NCT06225011 · Jonsson Comprehensive Cancer Center
Fluoxetine for the Modification of Colorectal Tumor Immune Cells Before Surgery in Patients With Colorectal Cancer
What this study is about
This phase I trial tests whether fluoxetine (prozac) works to modify the tumor immune cells before surgery in patients with colorectal cancer. Fluoxetine is a commonly used selective serotonin reuptake inhibitor (SSRI) prescribed for major depressive disorder and generalized anxiety.
View original scientific description
This phase I trial tests whether fluoxetine (prozac) works to modify the tumor immune cells before surgery in patients with colorectal cancer. Fluoxetine is a commonly used selective serotonin reuptake inhibitor (SSRI) prescribed for major depressive disorder and generalized anxiety. Giving fluoxetine may modify the immune cell composition in the tumor and its microenvironment and may induce changes in body's immune system and may interfere with the ability of tumor cells to grow and spread in patients with colorectal cancer.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Male or female ≥ 18 years of age at visit 1
- Previously untreated cytologically or histologically confirmed colorectal adenocarcinoma that will not need neoadjuvant therapy
- Written informed consent (and assent when applicable) obtained from subject or subject's legal representative and ability for subject to comply with the requirements of the study
- World Health Organization (WHO) Eastern Cooperative Oncology Group (ECOG) performance status 0-2
- Absolute neutrophil count (ANC) ≥ 1.5x10\^9/L
- Platelets ≥ 100x10\^9/L
- Hemoglobin ≥ 9 g/dL
- Serum creatinine (sCr) ≤ 1.5 x upper limit of normal (ULN)
- Creatinine clearance (Ccr) ≥ 40 mL/min (as calculated by Modified Cockcroft-Gault formula)
- Serum total bilirubin ≤ 1.5 x ULN
- Aspartate aminotransferase (AST)(serum glutamic-oxaloacetic transaminase \[SGOT\]) / alanine aminotransferase (ALT)(serum glutamate pyruvate transaminase \[SGPT\]) ≤ 2.5 x ULN
- Baseline corrected QT (QTc) within normal limits per the Bazett formula. Any electrocardiogram (EKG) done prior to consent is acceptable for baseline QTc monitoring.
- Normal QTc ranges from 350-450 ms for adult men and from 360-460 ms for adult women
Exclusion criteria
- Presence of a condition or abnormality that in the opinion of the investigator would compromise the safety of the participant or the quality of the data
- A diagnosis of metastatic colorectal adenocarcinoma
- Individuals who have received neoadjuvant chemotherapy prior to the planned colon cancer resection
- Individuals with absolute or relative contraindications to fluoxetine
- Baseline prolonged QTc
- Concurrently taking tamoxifen, pimozide, or thioridazine
- Individuals using other SSRIs, serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), lithium or other antidepressants at time of initial biopsy
- Currently active second primary malignancy or history of malignancy less than 5 years prior to the time of study eligibility (Patients with history of skin cancers excluding melanoma will be eligible for participation)
Where
- Los Angeles, California
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 11, 2026 · Source of record for eligibility and locations