This study is for patients with a diagnosis of colorectal adenocarcinoma that is unresectable or metastatic.

Key Elgibility Criteria

You may be eligible for this study if you meet the following conditions:

• Are at least 18 years old
• Have had disease progression or were intolerant to other treatment protocols
• Has at least 1 measurable tumor of ≥1 cm in longest diameter (or ≥1.5 cm shortest diameter for lymph nodes)
• Have not received more than 3 lines of prior treatment
• Capable of giving signed informed consent which includes willingness to comply with the requirements and restrictions listed in the informed consent form
• Have no known acute or chronic hepatitis B or known acute or chronic hepatitis C virus
• Have no active significant herpetic infections or prior complications of HSV-1 infection
• Have no active or history of central nervous system (CNS) metastases and/or carcinomatous meningitis.
• Prior organ transplantation including allogenic stem-cell transplantation

What to expect during the study

The study will consist of the following two treatment groups:

• RP2 in combination with atezolizumab and bevacizumab
• RP3 in combination with atezolizumab and bevacizumab

Patients will receive four doses of RP2 or RP3 once every 2 weeks at a lower concentration. This will be followed by three doses at a higher concentration. This same concentration will then be given once every 3 weeks for a total of up to 8 doses.

Additional courses of RP2 or RP3 may be possible based on eligibility.

The study has different sections. They are:

Screening	Up to 28 days
Treatment Period	Up to 3 years
Follow-up Period	Up to 3 years

IMPORTANT: Only your doctor can determine whether or not you are eligible to participate in this clinical study. Please note that if you decide to participate in the study, you can also choose to stop at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.