It is a decision that will make a great noise in oncology. Wednesday, 12 July, a panel of ten experts of the american Agency of medicines has unanimously recommended the approval of CTL019, a treatment for lymphoblastic leukemia, which is based on CAR-T. With this method, the swiss laboratory modifies the T-lymphocytes (or T cells) from a patient in vitro to help them to recognize the antigen of a tumor and attack it. A therapeutic method which is based on immunotherapy, stimulation of the immune defenses and engineering of the genome.
In April, the treatment of Novartis had been designated as a “breakthrough therapy” by the FDA. With the view of the panel of experts, the swiss laboratory could get the 3 of October, the green light from the FDA to market this treatment, which is expected as a blockbuster-more than a billion dollars of revenue per year. If all goes well for Novartis, CTL019 will be the first treatment based on the engineering of the genome to be launched on the market. Another therapeutic product, the Zuma-1, also operating with Car-T against the aggressive lymphomas-Hodgkin’s and designed by Kite Pharma, could arrive on the us market on November 29.
The percentages of remission are very high
The results obtained for the AS-T are very encouraging on paper. In phase II, the treatment of Novartis has generated 93% (55 patients out of 59) resulting in complete remission for patients with lymphoblastic leukemia at an advanced stage with a median follow up of 12 months. The side of Kite pharma, one-third of patients responded fully to treatment. The signs of cancer had disappeared, after 8.7 months of follow-up in median value. The survival rate at six months in patients with aggressive lymphoma Hodgkin’s disease is only 50% at six months, usually.
We can also mention a study presented at Asco, the largest congress of cancerology in the world in June, and led by dr. Wanhong Zhao, hematologist from the university of Xi’an. It mentions a remission in 33 patients (35) through the use of CAR T against multiple myeloma. These have been followed up for two to fourteen months.
Side effects sometimes serious
In addition to the low number of patients who have received CAR-T, it is difficult to know the long-term performance of this treatment strategy, due to the length of follow-up in clinical trials. Moreover, this therapeutic method has to meet two big challenges. On the one hand, the patients treated by the modified T cells have significant side effects, causing many scientists to focus their research on solutions to reduce it.
Kite Pharma has secondary effects serious in its latest clinical study, that is to say, grade 3. Thus, 43% of patients developed anaemia, 39% developed neutropenia (a sharp drop in the rate deglobules white in the blood). And three patients died of causes not related to the progression of the disease. The laboratory Juno was forced to stop a clinical trial of its treatment for lymphoblastic leukemia, following the death of three patients. Novartis found no deaths related to treatment, but noted “syndrome of cytokine-release syndrome” resulting in fever intense, great fatigue, and at the risk of respiratory failure, up to death.
Yet, medicines of Kite and Novartis are about to arrive on the american market, so that they are not in phase III (last-stage of clinical trials before a medicine is marketed). The FDA believes that in view of the seriousness of the diseases concerned (there are no other therapeutic alternatives for these, at a stage of the disease advanced), the expected benefits justify the risks taken. She thought, however, to the establishment of a platform to collect and analyze the risks represented by the As-T.
The question of the cost
The second challenge of weight faced by the us market -in particular, patients and payers – is the exorbitant cost announced of this type of treatment. It could exceed the $ 500,000 per patient, according to analysts, One Citigroup. The boss of Juno abounds, considering that the cost would vary between 500.000 and 750.000 dollars. In comparison, the new immunotherapies against lung cancer called “non small cell” can cost more than $ 20,000 (price of a facial, likely to be negotiated down with the insurers) for six weeks of treatments.
The pharmaceutical companies emphasize the breakthrough therapeutic that these treatments would, to justify such amounts. But also the process is long, complex, individualized, and, therefore, costly to modify the T cells and reinjecting it into the patient..