Evaluation of RBS2418 in Patients With Advanced, Metastatic, and Progressive Colorectal Cancer

Inclusion Criteria: 1. At least 18 years of age on the day of signing informed consent. 2. Male and female subjects with advanced, metastatic, progressive CRC who have received, been ineligible for, intolerant to, or declined all approved standard of care (SOC) therapies for metastatic CRC, as per local SOC treatment regimens. Additionally, subjects must have documented PD based on two scans performed within 2 to 4 months of study initiation. 3. Have histologically or cytologically confirmed CRC diagnosis based on pathology report. 4. Willing to submit a pre-treatment tissue sample (archival, or fresh tissue if archival is not available). Exclusion Criteria: 1. Any approved anti-cancer therapy including chemotherapy, targeted small molecule therapy, systemic immunotherapy, or radiation therapy within 2 weeks prior to the first dose of study treatment; or if subject has not recovered (i.e., ≤ to Grade 1 or returned to baseline level) from AEs due to a previously administered agent; the following exceptions are allowed: * Palliative radiotherapy for bone metastases or soft tissue lesions should be completed \>7 days prior to the first dose of study treatment. * Hormone-replacement therapy or oral contraceptives. * Subjects with Grade 2 neuropathy or Grade 2 alopecia. 2. Subjects with evidence of rapid progression on prior therapy resulting in rapid clinical deterioration. 3. Malignancies other than indications open for enrollment within 3 years prior to Day 1, except for those with negligible risk of metastasis or death treated with expected curative outcome, undergoing active surveillance, or treatment-naïve for indolent tumors.