Comparison of Surgery and Medicine on the Impact of Diverticulitis (COSMID) Trial

NCT ID: NCT04095663

Last Updated: 2025-11-13

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

RECRUITING

Clinical Phase

NA

Total Enrollment

250 participants

Study Classification

INTERVENTIONAL

Study Start Date

2019-10-01

Study Completion Date

2027-02-01

Brief Summary

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The COSMID (Comparison of Surgery and Medicine on the Impact of Diverticulitis) trial is a pragmatic, patient-level randomized superiority trial of elective colectomy vs. best medical management for patients with quality of life (QoL) limiting diverticular disease. A parallel observational cohort will include those who are disinclined to have their treatment choice randomized, but are willing to contribute information about their outcomes. The goal of the COSMID trial is to answer the question: For patients with QoL-limiting diverticular disease, is elective colectomy more effective than best medical management? The hypothesis being tested in the COSMID trial is that patient-reported outcomes (PROs) among patients in the surgery arm will be superior to those in the best medical management arm.

Detailed Description

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For over 50 years, professional society recommendations for the management of uncomplicated diverticulitis included early elective surgery to prevent the need for an emergency operation and avoid the risk of colostomy. Over the last 15 years the notion that a patient must have a certain number of episodes of acute uncomplicated diverticulitis (AUD) before undergoing elective colectomy has changed dramatically. This was, in part, due to studies showing that emergency surgery for complicated disease is much more likely to be needed during the first episode of diverticulitis, making the notion of prophylactic elective colectomy for AUD less relevant. Furthermore, clinicians realized that most recurrent episodes of AUD could be managed with outpatient antibiotics alone and that "best medical management" - including fiber supplementation, mesalazine, rifamycin and probiotics - could reduce symptoms between episodes of AUD. All of the components of best medical management have some, albeit limited, evidence of effectiveness, most in improving symptoms rather than reducing the risk of recurrence and are relatively safe and inexpensive. Best medical management is far less invasive than elective surgery but infrequently prescribed the US, in part because of limited insurance coverage. Alternatively, resection removes the diseased segment of colon, does relieve symptoms and decreases the risk of recurrence.

In 2014, guidelines from the American Society of Colorectal Surgeons (ASCRS) abandoned "episode count" as an indication for surgery in patients with AUD and instead recommended individualizing the decision to operate for AUD based on the "effects on lifestyle (professional and personal) of recurrent attacks". Decision making about surgery in patients with lingering symptoms after recovery from an episode of AUD has not been the specific focus of an ASCRS guideline, but recommendations about elective surgery emphasize individualizing decision making based on the overall impact of the disease on the patient.These recommendations for individualization of treatment based on the quality of life (QoL) impact of recurrent AUD and lingering symptoms highlight the decision that hundreds of thousands of people now have to make each year. Based on the effect of the disease on their QoL they must choose between two very different treatment options: elective colectomy vs. best medical management. While the recommendation to individualize treatment based on the QoL impact is a step forward in advancing patient-centered care, the comparative effectiveness of these two treatments on symptoms and QoL has not been well studied.

This will be a multi-site, open randomized trial in which participants with either recurrent AUD or lingering symptoms after an episode of AUD are randomized to one of two initial treatment strategies, elective segmental colectomy (performed laparoscopically when possible) and best medical management.

Conditions

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Diverticulitis

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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Partial Colectomy

Elective segmental colectomy for diverticular disease involves removal of the segment of colon (most commonly sigmoid and/or left colon) where there has been disease identified by computed tomography imaging or colonoscopy. Elective colectomy usually removes the affected colon along with adjacent segments that have diverticula, with a primary anastomosis performed to reestablish bowel continuity. Most surgeons now perform the procedure using a laparoscopic approach, when possible, and sometimes use a temporary, protective stoma if the re-connection is considered high-risk. The technique for laparoscopic resection is not specified by the protocol (allows for any number of laparoscopic port sites, all incision types, hand-assistance and robotic) with details of the technique recorded. If randomized to elective colectomy, patients will be encouraged to undergo the procedure within 6 weeks of assignment.

Group Type ACTIVE_COMPARATOR

Partial Colectomy

Intervention Type PROCEDURE

Most partial colectomies are performed using a laparoscopic approach, when possible, and surgeons sometimes use a temporary, protective stoma if the re-connection is considered high risk.

