FDA Approves First Genetically-Modified Cell Therapy to Treat Leukemia
Carl Simon Jr.
The FDA approved the first genetically-modified cell therapy for the treatment of leukemia on August 30, 2017 [1-2]. The treatment (tisagenlecleucel) is an "autologous genetically modified immunocellular therapy indicated for the treatment of pediatric and young adult patients 3 to 25 years of age with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (ALL)" . B- cell acute lymphoblastic leukemia is the most common malignancy diagnosed in children. The treatment is a chimeric antigen receptor (CAR) T-cell therapy, where the patient's T cells are genetically modified to express a CAR which targets CD19 which is expressed by B cells. For the treatment, cells are harvested from the patient via leukapheresis and shipped to a manufacturing facility where they are engineered to express the CAR against CD19. The manufacturing process takes 22 days and then the modified cells are shipped back to the hospital where they are administered to the patient. The potency test for release of manufactured batches is the measurement of interferon-γ production upon stimulation by CD19+ cells. The interim endpoint in the pivotal study showed remission in 52 of 63 patients (P < 0.001, 95% confidence interval 71% to 91%) . The cost of the treatment is reported to be $475000 .