– What exactly is immunotherapy?
It is a type of treatment that favors the cells of the patient's immune system to attack the tumor. It is not that it is a new investigation, because it has been investigated since the 70s, but had not yielded results until now because they were not very effective and, in addition, they were toxic.
Allison and Honjo have managed to overcome this barrier and have discovered how the tumor is able to stop the immune system, why the immune cells did not attack the tumor and why they were not able to recognize it as an external agent.
– How do they attack the tumor?
The T lymphocytes work like soldiers, they are in charge of attacking the tumor, but to do it, they have to recognize it and attack it.
Allison has discovered the protein so they did not activate and Honjo found another one that is responsible for the tumor to deactivate this "attack". They are two independent studies, but with the same effect.
– In what types of cancer is it effective?
The antigen discovered by Allison, CTLA4, is used for drugs that attack melanoma and lung cancer.
The PD1 protein, discovered by Honjo, has proven its efficacy in melanoma, in non-small cell lung cancer, in head and neck, Merckel carcinoma, renal and is being investigated for the rest.
– With what type of cancer have not good results been achieved?
With pancreas there are still no positive results because they have not been able to overcome the tumor microenvironment (the environment surrounding the tumor cell). They have not been able to break through this barrier and reach the tumor, as with many brain cancers that the drugs do not reach.
There are others, such as the breast, that do not have many mutations, the immune system does not identify it, does not detect the danger and that is why immunotherapy is not effective, but in breast chemo works very well.
– Is it used as a single or combined treatment?
Now the two forms are used because it can be more effective with these two approaches, but in some cases it is only treated with immunotherapy, such as melanoma.
– How many medications are there now?
There is a wide variety of approved drugs, and many others in research, such as the vaccine in which they are working.
– Is this approach more expensive than chemo or radiotherapy?
Yes, much more, since its development is more expensive, since it is a genetic modification. For example, four injections of Ipilimumab (using CTLA4 protein) to treat melanoma costs about 80,000 euros, but does not need any further treatment.
– Are patients reluctant to this new approach?
No way! Quite the opposite. They come asking for it and ask about clinical trials in which they can participate.