Promising developments emerge in cancer research
September 28, 2017
On Aug. 30, the Food and Drug Administration green-lighted the first gene therapy for leukemia, a landmark decision that opened the door to a new wave of cancer treatments.
Revolutionary in its approach, the treatment, marketed as Kymriah by Novartis Pharmaceuticals, will be administered to a group of children with relapsed acute lymphoblastic leukemia (ALL). Instead of using external methods to fight cancerous cells, it further enables the body’s immune system as a weapon by harvesting the body’s lymphocytes, or white blood cells, and re-engineers them to recognize antigens on targeted cells and destroy them. These lymphocytes, now referred to as CAR ‘chimeric antigen receptor” T-cells, are reinfused into the patient where they kill the cancerous cells in their midst and later prevent recurrence (FDA).
Of the 3,100 new cases of ALL treated each year, standard therapy can achieve a complete remission for most, but in the case of a relapse, the chances of a successful treatment are slim, making the results for Kymriah even more noteworthy (Scientific American). According to the Guardian, in clinical studies, CAR T-cells eliminated cancerous cells from up to 90 percent of the participants, all of whom had relapsed multiple times or didn’t respond to the standard therapies that were administered. The impact of gene therapy has the potential to spread far beyond ALL, as studies show that it can potentially destroy cancers ranging from Multiple Myeloma to brain tumors.
Kymriah remains the frontrunner of its kind but according to the Alliance for Regenerative Medicine, 470 potential treatments are unfolding under initial clinical trials with another 34 in the final stages of FDA approval testing, signaling a future where competent treatments can provide a viable alternative to mainstream treatments. These well-known therapies, including chemotherapy, radiation and immunotherapy, have served as the precedent for cancer treatment over the last few decades, but are incredibly flawed. In a nutshell, these methods target cancerous cells through a process called apoptosis, in which proteolytic enzymes, caspases, are activated by chemicals or high energy rays, and proceed to trigger cell death by splitting specific proteins in their nuclei and cytoplasm. However, apoptosis often fails to eradicate a portion of cancerous cells, leading to a high risk of relapse, leaving the body’s healthy cells severely weakened.
To eliminate the potential of cancer recurrence and damage to the healthy cells, scientists in Glasgow, England developed Caspase Independent Cell Death (CICD), which sends a signal to the immune system to obliterate the last of the cancerous cells (University of Glasgow). Even though this treatment has only been focused on colorectal cancer, as with CAR T-cell therapy, it can be further tailored to defeat a wider array of cancers in the future.
Before exclaiming a preliminary cheer, scientists realized the complexities of such treatments, as with most others in this domain, threaten to overshadow the benefits. Novartis set the cost of CAR T-cell therapy an upwards of $475,000 (Business Insider) a sum that sits in stark contrast to chemotherapy’s average of $30,000, the group Patients for Affordable Drugs deemed “excessive” (WebMD). While Novartis made steps to offset the price by setting up a patient-assistance program and promising to not charge patients for the treatment if they don’t respond to it.
Ms. Katherine Huang, Dougherty’s Biotechnology teacher, argues the enforcement of the treatment will continue to be “a long expensive process” due to the chemicals used, the molecules that need to be synthesized and the training of physicians to administer and interpret it.
While the cost alone doesn’t bode well for the future of this treatment, the sometimes fatal side effects might be a deal breaker; the newly infused T-cells can kick off a cytokine storm, a reaction that can cause a high fever and a dangerous drop in blood pressure, neurological problems and other complications that lead many patients to a precarious position between life and death before they finally recover. While its adeptness at destroying cancer cells is certain, the FDA still has to actively assess if Kymriah results in the creation of another health issue.
The future of CICD is even more vague, as the treatment may not see the light of day; though they have potential, most treatments don’t tend to make it past the various rounds of FDA approval. Although researchers are hopeful about the future of CICD, years of further research and clinical trials are still required before the therapy can ever hope to become mainstream.
Huang cautions against the idea that these treatments may lead to a cure, explaining her belief that “There’s no magic bullet for cancer. Cancer is something [in which] all cells die, and all cells mutate, and it’s kind of a natural form of evolution … You should think about [a cure] in terms of treatments, like what kind of methods are there to kind of alleviate cancer.”
Nevertheless, these treatments promise to change the future of cancer treatments by offering a targeted approach to cancer cell death; while skepticism does exist, these therapies bring researchers one step closer to solving a problem often deemed unsolvable.