Medical Management

Medical management for diverticular disease has been used for over 30 years and includes a set of interventions, all components of which have been the subject of small, but often positive trials. All patients randomized to medical management or who select it as their treatment in the observational cohort will view a video (provided in English and Spanish) that explains each element of the medical management "toolbox": diet and exercise recommendations, fiber supplementation (e.g., augmenting dietary fiber or over the counter fiber supplements), with mesalazine tablets or suppositories, probiotics and rifamycin. In consultation with their physician, they will be recommended to a regimen of diet and exercise and fiber supplementation. Clinicians will be asked to consider rifamycin (dose/frequency) for those with AUD who are not responding to diet and exercise and mesalazine (dose/frequency) for those with lingering symptoms who are not responding to diet and exercise.

Group Type ACTIVE_COMPARATOR

Medical Management

Intervention Type OTHER

Patients will be offered a varying combination of tools from the best medical management "toolbox" (diet and exercise, fiber supplementation/probiotics, and rifamycin/mesalazine) depending on what they have already tried. Based on the "evidence-based best medical toolbox" clinicians will be asked to consider rifamycin (dose/frequency) for those with AUD who are not responding to diet and exercise and mesalazine (dose/frequency) for those with lingering symptoms who are not responding to diet and exercise.

Interventions

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Partial Colectomy

Most partial colectomies are performed using a laparoscopic approach, when possible, and surgeons sometimes use a temporary, protective stoma if the re-connection is considered high risk.

Intervention Type PROCEDURE

Medical Management

Patients will be offered a varying combination of tools from the best medical management "toolbox" (diet and exercise, fiber supplementation/probiotics, and rifamycin/mesalazine) depending on what they have already tried. Based on the "evidence-based best medical toolbox" clinicians will be asked to consider rifamycin (dose/frequency) for those with AUD who are not responding to diet and exercise and mesalazine (dose/frequency) for those with lingering symptoms who are not responding to diet and exercise.

Intervention Type OTHER

Eligibility Criteria

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Inclusion Criteria

* Adults ≥18 years
* At least one episode of diverticulitis confirmed by CT scan and a colonoscopy (completed or scheduled) to rule out or screen for other colon pathology in accordance with colorectal cancer screening guidelines
* Persistent signs, symptoms, or concerns related to diverticulitis after recovery from an episode of left-sided diverticulitis
* Self-reported QoL limitation (assessed with 12 questions modified from the Diverticulitis Quality of Life \[DV-QOL\] instrument).

Exclusion Criteria

* Unable to consent in English or Spanish
* Current diagnosis or previous endoscopic or surgical interventions for fistula, or stricture or current significant bleeding, related to diverticulitis
* Last episode of acute diverticulitis currently unresolved (i.e., on antibiotics for diverticulitis; drain in place)
* Previous operation for diverticulitis
* Right-sided diverticulitis
* Immunodeficiency (e.g., absolute neutrophil count \<500/mm3, chronic immunosuppressive drugs like oral corticosteroids, anti-TNF agents, or known AIDS \[i.e., recent CD4 count \<200\] assessed by patient history)
* Actively undergoing chemotherapy or radiation for malignancy
* Expectant or concurrent hemodialysis, peritoneal dialysis, treatments using indwelling venous catheters, or conditions putting patient at risk for bacterial seeding
* Diagnosis of inflammatory bowel disease (i.e., Crohn's, ulcerative colitis)
* Taking prescription medication for irritable bowel syndrome
* Intolerance or allergy to all medications in the medical management arm
* Surgeon is unwilling to offer surgery due to comorbid or prior surgical conditions that contraindicate elective surgery (e.g., liver failure, renal failure, malignancy, "frozen abdomen")
* Abdominal/pelvic surgery within the past month
* Pregnant or expecting to become pregnant in the 30 days following baseline/screening
* Unable to consent to research or self-respond to follow-up surveys (e.g., altered mental status)
* Currently incarcerated in a detention facility or in police custody at baseline/screening (patients wearing a monitoring device can be enrolled)
* Prior enrollment in the COSMID study or planning on enrollment in another investigational drug or vaccine while on study treatment
* Unable or unwilling to return, be contacted for, or complete research surveys.
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Patient-Centered Outcomes Research Institute

