Vaccine demonstrates benefit in delaying cancer relapse

A lymph node-targeted cancer vaccine has shown potential to prevent relapse of KRAS-mutated pancreatic and colorectal cancers in patients who have had surgery, according to a Phase I trial led by US researchers.

The results were published in Nature Medicine. 

Results from the cancer vaccine clinical trial

In the trial, T cell responses were seen in 84 percent of all patients and in 100 percent of those in the two highest dose cohorts, including those who received the recommended Phase II dose of 10mg, the researchers found.  

The data showed that T cell responses were predictive of reductions in tumour biomarkers and circulating tumour DNA (ctDNA) clearance. This correlated with an 86 percent reduction in risk of relapse or death.

The AMPLIFY-201 clinical trial evaluating the off-the-shelf cancer vaccine ELI-002 was designed to lower the risk relapse by ‘training’ T cells to recognise KRAS mutations and therefore eliminate KRAS-mutant cells, the team noted.

Patients were given no more than 10 doses of the ELI-002 cancer vaccine targeted toward KRAS G12D and G12R mutations.

“It is early, but we saw some promising results that this vaccine may help many of these patients avoid relapse, which could increase survival,” principal investigator Dr Shubham Pant, Associate Professor of Gastrointestinal Medical Oncology, explained. “It also showed a favourable safety profile, which is exciting.” 

Further findings of patient T cell response

For those given the vaccine who were above the median T cell response level, median recurrence-free survival had not yet been reached. This is compared to 4.01 months in the group with a T cell response level below the median, which is a statistically significant improvement, according to the researchers. 

“Patients who have undergone surgery for pancreatic cancer are still at risk for relapse of the disease, even after they finish chemotherapy. This is especially true for patients who are positive for ctDNA, which puts them at a higher risk for relapse,” commented Dr Pant. “When these patients do relapse, the disease is not curable, so this is certainly an area of unmet need.”  

In the study, no patients were found to have dose-limiting toxicities, cytokine release syndrome (CRS) or any treatment-emergent adverse events of any kind above Grade 3.

A Phase II trial will commence later in 2024, utilising a new formulation of the ELI-002 cancer vaccine, targeting additional KRAS mutations.

The researchers highlighted that in 2023, preliminary data from the Phase I trial was presented at the American Society of Clinical Oncology (ASCO) Annual Meeting and at the American Association for Cancer Research (AACR) Special Conference on Pancreatic Cancer.  

This trial was supported by Elicio Therapeutics.