Any news story that includes the words “disappearance” and “cancer” in one sentence is good news. Therefore, the results of a small clinical trial conducted recently in the United States are a welcome wave of hope. Twelve patients with rectal cancer. They received a drug immunotherapy which was previously used in other tumors, such as endometrium, but never been used with this one. And the best thing is that each and every one of them saw how his cancer disappeared after the treatment.
Six months later, there was no trace of her tumors.s neither in MRIs, nor in PET scans, nor in endoscopy. Nor in the biopsies that they were taken. Apparently, thanks to this treatment the cancer had disappeared.
The results of the clinical trial have been described with great optimism In a study published in the New England Journal of Medicine. However, even with these positive data in hand, its authors remind us that it is necessary to stay cautious. On the one hand because the number of participants has been very small and on the other because, even though six months have passed, it is still early days. cannot be ruled out over time the cancer reappears. Even so, it is great news that gives them a great thread to keep pulling, adding more participants and completing the rest of the phases of clinical trials.
Silence at checkpoints
The drug in question is called dostarlimabalthough it is marketed as jemperli. It is an immunotherapy medication, one of those known as inhibitors of checkpoint.
These checkpoint either checkpoints are parts of immune system dedicated to this not getting out of hand and attacking what it shouldn’t. They basically consist of a group of proteins that are attached to the T lymphocytes, cells of the immune system that intervene in different ways in the attack on foreign agents. These proteins attached to them recognize other proteins present in the cells of the organism. If they recognize each other, a signal is sent turns off to the T lymphocytetelling it not to attack that cell.
So far so good. The problem is that tumor cells also have these proteins. Furthermore, they are able to overstimulate those checkpoints, so that the immune system does not attack the tumor and it can continue to proliferate without problems. For this reason, many cancer treatments focus on inhibiting these checkpoints, so that it is the patient’s own immune system the one in charge of ending the tumor.
Jemperli, manufactured by the pharmaceutical company GlaxoSmithKline, is one of the drugs that act in this way. It had been previously tested with endometrial cancer, with good results. But until now he had not been tested for rectal cancer. Now, thanks to this little clinical trial, we know that he was a good candidate.
Why rectal cancer?
The area in which the rectal tumors are located favors a very wide range of secondary effects derived from chemotherapy and radiotherapy. These range from digestive problems to incontinence, infertility and sexual dysfunctions.
For this reason, it was thought that it might be useful to resort to a treatment based on immunotherapy, such as this inhibitor of checkpoint. To check it, in Memorial Sloan Kettering Cancer Center (MSK) in New York A clinical trial was launched in which twelve people with rectal cancer initially participated. As a common factor, they all had tumors with the MMRd mutation, which is characterized by lower sensitivity to chemotherapy and radiotherapy. Surgery is usually your only option and it is not always possible to completely remove the tumors.
But they also have a positive side and that is that they are more sensitive to immunotherapy. Therefore, it was expected that Jemperli would be effective. What was not clear is that he could be so highly effective. And it is that after six months there was no no trace of the tumor in none of them. Also, hardly any side effects and the few that were reported were very mild.
This is the phase II clinical trial, so it is still early to launch the bells on the fly. It is expected that in the following phases they will register at least 30 people. It would be ideal to go even further. And, of course, the efficacy of the treatment should also be tested in people with rectal cancer without the MMRd mutation. These are all the reasons for caution that we talked about at the beginning. But there are also reasons for hope. Many, in fact. Therefore, we can undeniably say that what these scientists have just published is great news.