CHIMAERA: The mythical monster that fights cancer. We hope

In the main square of Quito, Ecuador

 

A new article in the Wall Street Journal has a direct bearing on some of the questions we have been stumbling over for several months, specifically: .  What kind of cancer treatment offers the most hope, and how can we pay for it.  Here’s the article:

http://online.wsj.com/articles/new-costly-cancer-treatments-face-hurdles-getting-to-patients-1412627150?KEYWORDS=Novartis

The treatment described in this article  has been developed specifically for acute lymphoblastic leukemia, a common childhood leukemia (adults also are susceptible.)  However, it might prove useful in the case of other types of cancer.  It (the treatment) is highly specific to the individual patient – in other words, it isn’t possible (yet?) to affect economies of scale, by mass-producing a drug that would benefit everybody.  Instead, here is how it works, more or less:  (1) A blood sample is drawn from the patient; (2) A type of white blood cell called a T-cell is separated;  T-cells are part of the body’s inherent immune system; (3) The T-cells are modified by inserting (using virus "vectors") some alien DNA that will recognize and fight the cancer;  (4) These modified T-cells are cultured for a time, producing lots of them; (5) Finally, this new T-cell army is re-inserted into the patient, whereupon it seeks out the cancer cells and destroys them.  Hallelujah!  But curb your enthusiasm: so far this therapy has been applied to only 41 patients, in two separate Phase 2 trials.  The results have been exemplary so far, but a lot of testing still remains to be done – even though NIH has “fast tracked” this study.  (Three years instead of six?  I tend to be cynical about such matters.)  One important fact that remains to be determined is – is the “cure” permanent or temporary?

Another problem lies in the realm of adverse reactions.  A similar study recently conducted found that patients at risk for heart disease had a tendency to die when the modified T--cells are re-injected`.  They died of something called “cytokine-release syndrome”.  You can look it up on Wikipedia.  If you do, explain it to me.

Oh, by the way – these GMO T-cells are referred to as “CARs, which codes for “chimeric antigen receptors”.  “Chimeric”, in turn, refers to the fact that the modified T-cells are “Chimaera” – composed of two or more types of genetic material.    An “antigen” is something that “generates” an antibody (which are the dudes that fight infection.)  “Receptor” seems to refer to proteins or other stuff on the surface of cells that are shaped precisely to allow certain floating antibodies (or other kinds of cells) to fit into them, thereby precipitating  some kind of internal biochemical process.  That’s what the three words mean.  If you figure out what they mean when strung together, please let me know.

And, oh yes, the cost:  Nobody has come out with a definite number yet, but the estimates cluster around $½ million per patient.  Let's puzzle about that later.