Elicio's Cancer Vaccine Trains Immune System to Broaden Attack

BOSTON, MA – December 11, 2025 – In a significant development for cancer immunotherapy, Elicio Therapeutics (Nasdaq: ELTX) has announced promising new data suggesting its "off-the-shelf" vaccine, ELI-002 7P, can provoke a broader, more personalized immune attack against tumors than previously understood. The findings, from a subset of patients in the ongoing Phase 2 AMPLIFY-7P trial, show the therapy not only hits its intended targets but also trains the body's T cells to hunt down other unique cancer antigens, a powerful phenomenon known as "antigen spreading."

This ability to generate a multi-pronged attack could be a critical step toward creating more durable remissions and preventing relapse in patients with notoriously difficult-to-treat cancers driven by KRAS mutations, such as pancreatic and colorectal cancer. The results suggest Elicio may be bridging the gap between highly individualized cancer treatments and scalable, readily available therapies.

Beyond the Initial Target: The Power of Antigen Spreading

At the core of today's announcement is the concept of antigen spreading. Elicio's ELI-002 7P is designed to target seven of the most common mutations in the KRAS gene, a driver in roughly a quarter of all solid tumors. The latest analysis, however, reveals a more profound effect. In a cohort of 15 patients from the Phase 2 trial, a remarkable 87% (13 patients) demonstrated a significant expansion of T cells that recognized and targeted other patient-specific tumor neoantigens—mutations unique to an individual's cancer that were not included in the vaccine itself.

The magnitude of this secondary response was substantial, with a median 10.6-fold increase in these neoantigen-specific T cells over baseline. Furthermore, 90% of these responses involved both CD4+ "helper" and CD8+ "killer" T cells, indicating a comprehensive and robust immune mobilization. This process, where the immune system's attack broadens from the initial vaccine targets to a wider array of tumor markers, is considered a key mechanism for overcoming cancer's ability to evolve and evade treatment. By creating a more diverse and adaptable anti-tumor response, the therapy may prevent cancer cells from escaping immune surveillance, a common cause of relapse.

These findings build upon a strong foundation of immunogenicity data. Across a larger group of 90 evaluable patients in the Phase 2 study, 99% mounted a potent T cell response against the mKRAS targets included in the vaccine. The consistency of these results with earlier Phase 1 observations strengthens the case that ELI-002 7P is reliably activating the immune system in a powerful and therapeutically meaningful way.

"We are extremely pleased to observe induction of personalized neoantigen-specific T cell responses in a significant majority of assessed Phase 2 patients," said Robert Connelly, Chief Executive Officer of Elicio, in a statement. He noted that these findings suggest ELI-002 7P "has the potential to generate broad tumor-specific immunity targeting both driver mKRAS antigens and personalized neoantigens," which could lead to "more personalized and durable clinical responses."

An 'Off-the-Shelf' Vaccine with a Personalized Punch

Perhaps the most significant implication of Elicio's data is that it achieves this personalized immune response with an "off-the-shelf" product. This stands in stark contrast to the first generation of personalized cancer immunotherapies, which require a complex and expensive process of sequencing a patient's tumor, identifying unique neoantigens, and manufacturing a custom vaccine for that individual alone. While scientifically elegant, this approach faces major logistical and financial hurdles to widespread adoption.

Elicio's strategy circumvents these challenges. ELI-002 7P is a pre-manufactured therapy designed to be readily available for a large patient population. Its ability to subsequently induce a patient-specific response via antigen spreading offers the best of both worlds: the scalability of a conventional drug and the precision of a personalized one.

This is made possible by the company's proprietary Amphiphile (AMP) platform. The technology is designed to deliver the vaccine components—the KRAS antigens and a powerful immune-stimulating adjuvant—directly to the lymph nodes. By targeting this "brain center" of the immune system, the AMP platform aims to provide a more efficient and powerful education for T cells. The platform works by latching the therapeutic payload onto albumin, a common protein in the body, which then naturally traffics to the lymph nodes, concentrating the immunotherapy where it can be most effective. This targeted delivery is believed to be crucial for generating the high-magnitude T cell responses and subsequent antigen spreading observed in the trials.

A New Strategy Against a Formidable Foe: mKRAS Cancers

The clinical need for such an advancement is immense. KRAS mutations are notorious drivers of some of the most aggressive and lethal cancers. In pancreatic ductal adenocarcinoma (PDAC), for example, KRAS mutations are found in over 90% of cases. The prognosis for these patients is grim, and recurrence rates are devastatingly high, even after surgery and chemotherapy.

ELI-002 is being studied in this exact high-risk setting—in patients who have completed initial therapy but still have a high probability of relapse, often identified by the presence of minimal residual disease (MRD). This is a critical window where patients are typically relegated to a "watch and wait" approach. A therapy that can actively train the immune system to seek and destroy lingering cancer cells during this period could fundamentally change the standard of care and improve survival outcomes.

The competitive landscape for KRAS-targeted therapies is intense, but Elicio's approach occupies a unique position. While small molecule inhibitors like Amgen's sotorasib have marked a major step forward, they typically target only a single KRAS mutation (G12C) and can be susceptible to drug resistance. ELI-002 7P, by contrast, provides coverage against seven different KRAS mutations, broadening its applicability. More importantly, the induction of antigen spreading provides a built-in defense against tumor evolution and resistance, a key potential advantage over single-target agents.

From Lab Data to Market Disruption: Elicio's Strategic Position

Investors have taken note of the program's accumulating positive data. Elicio's stock (ELTX) has shown significant positive momentum over the past year, with analyst reports pointing to the disruptive potential of its platform. The latest data on antigen spreading adds another layer of validation to the company's scientific and commercial strategy.

The clinical pathway is also becoming clearer. The U.S. Food and Drug Administration (FDA) has provided positive feedback on a potential registrational Phase 3 trial design, aligning with Elicio on key parameters like the target patient population and the primary endpoint of disease-free survival. This regulatory clarity significantly de-risks the path forward and provides a tangible goal for the company and its investors.

By combining a scalable, off-the-shelf manufacturing process with a technology that elicits a powerful, personalized, and durable immune response, Elicio is positioning ELI-002 not just as another cancer drug, but as a potential paradigm shift. If the robust T-cell responses and broad antigen spreading seen in these early analyses translate into a meaningful improvement in relapse prevention and overall survival in the randomized Phase 2 and future Phase 3 trials, Elicio could redefine the treatment landscape for a vast population of cancer patients.