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  • Researchers are investigating a potential vaccine that could help prevent certain cancers from returning.
  • The vaccine, labeled the ELI-002 vaccine, appeared to reduce the risk of relapse in some people with pancreatic and colorectal cancers.
  • All of the patients had a specific tumor mutation called mKRAS mutation, which is one of the more common gene mutations linked to cancer.

Scientists have developed a vaccine that could potentially help prevent some types of pancreatic and colorectal cancers from recurring.

The shot was put to the test in a Phase I trial led by researchers at The University of Texas MD Anderson Cancer Center.

The vaccine, labeled the ELI-002 vaccine, appeared to reduce the risk of relapse in people with pancreatic and colorectal cancers who’d previously had surgery and chemotherapy, according to the study, which published Tuesday in Nature Medicine.

People who’ve undergone surgery for pancreatic and colorectal cancer have a high risk of relapsing.

Having an effective vaccine that can attack any remaining cancer cells in the body could lower the risk of relapse and, ultimately, boost chances of survival.

“These findings are very exciting because this is one of the first studies to show that a vaccine may reduce the chance of a very aggressive cancer (pancreas) from returning,” said Dr. Anton Bilchik, MD, PhD, a surgical oncologist and chief of medicine and director of the Gastrointestinal and Hepatobiliary Program at Saint John’s Cancer Institute in Santa Monica, CA.

Bilchik was not involved in the study.

The trial recruited 25 individuals with pancreatic or colorectal cancer who had previously had surgery, chemotherapy, and, in some cases, another procedure like radiation therapy.

All of the patients had a tumor mKRAS mutation, which is one of the more common gene mutations linked to cancer.

The patients received a maximum of 10 doses of the vaccine, which is specifically designed to target KRAS mutations, at various doses.

The researchers investigated how people’s immune system’s produced T cell responses after receiving the vaccine.

“T cells are an essential component of the immune system that have a profound impact on how cells function and also build a defense against diseases like cancer from occurring or relapsing,” Bilchik explained.

The team found that 84% of all patients developed a T cell response and 100% of patients who received the two highest vaccine doses developed a T cell response.

T cell responses were linked to reductions in tumor biomarkers and clearance of ctDNA, which is a type of DNA that comes from cancerous cells and tumors.

In addition, the T cell responses produced by the vaccine were associated with an 86% reduced risk of relapse or death.

The most common side effects included fatigue, injection site reaction, and muscle aches and pains.

The findings are early and preliminary but this type of vaccine could transform the future of cancer care, says Dr. Daniel Landau, an oncologist and hematologist with the Medical University of South Carolina and contributor for The Mesothelioma Center.

Landau did not work on the new study.

“Having a positive finding in a vaccine that could target pancreatic cancer cells would be a huge advancement for the field of oncology in general,” Landau said.

Even after pancreatic or colorectal cancer has been surgically removed and there are no traces of cancer in the body, the risk of relapse is high, explained Dr. Christopher Chen, an oncologist and hematologist with Stanford Medicine.

“Microscopic cancer cells may have already escaped the cancer before the surgery that cannot be detected in imaging tests,” Chen, who did not work on the new study, explained.

Relapsed cancer is often incurable.

Having an effective shot that can ignite a T cell response — which plays an important role in the immune system’s fight against cancer cells — can help the body do the work that chemotherapy currently does, Landau said.

“We have been spending decades trying to find ways to move away from traditional chemotherapies — which we compare to dropping a bomb — and, instead, find ways to utilize the body’s immune system to target and destroy the cancers for us,” Landau said.

Scientists have been working on developing a vaccine that stimulates the immune system’s T cells to destroy cancer cells, however, few have shown robust results.

“The possibility that recurrence risk could be reduced further with a low-risk vaccine could be a major step forward towards increasing cure rates for this patient population,” Chen said.

The shot is “off the shelf,” meaning it doesn’t have to be tweaked for each person.

“Off the shelf is beneficial because it can be produced in large quantities quickly, is less expensive and can potentially target many different types of cancer,” says Bilchik.

Though these preliminary findings are promising, more data is needed to understand the shot’s efficacy.

Due to the successes observed in the Phase 1 trial, a Phase II trial is slated to begin later this year.

“If these results can be confirmed via a larger study, this could represent a major advance for patients with resectable pancreatic and colorectal cancer,” Chen said.

Scientists have developed a vaccine that may prevent some types of pancreatic and colorectal cancers from recurring. People who’ve undergone surgery and chemotherapy for pancreatic and colorectal cancer have a high risk of relapsing. A vaccine could teach the immune system to attack remaining cancer cells, thereby lowering the risk of relapse and boosting survival rates.