A Study of a Patient-Specific Neoantigen Vaccine in Combination With Immune Checkpoint Blockade for Patients With Metastatic Colorectal Cancer
The primary objective of the Phase 2 portion of the study is to characterize the clinical activity of maintenance therapy with GRT-C901/GRT-R902 (patient-specific vaccines) in combination with checkpoint inhibitors in addition to fluoropyrimidine/bevacizumab versus a fluoropyrimidine/bevacizumab alone as assessed by molecular response which is based on changes in circulating tumor (ct)DNA. The primary objective of the Phase 3 portion is to demonstrate clinical efficacy of the regimen as assessed by progression-free survival.
- Patients with histologically confirmed metastatic colorectal cancer (CRC) who are planned for, or have received <30 days of first-line treatment in the metastatic setting with FOLFOX/bev, CAPEOX/bev, FOLFOXIRI/bev, or CAPOXIRI/bev per SOC
- Measurable and unresectable metastatic disease according to RECIST v1.1
- Availability of formalin-fixed paraffin-embedded (FFPE) tumor specimens.
- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
- Patient has adequate organ function per defined criteria
- If women of childbearing potential (WCBP), must be willing to undergo pregnancy testing and agrees to the use at least 1 highly effective contraceptive method during the study treatment period and for 150 days after last investigational study treatment.
- Patients with deficient mismatch repair (dMMR) or microsatellite instability (MSI-H) phenotype
- Patient has a known tumor mutation burden <1 non-synonymous mutations/megabase
- Known DNA Polymerase Epsilon mutations
- Patients with known BRAFV600E mutations
- Bleeding disorder or history of significant bruising or bleeding following IM injections or blood draws
- Immunosuppression anticipated at time of study treatment
- History of allogeneic tissue/solid organ transplant
- Active or history of autoimmune disease or immune deficiency
- Patient with symptomatic or actively progressing central nervous system (CNS) metastases, carcinomatous meningitis, or has been treated with whole brain radiation
- History of other cancer within 2 years with the exception of neoplasm that has undergone potentially curative therapy
- Any severe concurrent non-cancer disease that, in the judgment of the Investigator, would make the patient inappropriate for the current study
- Active tuberculosis or recent (<2 weeks) clinically significant infection, evidence of active hepatitis B or hepatitis C, or known history of positive test for HIV
- History of pneumonitis requiring systemic steroids for treatment (with the exception of prior resolved in-field radiation pneumonitis)
- Myocardial infarction within previous 3 months, unstable angina, serious uncontrolled cardiac arrhythmia, history of myocarditis, or congestive heart failure (Class III or IV).
- Pregnant, planning to become pregnant, or nursing.