Pancreatic cancer is incredibly difficult to shake.
Even after surgery or chemotherapy, the disease may never completely go away.
By some estimates, pancreatic malignancies may recur in up to 80% of patients.
People with certain genetic mutations appear to be particularly at risk of disease recurrence.
A new clinical trial, led by a Mayo Clinic researcher, has tested a potential vaccine.
In a randomized phase 2 trial, almost all patients who received this vaccine developed an immune response against a mutated gene called KRAS.
KRAS mutations are found in approximately 90% of pancreatic ductal adenocarcinomas, which are the most common type of pancreatic cancer.
If a drug could target the cells that express these mutations, it could theoretically keep cancer at bay.
This doesn’t prove that this vaccine can prevent pancreatic cancer from recurring, but they are encouraging signs, especially since other cancer vaccines have shown that similar immune responses are linked to better survival.
The results are published in Natural medicine.
“Historically, pancreatic cancer has been very difficult to treat with immunotherapy,” says first author and medical oncologist Ben George.
“What is encouraging is that we were able to generate a strong immune response against KRAS mutations in almost all patients we evaluated. In an exploratory analysis, patients with a greater immune response to the vaccine appeared protected with longer disease-free survival times.”
))>The new vaccine is called campuppimut and is designed to teach the body’s immune cells to recognize and attack cancer cells that express seven common mutations of the KRAS gene.
These mutations may help pancreatic cancer survive and grow.
The phase 2 trial included 144 patients treated for KRAS-mutated pancreatic cancer with surgery and chemotherapy.
At the start of the trial, none of these patients had visible signs of cancer on imaging tests.
George and his colleagues randomly assigned 96 of these patients to receive the vaccine, while another 48 served as controls.
Importantly, there was no statistically significant difference in disease-free survival between the two groups.
But those who received the vaccine showed a stronger immune response than before vaccination.
Of the 90 patients who received this drug and were able to be evaluated, 98.9 percent developed an increased T cell response against mutated KRAS.
In more than 80 percent of patients, the T cell response was more than nine times higher than before vaccination.
“We showed that we can teach the immune system to recognize these KRAS mutations,” says George.
“The next step is to determine whether this can change the course of the disease for patients.”
The results of the phase 2 trial provide proof of concept of the vaccine’s potential clinical benefit, the authors say.
The new drug targets the body’s lymph nodes, and so far it appears to reach these sites and successfully modify immune responses.
Beyond that, however, its benefits are unclear.
A planned Phase 3 trial will add additional booster shots of the vaccine to the list and possibly test how this drug works in combination with other cancer treatments.
Recently, for example, the first personalized mRNA cancer vaccine successfully completed a phase 3 clinical trial when combined with standard immunotherapy, according to results presented at a major cancer conference.
The two drugs combined reduced the risk of melanoma recurrence or death by 42 percent compared to standard treatment alone.
This melanoma vaccine also triggers an immune response, similar to the pancreatic vaccine. But the difference is that melanoma has shown clear clinical benefits.
Even if this pancreatic vaccine does not prolong survival, another is in preparation.
This drug, however, is a personalized mRNA vaccine, like the one against melanoma.
The vaccine is still in clinical trials, but as of this year, researchers said seven pancreatic cancer patients whose immune systems responded to the mRNA vaccine are alive and well.
One of the patients was diagnosed with fatal cancer at the age of 66 and received nine doses of the vaccine.
She is now 72 years old.
The future of cancer vaccines looks brighter than ever.
The research was published in Natural medicine.
This article was fact-checked by Rebecca Dyer and edited by Rebecca Dyer. Although we are proud of our process, we are only human. If you spot an error, please let us know.
Gn Health
