Recruiting
Phase 1

Fluoxetine

Sponsor:

Jonsson Comprehensive Cancer Center

Code:

NCT06225011

Conditions

Colorectal Adenocarcinoma

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

Fluoxetine

Study Details

Brief summary:

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.

Conditions

Colorectal Adenocarcinoma

Study ID

NCT06225011

Start date

Mar 20, 2025

Status verified date

Aug, 2026

Completion date

Jul 1, 2028

Anticipated

Primary completion date

Jul 1, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

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)

Study Design

Enrollment

10 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Treatment (fluoxetine)

Patients receive fluoxetine PO once QD for 10 days prior to surgery.

Interventions

Fluoxetine

Receive PO

Primary outcome measure

  • Immune cell composition and microenvironment [ Time Frame: within a year of surgery ]

Central Contacts and Locations

Central contacts

Jasmine Mitchell, MD

310-825-0712jlmitchell@mednet.ucla.edu

Locations

UCLA / Jonsson Comprehensive Cancer Center

Recruiting

Los Angeles, California, United States, 90095

Contacts

Jasmine Mitchell, MD

310-825-0712jlmitchell@mednet.ucla.edu

Principal Investigator:

Jasmine Mitchell, MD

More Information

Sponsor

Jonsson Comprehensive Cancer Center

Last update posted

Aug 20, 2026

Last verified

Aug, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Jonsson Comprehensive Cancer Center on 2026-08-20.