OTHER

Sponsor Role collaborator

University of Washington

OTHER

Sponsor Role lead

Responsible Party

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David Flum

Professor, School of Medicine: Surgery

Responsibility Role PRINCIPAL_INVESTIGATOR

Principal Investigators

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David R Flum, MD

Role: PRINCIPAL_INVESTIGATOR

University of Washington

Locations

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Cedars-Sinai Medical Center

Los Angeles, California, United States

Site Status ACTIVE_NOT_RECRUITING

UC San Diego Health

San Diego, California, United States

Site Status ACTIVE_NOT_RECRUITING

UCSF Health

San Francisco, California, United States

Site Status RECRUITING

Stanford University Medical Center

Stanford, California, United States

Site Status RECRUITING

University of Colorado

Denver, Colorado, United States

Site Status RECRUITING

University of Florida

Gainesville, Florida, United States

Site Status RECRUITING

University of South Florida

Tampa, Florida, United States

Site Status RECRUITING

Memorial Health University Medical Center

Savannah, Georgia, United States

Site Status RECRUITING

Rush University Medical Center

Chicago, Illinois, United States

Site Status RECRUITING

Northwestern University

Evanston, Illinois, United States

Site Status RECRUITING

University of Iowa Healthcare

Iowa City, Iowa, United States

Site Status RECRUITING

Boston University Medical Center

Boston, Massachusetts, United States

Site Status RECRUITING

Lahey Clinic

Burlington, Massachusetts, United States

Site Status RECRUITING

Albany Medical College

Albany, New York, United States

Site Status ACTIVE_NOT_RECRUITING

New York Presbyterian-Queens

Flushing, New York, United States

Site Status RECRUITING

Columbia University Medical Center

New York, New York, United States

Site Status RECRUITING

Weill Cornell Medicine

New York, New York, United States

Site Status RECRUITING

University of Rochester Medical Center

Rochester, New York, United States

Site Status RECRUITING

Atrium Health-Carolinas Medical Center

Charlotte, North Carolina, United States

Site Status RECRUITING

Mount Carmel Health Systems

Columbus, Ohio, United States

Site Status RECRUITING

Penn Medicine

Philadelphia, Pennsylvania, United States

Site Status ACTIVE_NOT_RECRUITING

Allegheny-Singer Research Institute

Pittsburgh, Pennsylvania, United States

Site Status RECRUITING

Medical University of South Carolina

Charleston, South Carolina, United States

Site Status RECRUITING

UT Southwestern Medical Center

Dallas, Texas, United States

Site Status ACTIVE_NOT_RECRUITING

UTHealth Houston

Houston, Texas, United States

Site Status RECRUITING

University of Utah Health

Salt Lake City, Utah, United States

Site Status RECRUITING

VCU Medical Center

Richmond, Virginia, United States

Site Status RECRUITING

Benaroya Research Institute at Virginia Mason

Seattle, Washington, United States

Site Status RECRUITING

University of Washington

Seattle, Washington, United States

Site Status RECRUITING

Countries

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United States

Central Contacts

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Kelsey M Pullar, MPH

Role: CONTACT

Phone: 206 221-8247

Email: [email protected]

Erin E Fannon

Role: CONTACT

Phone: 206 685-9770

Email: [email protected]

Facility Contacts

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Jenny Broering

Role: primary

Kristen Davis

Role: primary

Tracey MacDermott

Role: primary

Amber Bouton

Role: primary

Avennette Pinto

Role: primary

Anne Brooks

Role: primary

Matthew Johnson

Role: primary

Rose Arrieta

Role: primary

Jessica Danielson

Role: primary

Marina Malikova

Role: primary

Kameron Ky

Role: primary

Susan Ingenito

Role: primary

Ken Watanabe

Role: primary

Jordan Augsburger

Role: primary

I Marianetti

Role: primary

Colie Kaiser

Role: primary

Sheila Brooks

Role: primary

Rachel Reading

Role: primary

Natalie Koren

Role: primary

Debbie Nguyen

Role: primary

Jordan Esplin

Role: primary

Jinfeng Han

Role: primary

Audrey Merz

Role: primary

Mariam Hantouli, MD

Role: primary

Kelsey Pullar, MPH

Role: backup

Other Identifiers

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STUDY00007409

Identifier Type: -

Identifier Source: org_study_id