The Rocky Beginnings of Personalized Medicine
In late August, a renowned therapeutic drug known as Kymriah was approved by the FDA. Specifically, this drug was approved for patients with B-cell acute lymphoblastic leukemia, a form of cancer most prevalent in children. The therapy entails a re-engineering of the patient’s own immune cells in order to be prepared to combat cancer. Heralded as the “first gene therapy” in the U.S., the drug developed by Novartis astounded the science community. The prospect of gene therapy has surely been amped up by recent breakthroughs in gene editing methods such as CRISPR/Cas9. But, this event proved to be the first-ever, formal materialization of the concept in the U.S. Now, just a few months after, we’re seeing another gene therapy developed by Gilead now being approved by the FDA. This recent turn of events begs the question if we’re finally doing justice to the immense potential that gene therapy can have in the context of medicine.
"From CRISPR/Cas9 to Kymriah, the right pieces seem to be coming into place for a revolutionary institution of gene therapy nationally and hopefully globally."
One potential hurdle behind such novel gene therapies is the level of personalization involved. There’s obviously nothing wrong with personalized treatment: in fact, that’s a step that medicine should take and is gearing towards taking in the near future with the aid of technology. But, the process for a new drug like Kymriah or Gilead’s new therapy is that each “drug” is not necessarily an ordinary pill that you can simply pop in while you move on with your life. The doctor actually has to acquire a sample of your white blood cells before re-engineering them and eventually re-administering them in the patient. That process can take almost three weeks, a disadvantage not too dissimilar with the conventional trial-and-error nature that current drugs can have. Without a robust system of personalization, this would not be a sustainable operation. Novartis’s therapy has also proven to be supremely difficult to mass-produce. According to Business Insider, such factors contribute to the therapy’s exorbitant price of $475,000, making for a therapeutic regimen that only 600 people can get per year. Kymriah has simply not been thought through enough for this approval and the approval of Gilead’s therapy to have a lasting impact.
We can definitely rectify our system with regulations that can ensure such operations for gene therapies can be as efficient as possible. What might not seem as corrigible would be the side-effects that would inevitably come with any gene therapy. One of the reasons why gene therapy was essentially banned globally was due to the side-effects that came to light in a 2000 trial in France. A three-year old patient who was seemingly cured of his severe combined immunodeficiency (SCID) soon developed leukemia. The treatment was not specific enough to target the correct portion of the patient’s genome, resulting in a cataclysmic sabotage of genes crucial for controlling cell division and preventing cancer. It’s true that Kymriah and Gilead’s treatment are both giving the second chances to patients that conventional medicinal practices can’t. But, in phase 2 clinical trials, a common side-effect of re-engineering T-cells to fight cancer was a condition known as cytokine release syndrome. The condition mostly entails a seemingly innocuous excess of inflammation-inducing molecules known as cytokines. The symptoms such as fever don’t seem to be too grave, but we can’t oversee correctable side-effects as trivial again. For the future of gene therapy as well, another tragic mishap would most certainly doom gene therapy’s use for yet another decade. Again, we see a minor hitch in the dream of personalized medicine. Personalization leads to less uniformity across different therapeutic situations, which translates to a lessened ability to regulate and possibly correct the treatment in every individual case.
In an official statement, FDA Commissioner Scott Gottlieb said that “gene therapy has gone from being a promising concept to a practical solution to deadly and largely untreatable forms of cancer.” Gene therapy undoubtedly retains a place on the front lines in the future of medicine. From CRISPR/Cas9 to Kymriah, the right pieces seem to be coming into place for a revolutionary institution of gene therapy nationally and hopefully globally. But, at the same time, we need to be vigilant of the accessibility and safety regarding this novel, but powerful therapy.