Demonstrating an mRNA Cancer Vaccine
One of the consequences of the COVID-19 pandemic is that the biotech industry is now geared up for the use of messenger RNA (mRNA) as a basis for therapy. The broadest use at present is vaccination, as doses can be very low and the experience gained during the pandemic is directly applicable, but many other forms of mRNA gene therapy are under development. Given the ability to produce novel mRNA vaccines, the most obvious use beyond infectious disease is to force the immune system to engage with cancerous tissue. This line of development appears to be making good progress.
In a first-ever human clinical trial of four adult patients, an mRNA cancer vaccine quickly reprogrammed the immune system to attack glioblastoma, the most aggressive and lethal brain tumor. While too early in the trial to assess the clinical effects of the vaccine, the patients either lived disease-free longer than expected or survived longer than expected. The results mirror those in 10 pet dog patients suffering from naturally occurring brain tumors whose owners approved of their participation, as they had no other treatment options, as well as results from preclinical mouse models. The breakthrough now will be tested in a Phase 1 pediatric clinical trial for brain cancer.
This is a potential new way to recruit the immune system to fight notoriously treatment-resistant cancers using an iteration of mRNA technology and lipid nanoparticles, similar to COVID-19 vaccines, but with two key differences: use of a patient's own tumor cells to create a personalized vaccine, and a newly engineered complex delivery mechanism within the vaccine. "Instead of us injecting single particles, we're injecting clusters of particles that are wrapping around each other like onions, like a bag full of onions. The reason we've done that in the context of cancer is these clusters alert the immune system in a much more profound way than single particles would."
In a cohort of four patients, RNA was extracted from each patient's own surgically removed tumor, and then messenger RNA, or mRNA - the blueprint of what is inside every cell, including tumor cells - was amplified and wrapped in the newly designed high-tech packaging of biocompatible lipid nanoparticles, to make tumor cells "look" like a dangerous virus when reinjected into the bloodstream and prompt an immune-system response. The vaccine was personalized to each patient with a goal of getting the most out of their unique immune system.