Good News about Blood Cancer Treatment
Leukemia gene therapy: a new stage
Alexandra Bruter, <url>Yesterday we wrote about the bad news: an experimental HIV treatment technique turned out to be ineffective.
But this is the nature of any untrodden paths: good luck alternates with failures, you have to overcome many unforeseen difficulties. It's the turn of the good news today.
In March of this year, ProScience talked about an experimental method for treating cancer of the lymphatic system developed at the University of Pennsylvania. Leukemias are diseases in which blood cells (mature cells or progenitor cells) begin to divide uncontrollably. This method is suitable for the treatment of diseases in which B-lymphocytes – those cells that normally produce antibodies - begin to multiply uncontrollably.
The method of treatment consists in taking their own T-lymphocytes from patients and modifying them in a test tube. T-lymphocytes are cells (not all, but a significant part of them) that recognize "by touch" sick cells of the body (cancerous, infected with a virus, etc.) and help them die. T-lymphocytes were modified so that they recognize and kill all cells on the surface of which there is a CD19 molecule, and it is on the surface of all B-lymphocytes: both healthy and sick.
The modified cells were injected back into the patients. Patients developed a typical, sometimes quite severe, picture of inflammation (the usual symptoms of a "cold" like high fever and general malaise are caused by the activity of T-leukocytes fighting infected cells). After some time, the state of health returned to normal and, if everything went well, there were no sick cells in the patient's body, and the modified ones remained – theoretically, for the rest of his life.
On their own, scientists conducted the first clinical trials on about a dozen patients, including two children. Emma Whitehead's happy story has bypassed many media outlets (she has been doing well for 20 months). Some patients went into complete remission, some had partial improvement. The treatment did not help two of them. If we consider that classical medicine with its chemotherapy and bone marrow transplantation could no longer help these people, then this is an amazing result.
But ten people are only ten people, and, for example, in 2000, a quarter of a million people fell ill with leukemia worldwide. No university can afford the full–scale clinical trials necessary to approve the drug for mass use - it is very expensive, and the cost of the method is high. But recently, the multinational pharmaceutical giant Novartis became interested in the method. On December 7, they published the results of already larger clinical trials. These results are extremely optimistic. Of the 22 children with acute lymphoblastic leukemia, 19 went into complete remission. In adult patients with chronic lymphocytic leukemia, improvements occurred in 15 out of 32 patients, of these 15 in 7 – complete remission (Porter et al., Chimeric Antigen Receptor–Modified T Cells in Chronic Lymphoid Leukemia).
This story is quite typical of modern drug development. First, scientists engaged in fundamental science clarify the situation. It was fundamental research that showed how T- and B-lymphocytes differ, how they interact with other cells, how the molecules look on their surface, in the course of fundamental research, the phenomena that formed the basis of cell modification were discovered. Then scientists engaged in applied science, who have a specific goal – to "come up with a cure for the disease", armed with fundamental knowledge, develop a method and show its effectiveness on a small group of patients.
Further, if the development looks promising, as a rule, large pharmaceutical companies come into play. Of course, they do this in the hope of future benefits, but we must understand that only a few drugs in clinical trials show themselves better than existing analogues, and, often, we are talking about a small superiority. The same story is notable for the fact that the method under study seems to be extremely effective so far, this is a great success both for the developer company and for future patients.
Portal "Eternal youth" http://vechnayamolodost.ru12.12.2013