Patients at the McGill University Health Centre (MUHC) are the first in Canada, and among the first in the world, to test the effectiveness of a technology based on mRNA to fight the most common form of lung cancer.
These randomized clinical trials are aimed more specifically at patients who have been diagnosed with stage II or III non-small cell lung cancer and who have undergone surgery.
“Stage II or III cancers are curable, but there are often micrometastases (that we miss),” explained Dr. Jonathan Spicer of the MUHC. “For 75 per cent or more of these patients, there are cells that will lodge in the brain, in the bones, in the adrenal glands and elsewhere, and the majority (of patients) will have a recurrence.”
This is why, he added, “we are trying to add other treatments that will attack these micrometastases,” especially since the progress made in lung cancer screening is making it possible to identify more and more patients whose disease is at these stages.
“We don’t want to overtreat patients who will be cured, but we are trying to prevent (a return of the cancer) in high-risk patients,” Spicer said.
All patients participating in these clinical trials are treated with chemotherapy and immunotherapy either before or after surgery to remove their tumor.
After surgery, the tumor is analyzed in the laboratory to identify its genetic characteristics and the proteins derived from them – called neoantigens. This makes it possible to develop an mRNA with sequences specific to these neoantigens that is then injected into the patient.
The strategy is part of what is known as “precision medicine” or “personalized medicine,” which involves tailoring treatments to a patient based on their genetic makeup or disease characteristics.
Immunotherapy, Spicer explained, helps the immune system find and destroy residual cancer cells that may be lurking in the body after surgery and other treatments. The answer isn’t perfect, though. Researchers hope the new, personalized therapy will take the immune system to new heights of effectiveness.
“You’re adding a vaccine to a patient’s immunotherapy,” he explained. “It’s activating the immune system so it can recognize (neoantigens). Hopefully, it’ll reduce recurrences, increase survival rates, and so on.”
Messenger RNA entered popular jargon during the COVID-19 pandemic, when the technology led to the development of vaccines against SARS-CoV-2.
The clinical trials that are now being conducted at the MUHC are directly linked to the progress made during that global health crisis, Spicer said, since it led to the development of cancer vaccines that have already shown their effectiveness against melanoma.
The hope is now that the same will be true for lung cancer.
“There is no doubt that we have learned a lot about these technologies (during the pandemic),” he explained. “And now, we are applying them not only to infectious diseases, but to diseases like cancer, and we already have preliminary evidence that it can work. And if it can work in the context of lung cancer, that would be a huge advancement in a cancer that is very common and still kills a lot of people.”
–This report by La Presse Canadienne was translated by CityNews
