Off-the-shelf cancer vaccine shows promising results in patients with KRAS-mutated tumors

Samara Rahman, 74, considers herself lucky. 

She gets to take walks on the beach, go swimming and ride her bike -; all things that were taken from her when she was diagnosed with pancreatic cancer in November of 2022. 

Pancreatic cancer is the third leading cause of cancer-related deaths in the United States and is one of the most difficult cancers to treat since it's often diagnosed at advanced stages and can spread quickly to other parts of the body.

For Rahman, it all started when the bicoastal resident, who splits her time between Baltimore and Los Angeles, was hit with a prolonged bout of stomach troubles that resulted in weeks of diarrhea.

When she went to the doctor, she was told to just take some over-the-counter medication to help alleviate and manage her symptoms. But she knew this was a much bigger issue.

"I knew it was something more and I wanted to know what was wrong with me," said Rahman. "So, I saw my doctor and took some additional tests, including an MRI, which showed that I had pancreatic cancer."

Just weeks after her diagnosis, Rahman had surgery, followed by chemotherapy. The chemo treatment, however, was too taxing for her body to endure.

Rahman and her family -; which includes her husband, son and daughter -; knew they needed to find another treatment to help keep the cancer at bay, given that pancreatic cancer is known to be highly resistant to treatments.

Even after having surgery and completing chemotherapy for pancreatic cancer, some patients still face the risk of the disease coming back.

The AMPLIFY-201 trial

Rahman and her family ended up at UCLA Health to learn more about a clinical trial that was evaluating an experimental "off-the-shelf" vaccine that is given after surgery to prevent or delay the cancer from coming back in high-risk patients. 

Unlike some other cancer treatments that may need to be personalized for each patient based on their specific characteristics and mutations, an "off-the-shelf" vaccine is designed to be a standardized product that can stimulate the immune system to recognize and attack cancer cells in a general way, without the need for the time-consuming and complex process of creating a unique vaccine for each patient.

This approach can bring immunotherapies to more patients in a timelier manner, which is one of the major barriers in getting these life-saving treatments to patients. 

Zev Wainberg, MD, professor of medicine at the David Geffen School of Medicine at UCLA and researcher in the UCLA Health Jonsson Comprehensive Cancer Center, was one of the investigators on the phase 1 clinical trial.

In this study, Dr. Wainberg and other researchers used a lymph node-directed vaccination, called ELI-002 2P, that targets KRAS mutations. These mutations are present in 25% of solid tumors and drive about 90% of pancreatic cancers and 50% of colorectal cancers.

The vaccine contains synthesized peptides, which act like a signal to tell the immune system to go after and destroy cancer cells carrying two of the KRAS mutations, G12R and G12D, the most commonly occurring variants in pancreatic, colorectal, non-small cell lung, ovarian, biliary and gallbladder cancers.

This approach has the potential to boost the body's own mKRAS-targeting immune cells in a wide variety of people. It's designed to be easy to produce, and once made, it can be readily available for use without the need for complex customization. I was especially eager to enroll Samera in this study since she had a very difficult time on chemotherapy and had high-risk disease." 

Dr. Zev Wainberg, MD, professor of medicine, David Geffen School of Medicine at UCLA

Once Rahman was cleared as a candidate for the trial, she had no hesitation in enrolling in the study.

She began treatment in August 2023 and finished receiving her boosters in February of 2024. She'll remain in the observation part of the study.

Currently, Rahman has no signs of the disease. And she is not the only one who has had an encouraging outcome.

Promising results

The results of the first phase of the study, published in Nature Medicine in January 2024, showed the vaccine significantly decreased tumor biomarkers, produced strong T-cell responses leading to a reduced risk of relapse and death among patients and was overall deemed safe.

The trial, supported by Elicio Therapeutics, included 25 patients (20 pancreatic, five colorectal) with mKRAS-driven cancers with minimal residual disease following surgery to remove the tumor.

Each cohort received escalating doses of ELI-002 to determine safety and tolerability and to assess preliminary antitumor activity.

The researchers found the vaccine induced specific immune responses in 84% of patients and tumor biomarker responses were observed also in 84% of patients. In 24% of patients, the biomarkers associated with the tumor were completely absent.

And maybe even most significant, patients with higher T-cell responses had a longer relapse-free survival -; time without the disease returning -; compared to those with lower T-cell responses. The median relapse-free survival was 16.33 months.

"Overall, this study shows promising results in patients with KRAS-mutated tumors that are typically challenging to treat with immunotherapy," said Wainberg, who is an author on the study. "There haven't been any vaccines developed to prevent a cancer recurrence in pancreatic cancer, and if proven, this would be an important advance."

What's next: Phase 2 Trial and Hawaii

To validate these preliminary findings, a phase 2 clinical trial recently opened that will include a larger number of patients and greater diversity to assess the general applicability of the vaccine. The vaccine for this phase also targets seven KRAS mutations, instead of just two.

And for Rahman, a semi-retired real estate broker, she is busy planning her next big trip to Hawaii.

"I'm doing everything that I did before my diagnosis," said Rahman. "I can do anything that I want. I can walk long distances; I can swim and I can ride my bike again."