Cellular Aging and Neurobiology of Depression Study (CAN-D)

September 18, 2025 updated by: University of California, San Francisco

Neurosteroid Metabolism and the Antidepressant Effects of Serotonin Specific Reuptake Inhibitors (SSRI's)

We are conducting an eight week longitudinal study to learn if blood levels of certain naturally occurring compounds and genetic markers differ between patients with depression and healthy adults who are not depressed, and if any such differences relate to memory performance, mood, and neurobiology. We are also interested in how the gut microbiome is affected by antidepressant treatment.

We will do this by comparing the unmedicated depressed patients with matched healthy controls at baseline and then following the depressed patients over the course of eight weeks of standardized antidepressant treatment to gauge which baseline abnormalities normalize over the course of treatment.

Study Overview

Status

Completed

Detailed Description

Following an initial telephone screen to assess inclusion and exclusion criteria, the evaluation will continue with an in-person screening evaluation to assess the presence or absence of active medical history and history of major psychiatric illness, as well as review of the consent document. If found to be eligible, participants would then be admitted to the study.

The next step for eligible, consenting depressed subjects and is a baseline visit. The baseline visit will last up to 3.5 hours. We will begin the baseline visit by collecting a urine sample for a drug (and, for women, pregnancy) test. As long as that is negative, we will then collect a blood sample of about 180 cc. After the blood draw, participants will complete cognitive tests and meet again with the study psychiatrist. Eligible consenting healthy controls will come in for a one time study visit and complete the same tests performed during the depressed subject baseline visit. Both depressed participants and healthy controls will return a stool sample collected at home with a kit given during the screening visit.

After the baseline visit, depressed subjects (but not healthy controls) will begin taking an FDA approved antidepressant, as prescribed by the study psychiatrist, for the next 8 weeks while they are enrolled in the study. The specific drug will be decided upon between the participant and the study psychiatrist at the in-person screening visit.

After 4 weeks, depressed participants will return to UCSF to meet again with the psychiatrist to discuss symptoms and how to continue treatment. They will be given an at home collection kit to return a stool sample at the last study visit.

4 weeks later (after 8 weeks in total), depressed participants will come back for an additional visit that will include the same blood draw and testing as the baseline visit. They also will return their stool sample. A physician-investigator will meet with the depressed subjects to review their clinical responses to treatment and to make further treatment suggestions, which the subjects may use in discussions of their future treatment options with their personal physicians. If a decision is made to discontinue antidepressant treatment, the subjects will be given instructions on how to withdraw from the medication, and will be given up to a 4 week supply of the drug to facilitate this withdrawal.

Study Type

Interventional

Enrollment (Estimated)

228

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • San Francisco, California, United States, 94143-0984
        • University of California San Francisco

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

21 years to 60 years (Adult)

Accepts Healthy Volunteers

Yes

Description

All participants must meet the following criteria:

  • Age 21-60 and able to give informed consent.
  • Not "needle phobic," by self-report.
  • English-speaking (to allow accurate use of behavioral rating scales and verbal cognitive tests).
  • Females of child-bearing capacity must be non-pregnant (confirmed by urine pregnancy test) and using effective non-hormonal birth control (e.g. abstinence, condoms, IUD).
  • Good general medical health; no significant uncontrolled illnesses that will invalidate the designated outcome measures.
  • Clinical labs (electrolytes, liver function test, CBC) with no clinically significant abnormalities that result in medical treatment that will invalidate the designated outcome measures.
  • Negative urine toxicology (drugs of abuse) screen.
  • Taking no medication or drugs likely to interfere with the study objectives (including statins or medications that affect hormones [e.g. birth control pills or steroids]).
  • Free of all psychotropic medications (including antidepressants) for at least 6 weeks (with the exception of prn short-acting benzodiazepines or sedative-hypnotics, < 3 doses per week, and none for 5 drug half-lives before the study).
  • No vaccines for at least 4 weeks prior to baseline blood draw (including the flu shot).
  • Not currently anemic (Hct of 36-48 for females and 38-54 for males, or Hgb of 12.5-20) and has not donated blood for at least 8 weeks prior to baseline blood draw.
  • No neurological disorders and no history of concussion with a black-out that lasted > 10 minutes.
  • Willing to provide stool sample

Additional criteria for Depressed Participants:

  • Current DSM-5 diagnosis of Major Depressive Disorder, unipolar, with non-psychotic features.
  • Baseline 17-item Hamilton Depression Rating Scale (HDRS) rating of >= 17, or Baseline 25-item HDRS rating of >= 20.
  • Current depressive episode duration of > 6 weeks.
  • No current, active suicidal intent; HDRS "suicidality" item rating <= 2 OR by clinician determination.
  • No recent (< 6 month) history of substance or alcohol use disorder(s), with the exception of tobacco use (DSM-5 criteria).
  • No current (in the last month) diagnosis of Post-Traumatic Stress Disorder (DSM-5 criteria).
  • No anticipated changes in psychotherapeutic interventions during the course of the study.

Additional criteria for Normal Controls:

• No history of DSM-5 Axis I diagnoses

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Health Services Research
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Treatment with SSRI

Depressed participants will receive 8 weeks of treatment with one of the following serotonin-specific reuptake inhibitors:

fluoxetine (Prozac®), sertraline (Zoloft®), citalopram (Celexa®), escitalopram (Lexapro®)

The specific drug used for treatment will be selected by the study clinician based on clinical interviews and the participants preferences. Participants will be monitored for response and side effects by study clinician and will return after 8 weeks for a follow up study visit.

Participants who enroll in this phase are treated with an FDA-approved SSRI in an open-label "treatment-as-usual" manner, in accordance with clinical practices and at a titration rate no more rapid than the manufacturer's recommendations. The duration of the treatment phase is 8 weeks.

Other Name: fluoxetine (Prozac®), Sertraline (Zoloft®), citalopram (Celexa®), escitalopram (Lexapro®)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Depression ratings at baseline and Week 8
Time Frame: baseline and Week 8
baseline and Week 8
Serum levels of steroids and neurosteroids at baseline and Week 8
Time Frame: baseline and Week 8
baseline and Week 8

Secondary Outcome Measures

Outcome Measure
Time Frame
Serum levels of oxidative stress markers at baseline and Week 8
Time Frame: baseline and Week 8
baseline and Week 8
Serum levels of cytokines and immune markers at baseline and Week 8
Time Frame: baseline and Week 8
baseline and Week 8

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Owen Wolkowitz, MD, University of California, San Francisco
  • Principal Investigator: Ryan Rampersaud, MD, PhD, University of California, San Francisco

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 16, 2010

Primary Completion (Actual)

August 20, 2025

Study Completion (Actual)

August 22, 2025

Study Registration Dates

First Submitted

January 31, 2006

First Submitted That Met QC Criteria

January 31, 2006

First Posted (Estimated)

February 2, 2006

Study Record Updates

Last Update Posted (Estimated)

September 23, 2025

Last Update Submitted That Met QC Criteria

September 18, 2025

Last Verified

September 1, 2025

More Information

Terms related to this study

Other Study ID Numbers

  • 10-00825
  • R01MH083784 (U.S. NIH Grant/Contract)
  • K08MH126192 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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