Background
- Colorectal cancer (CRC) is the fourth most common cancer diagnosis in the United States
and accounts for the second most cancer-related deaths.
- Programmed death ligand 1 (PD-L1) is a transmembrane protein that was first identified
for its role in the maintenance of self-tolerance and prevention of autoimmunity.
Blockade of the interaction between PD-L1 on tumor cells and PD-1 on T cells is expected
to reverse T cell suppression within tumors. These agents are dependent on underlying T
cell activation against the tumor cell to be effective.
- Avelumab is a fully human immunoglobulin G 1 (IgG1) anti-PDL1 antibody that selectively
binds to PD-L1 and competitively blocks its interaction with PD-1.
- In ongoing phase 1 trials of avelumab, the agent has been well tolerated and has shown
clinical activity.
- Clinical trials with anti-PD-1/L1 agents in colorectal cancer have resulted in minimal
activity in patients who do not have mismatch repair deficiency (MMR-D).
- Therapeutic cancer vaccines targeting overexpressed proteins offer a potential method to
activate T cells against tumors.
- A novel adenovirus-based, carcinoembryonic antigen (CEA)-targeting vaccine has
demonstrated cytolytic T cell responses in patients with metastatic colorectal cancer.
- Standard of care agents in first line metastatic colorectal cancer (CRC) have properties
been associated with improved immune response via immunologic cell death and immunogenic
modulation.
Primary Objective
-To determine if there is an improvement progression free survival among patients with
metastatic colorectal cancer lacking a mismatch repair deficiency who are treated with
standard of care + anti- PDL1 monoclonal antibody + Ad-CEA therapeutic cancer vaccine
compared with standard of care alone.
Eligibility
- Subject's age 18 and older with previously untreated pathologically confirmed metastatic
or unresectable colorectal cancer; prior adjuvant therapy is acceptable.
- Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 2.
- Normal organ and bone marrow function.
- Subjects with active autoimmune diseases requiring treatment and subjects requiring
system steroids (except for physiologic doses for steroid replacement) are not allowed.
- Tumor sample and whole blood sample must be available for proteomics, genomics and
transcriptomics analyses.
- Subjects with metastatic or unresectable colorectal cancer with mismatch repair
deficiency (MMR-D or microsatellite instability (MSI)-High) will not be eligible.
Design
- This is a randomized, multicenter phase II clinical trial designed to evaluate the
potential improvement in progression free survival (PFS) when Avelumab and Ad-CEA
vaccine are used in combination with standard of care therapy in metastatic or
unresectable colorectal cancer when compared with standard of care alone (FOLFOX-A).
- A lead in cohort, comprising the first 6 evaluable subjects enrolled, will be treated
with avelumab + Ad- CEA vaccine + standard of care in order to assess the safety of the
combination.
- If no more than 1 subject in the lead in cohort experiences a dose limiting toxicity
attributable to the investigational new drug (IND) agents, 70 evaluable subjects will be
randomized on a 1:1 basis to receive either Avelumab + Ad-CEA vaccine + standard of care
(Arm B) or standard of care alone (Arm A).
- Standard of care therapy consists of 6 - 12 two-week cycles of bevacizumab + FOLFOX
(5-FU, leucovorin, oxaliplatin) followed by two-week cycles of bevacizumab +
capecitabine until disease progression.
- Subjects assigned to Arm A that have progressive disease will be offered Avelumab +
Ad-CEA vaccine in combination with a standard chemotherapy regimen.
- Kaplan-Meier curves and a two-tailed log-rank test will be the primary analysis methods.
- The accrual ceiling for the study is set at 97.