By: Anna Diyamandoglu, PharmD Candidate c/o 2020
The specificity of individuals’ genetic makeup has been one of the primary obstacles facing healthcare professionals in their attempt to treat cancer patients. Cancer is at the forefront of disease states which have proved difficult to understand and treat due to each patient’s unique genetic makeup and how the same type of cancer can develop differently in different patients. Individualized treatment of certain cancers, such as leukemia, using gene therapy – insertion of genes into an individual’s cells and tissues to treat a disease – has long been considered as a potential way to overcome the obstacle of genetic specificity in patients.1
This past August 2017, the FDA approved the first gene therapy tisagenlecleucel (Kymriah ™). Manufactured by Novartis, tisagenlecleucel is the first approved CAR-T cell therapy for patients up to 25 years old with second or later relapse or refractory B-cell Acute Lymphoblastic Leukemia (ALL).2 ALL is a cancer in which the bone marrow produces too many immature lymphocytes; it is the most common childhood cancer in the United States and progresses very quickly.3 Traditional treatment involves chemotherapy, radiation, and if necessary, a bone marrow transplant from a related or unrelated donor.
Tisagenlecleucel is customized to match each patient’s own T-cells. T-cells are removed from the patient’s bloodstream, frozen, and sent to Novartis’ manufacturing center where they are genetically modified to include a new gene that contains a specific chimeric antigen receptor (CAR).4 These receptors allow the patient’s T-cells to target and destroy leukemia cells that contain the surface antigen CD19. Once the modification has been made, the cells are frozen and shipped back to the institution where the patient is treated for administration. The FDA is requiring that all institutions that prescribe and dispense tisagenlecleucel be specially certified.5
Throughout its experimental and clinical trial phases of development, tisagenlecleucel showed great potential in terms of the prognoses of pediatric ALL patients. The first patient to be administered this treatment, Emily Whitehead, was six years old and near death when her physicians at the Children’s Hospital in Philadelphia decided to try the therapy as a last resort in 2012. She is now 11 and has been cancer free for five years.4 Additionally, in a clinical trial involving multiple health care institutions which included 63 pediatric ALL patients, the overall remission rate within three months of treatment was 83% – an astoundingly successful rate.5
While the approval of tisagenlecleucel has the potential to help many young leukemia patients, it has several side effects: hypotension, high risk of infection, hypoxia, acute kidney injury, and a black boxed warning for cytokine release syndrome (CRS) which causes fever and flu-like symptoms that can be life threatening if left untreated.5
With the approval of tisagenlecleucel, the option for gene therapy treatment has gone from being simply an idea to an implementable option for patients. Regarding the ground-breaking approval, FDA Commissioner Scott Gottleib, M.D, stated, “We’re entering a new frontier in medical innovation with the ability to reprogram a patient’s own cells to attack a deadly cancer.”5 Indeed, approval of tisagenlecleucel (Kymriah ™) is a leap forward for cancer research and opens a door to the limitless potential gene therapy has in making historically incurable diseases now curable.
- Tontonoz, Matthew. “Model Ts: FDA Approves First CAR T Cells for Cancer.” Memorial Sloan Kettering, Memorial Sloan Kettering Cancer Center, 30 Aug. 2017.
- “KYMRIAH™ (Tisagenlecleucel).” KYMRIAH® (Tisagenlecleucel) | NOW FDA APPROVED, Novartis Pharmaceuticals, 30 Aug. 2017.
- “Childhood Acute Lymphoblastic Leukemia Treatment.” National Cancer Institute, National Cancer Institute, 17 Aug. 2017.
- Grady, Denise. “F.D.A. Approves First Gene-Altering Leukemia Treatment, Costing $475,000.” The New York Times, The New York Times, 30 Aug. 2017.
- “Press Announcements – FDA Approval Brings First Gene Therapy to the United States.” U S Food and Drug Administration Home Page, Office of the Commissioner, 30 Aug. 2017.