that the FDA will allow the vaccine to speak for itself, quickly, by allowing it to proceed along its Fast-Track process and into clinical trials quickly, before, say, the polar ice caps melt and freeze again.
The sooner we know, one way or another, if this preventive vaccine is safe and effective, the better off we all will be.
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