Prospective, open label, multi-dose, sequential dose escalation, single-center, Phase 1 trial

This is a single center, open-label, phase 1 study to evaluate the safety and tolerability of GB104 and explore gut microbial composition in patients with colorectal cancer who completed standard treatment including curative colectomy with or without full-cycle adjuvant chemotherapy. GB104 is a live biotherapeutic product consisting of a lyophilized formulation of a single strain of bacterium. The dosing regimen for the study involves the oral administration of the experimental drug once a day.

Inclusion Criteria:

1. Subjects who sign on an informed consent form willingly

2. Subjects who have histological and radiological diagnosis of colorectal cancer

3. Males and females aged between 19 and 80 years at the time of screening

4. Subjects who have undergone radical colectomy and received the following treatments before participating in the clinical trial, and have completed the specified period:

   • Subjects who have received adjuvant chemotherapy, radiotherapy, or concurrent chemoradiotherapy and have completed 3 months since the last treatments
   • Subjects who have not received any adjuvant therapy and have completed 3 months from the radical colectomy
   • Subjects who have undergone stoma closure and have completed 3 months after stoma closure

5. Subjects who have received standard treatment for colorectal cancer without disease progression or recurrence until the first administration of GB104

6. Subjects who have received adjuvant chemotherapy or radiation therapy, and have completed 3 months after completing the treatment, and toxicity from previous adjuvant treatment must have recovered to NCI-CTCAE v5.0 grade 1

7. Subjects who have been confirmed to have adequate hematological, renal, and hepatic function at the screening point (laboratory tests may be retested during the screening period)

8. Female subjects of childbearing potential and sexually active men who agree to abstain from sexual activity or use an adequate method of contraception

Exclusion Criteria:

1. Significant cardiac dysfunction, New York Heart Association classification for chronic heart failure III-IV, symptomatic coronary artery disease, significant deep vein thrombosis; myocardial infarction within 6 months
2. Severe active infections that require systemic antibiotics, antifungal agents, antiviral agents, or other medications that cannot be controlled
3. Previous history of immunosuppressant within the 1 month of initial administration
4. Known HIV infection, or active infection with hepatitis B or C
5. Subjects who have completed a course of antibiotics within the one month prior to screening