Phase 1/2 Study of EO4010 with Nivolumab and/or Bevacizumab in Previously Treated Metastatic Colorectal Carcinoma

The primary objective of this clinical trial is to evaluate the **safety** and tolerability of EO4010, a novel microbial-derived peptide therapeutic vaccine, in combination with nivolumab and/or bevacizumab in patients with unresectable, previously treated locally advanced or metastatic colorectal carcinoma (mCRC). This is clinically relevant as it aims to determine the potential of EO4010 to be safely integrated into existing treatment regimens for mCRC, potentially offering a new therapeutic option for patients with limited treatment alternatives.

The secondary objectives include:

• Assessment of immunogenicity in relation to T cells of each peptide composing EO4010.
• Evaluation of T cell cross-reactivity with human tumor-associated antigens (TAAs).
• Measurement of objective response rate (ORR) and disease control rate (DCR).
• Determination of time to response (TTR) and duration of response (DOR).
• Analysis of progression-free survival (PFS) and PFS rate at 4 months.
• Assessment of overall survival (OS).

The clinical trial involves a total of **14 participants** diagnosed with unresectable, previously treated locally advanced or metastatic **colorectal carcinoma**. The study population includes both male and female subjects, aged 18 years and older, with an **ECOG performance status** of 0 to 1, indicating they are fully active or restricted in physically strenuous activity but ambulatory. Participants were selected based on their HLA-A2 positive status and the presence of advanced non-resectable colorectal adenocarcinoma that is mismatch repair proficient and microsatellite stable. They have either been previously treated with or are not considered candidates for therapies including fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapies, anti-VEGF agents, and anti-EGFR agents. The trial population is characterized by progression during or within three months following the latest administration of standard therapies. Both genders are represented, and the study includes a vulnerable population. Lifestyle considerations such as diet, physical activity, or habits are not specified in the available data.

The clinical trial is designed as a **randomized**, **double-blind**, and **controlled** study to evaluate the safety and tolerability of EO4010, a novel microbial-derived peptide therapeutic vaccine, in combination with **nivolumab** and/or **bevacizumab**. The trial targets patients with unresectable, previously treated locally advanced or metastatic colorectal carcinoma. The primary objective is to assess the safety profile of EO4010 in combination with the other agents, focusing on the incidence of adverse events, treatment-emergent adverse events, serious adverse events, and laboratory abnormalities, as per the NCI-CTCAE v5.0 grading system. Secondary endpoints include the evaluation of immunogenicity, overall response rate, disease control rate, time to response, duration of response, progression-free survival, and overall survival.

The trial is expected to last until September 2026, with recruitment having commenced in March 2023. Participants will be involved in the study for the duration of the trial, with specific conditions outlined for early termination, such as significant adverse events or withdrawal of consent. The sequence of study visits includes an initial screening visit to confirm eligibility based on criteria such as HLA-A2 positivity, ECOG performance status, and previous treatment history. Follow-up visits will be scheduled to monitor safety, efficacy, and immunogenicity, with assessments conducted through clinical evaluations and laboratory tests. The end-of-study visit will conclude the participant's involvement, ensuring all safety and efficacy data are collected and analyzed.

Inclusion criteria require participants to be at least 18 years old, with a performance status of 0 to 1, and having progressed during or within three months following the latest administration of standard therapies. The trial excludes individuals who do not meet these criteria or who have conditions that may interfere with the study's objectives. The investigational products, including EO4010, are administered via subcutaneous injection, while nivolumab and bevacizumab are delivered through intravenous infusion. The trial's design ensures rigorous monitoring and data collection to achieve its primary and secondary objectives, contributing valuable insights into the treatment of metastatic colorectal carcinoma.

The clinical trial involves the administration of **OPDIVO**, a concentrate for solution for infusion, containing the active substance **nivolumab**. This pharmaceutical form is intended for **intravenous** administration. The concentration of the solution is 10 mg/mL. The product is manufactured by Bristol-Myers Squibb Pharma EEIG and is relabeled for clinical trial purposes in accordance with GMP Annex 13 requirements. The administration schedule and dosage are determined based on the trial protocol, and participant compliance is monitored throughout the study.

Another experimental treatment in the trial is **EO4010**, an emulsion for injection, which includes a combination of active substances: **UCP2, EO2317, EO2318, OMP10, OMP12,** and **OMP11**. This product is administered via **subcutaneous injection**. The manufacturer, Enterome, has developed this structurally diverse substance as a vaccine. The dosing schedule and administration frequency are specified in the trial protocol, with adherence monitored to ensure participant compliance.

The trial also includes **Zirabev**, a concentrate for solution for infusion, containing the active substance **bevacizumab**. This product is administered through **intravenous use**. The concentration of the solution is 25 mg/mL, and it is produced by Pfizer Europe MA EEIG. Similar to OPDIVO, Zirabev is relabeled for clinical trial purposes in compliance with GMP Annex 13. The administration and dosing schedules are outlined in the study protocol, with compliance monitoring in place.

In this trial, no placebo or standard-of-care therapy is used as a comparator. The primary objective is to evaluate the safety and tolerability of EO4010 in combination with nivolumab and/or bevacizumab in patients with previously treated metastatic colorectal carcinoma. The trial protocol provides detailed instructions on the administration, dosing, and monitoring procedures to ensure the integrity and reliability of the study outcomes.

The efficacy of the clinical trial will be assessed through a series of primary and secondary endpoints. The primary endpoint focuses on the safety and tolerability of EO4010 in combination with **nivolumab** and/or **bevacizumab**. This will be evaluated by a descriptive medical assessment of the combined profile of incidences of adverse events (AEs), treatment-emergent AEs (TEAEs), serious AEs (SAEs), deaths, reasons for treatment discontinuation or delays, and laboratory abnormalities. The assessment will utilize the NCI-CTCAE v5.0 grading system.

Secondary endpoints include the percentage of patients demonstrating immunogenicity, which is determined by the expansion of specific T cells. This will be assessed by comparing samples taken at baseline versus on treatment using interferon-gamma (IFN-γ) enzyme-linked immunospot (ELISpot), intracellular cytokines staining, or multimers staining assays. Additional secondary endpoints include cross-reactivities with human tumor-associated antigens (TAAs), overall response rate (ORR), disease control rate (DCR), time to response (TTR), duration of response (DOR), progression-free survival (PFS) as described by RECIST 1.1 and iRECIST criteria, and overall survival (OS).