Comparing Effectiveness of Duloxetine and Desipramine in Patients With Chronic Pain: A Pragmatic Trial Using Point of Care Randomization

Over 100 million Americans suffer from chronic pain resulting in annual cost of roughly $635 billion. Limited treatments are available for this widespread disease. The data supporting these treatments lack generalizability to patients with more serious medical and psychological comorbidities who are often excluded from explanatory efficacy trials. Our work aims to integrate randomized comparative effectiveness research with patient care. The investigators will randomize the patients and collect data using an open-source learning healthcare system already in use in our department to monitor patients' progress: Collaborative Health Outcomes Information Registry (CHOIR). Collaborative Health Outcomes Information Registry uses the National Institute of Health Patient Reported Outcomes Measurement Information System item banks for comparative metrics through computer adaptive testing. The investigators will leverage the advantage of this novel system to compare effectiveness of duloxetine and desipramine in decreasing pain in patients with chronic pain. The investigators will also compare adherence of patients to these two commonly used medications over a period of six months. This will evaluate feasibility of integrating randomized comparative effectiveness research with patient care in subspecialty clinics. Collaborative Health Outcomes Information Registry can then be applied for numerous future trials to advance our knowledge in perioperative and pain medicine.

Study Overview

• Status: Completed
• Conditions: Chronic Pain
• Intervention / Treatment: Drug: Duloxetine; Drug: Desipramine

• Study Type: Interventional
• Enrollment (Actual): 86
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • California
    • Redwood City, California, United States, 94063
      • Stanford Pain Management Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion criteria:

1. Age of 18 years old or above
2. Persistent pain for more than 3 months
3. Candidate for treatment by anti-depressant based on treating pain provider

Exclusion criteria:

1. Prior failure of duloxetine and/or desipramine (patients who have failed other TCAs or SNRIs can be considered for the trial based on the reason for previous medication failure)
2. Contraindication to taking duloxetine or desipramine
3. Patient refusal

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Duloxetine; Duloxetine starting at 20 mg per day and increasing to 60 mg per day as tolerated.	Drug: Duloxetine; Open label prescription; Other Names: Cymbalta
Experimental: Desipramine; Desipramine starting at 25 mg per day and increasing to 75 mg per day as tolerated.	Drug: Desipramine; Open label prescription; Other Names: Norpramin

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain Intensity	Percent of participants in each arm that had more than 30% reduction in pain intensity. Participants rated their pain on an 11-point scale (0 to 10; 0 = no pain, 10 = worst pain imaginable).	baseline and 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physical Function	National Institute of Health Patient Reported Outcomes Measurement Information System Standardized score for physical function. Raw scores were converted to T-scores with a population mean of 50 with standard deviation of 10. Overall score range: 0 to 100, higher scores correspond to better function.	Baseline and 6 months
Pain Interference	National Institute of Health Patient Reported Outcomes Measurement Information System Standardized score for pain interference. Raw scores were converted to T-scores with a population mean of 50 with standard deviation of 10. Overall score range: 0 to 100, higher scores correspond to worse pain interference.	Baseline and 6 months
Depression	National Institute of Health Patient Reported Outcomes Measurement Information System Standardized score for depression. Raw scores were converted to T-scores with a population mean of 50 with standard deviation of 10. Overall score range: 0 to 100, higher scores correspond to more severe depression.	Baseline and 6 months
Anxiety	National Institute of Health Patient Reported Outcomes Measurement Information System Standardized score for anxiety. Raw scores were converted to T-scores with a population mean of 50 with standard deviation of 10. Overall score range: 0 to 100, higher scores correspond to more severe anxiety.	Baseline and 6 months
Adherence	Number of participants who completed 6-month therapy based on prescription records.	Monthly for 6 months

Collaborators and Investigators

• Sponsor: Stanford University
• Investigators: Principal Investigator: Vafi Salmasi, MD., Stanford University

Study record dates

Study Major Dates

• Study Start (Actual): September 20, 2018
• Primary Completion (Actual): December 24, 2023
• Study Completion (Actual): June 26, 2024

Study Registration Dates

• First Submitted: April 17, 2018
• First Submitted That Met QC Criteria: May 24, 2018
• First Posted (Actual): June 7, 2018

Study Record Updates

• Last Update Posted (Estimated): November 6, 2025
• Last Update Submitted That Met QC Criteria: October 22, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Chronic Pain; Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, Fused-Ring; Thiophenes; Dibenzazepines; Heterocyclic Compounds, 3-Ring; Duloxetine Hydrochloride; Desipramine
• Other Study ID Numbers: 44758

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No