Ixekizumab Concomitantly Administered With Tirzepatide in Adults With Moderate-to-Severe Plaque Psoriasis and Obesity or Overweight (TOGETHER-PsO)

June 16, 2026 updated by: Eli Lilly and Company

Efficacy and Safety of Ixekizumab or Ixekizumab Concomitantly Administered With Tirzepatide in Adult Participants With Moderate-to-Severe Plaque Psoriasis and Obesity or Overweight: A Phase 3b, Randomized, Multicenter, Open-Label Study (TOGETHER-PsO)

The main purpose of this study is to demonstrate that when participants with moderate to severe plaque psoriasis and obesity or overweight in the presence of at least 1 weight-related comorbid condition receive ixekizumab and tirzepatide concomitantly administered, participants see improvement in their psoriasis and achieve weight reduction compared to when receiving ixekizumab.

Participation in this study includes up to 12 visits and could last up to 61 weeks including screening, open label treatment period, and post-treatment follow-up period.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

281

Phase

  • Phase 3

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

  • Puerto Rico
      • Bayamón, Puerto Rico, 00961
        • SCB Research Center
      • Carolina, Puerto Rico, 00985
        • Office of Dr. Alma M. Cruz
      • San Juan, Puerto Rico, 00918
        • Mindful Medical Research
      • San Juan, Puerto Rico, 00917
        • GCM Medical Group, PSC - Hato Rey Site
  • United States
    • Alabama
      • Birmingham, Alabama, United States, 35203
        • Total Skin & Beauty Dermatology Center, PC DBA Total Dermatology
    • Arizona
      • Phoenix, Arizona, United States, 85006
        • Medical Dermatology Specialists
      • Scottsdale, Arizona, United States, 85260
        • Scottsdale Clinical Trials
      • Yuma, Arizona, United States, 85365
        • Yuma Clinical Trials
    • Arkansas
      • Fort Smith, Arkansas, United States, 72916
        • Johnson Dermatology
    • California
      • Encinitas, California, United States, 92024
        • California Dermatology & Clinical Research Institute
      • Fountain Valley, California, United States, 92708
        • First OC Dermatology Research Inc
      • Laguna Niguel, California, United States, 92677
        • Avance Clinical Trials
      • Los Angeles, California, United States, 90045
        • Dermatology Research Associates
      • Los Angeles, California, United States, 90017
        • Metropolis Dermatology
      • Northridge, California, United States, 91325
        • Northridge Clinical Trials
      • Oxnard, California, United States, 93030
        • Cura Clinical Research - Oxnard
      • Sacramento, California, United States, 95815
        • Integrative Skin Science and Research - Location 2
      • San Diego, California, United States, 92123
        • Therapeutics Clinical Research
    • Florida
      • Coral Springs, Florida, United States, 33071
        • Life Clinical Trials
      • Fort Myers, Florida, United States, 33912
        • Alliance for Multispecialty Research, LLC
      • Hialeah, Florida, United States, 33016
        • Neoclinical Research
      • Hollywood, Florida, United States, 33021
        • Skin Care Research
      • Hollywood, Florida, United States, 33024
        • Encore Medical Research
      • Jacksonville, Florida, United States, 32256
        • Solutions Through Advanced Research
      • Miami Lakes, Florida, United States, 33014
        • Deluxe Health Center
      • Ocala, Florida, United States, 34470
        • Renstar Medical Research
      • Plantation, Florida, United States, 33317
        • Leading Edge Dermatology
      • Sanford, Florida, United States, 32771
        • International Clinical Research - Sanford
      • Tampa, Florida, United States, 33609
        • Palm Harbor Dermatology PA d/b/a TrueBlue Clinical Research
      • Tampa, Florida, United States, 33607
        • Nodal Medical Center
    • Illinois
      • Chicago, Illinois, United States, 60602
        • DeNova Research
      • Naperville, Illinois, United States, 60563
        • Oak Dermatology
    • Indiana
      • Indianapolis, Indiana, United States, 46250
        • Dawes Fretzin Clinical Research Group, LLC
      • Plainfield, Indiana, United States, 46168
        • The Indiana Clinical Trials Center, PC
    • Kentucky
      • Bowling Green, Kentucky, United States, 42104
        • Equity Medical - Bowling Green
    • Louisiana
      • Baton Rouge, Louisiana, United States, 70809
        • DelRicht Research
      • Lake Charles, Louisiana, United States, 70601
        • Care Access - Lake Charles (Bayou Pines)
    • Maryland
      • Rockville, Maryland, United States, 20850
        • Lawrence J. Green, MD, LLC
      • Rockville, Maryland, United States, 20850
        • Dermatology and Skin Cancer Specialists, LLC
    • Michigan
      • Bay City, Michigan, United States, 48706
        • Great Lakes Research Group, Inc.
      • Caledonia, Michigan, United States, 49316
        • The Derm Institute of West Michigan
      • Northville, Michigan, United States, 48167
        • MI Skin Innovations
    • Nevada
      • Las Vegas, Nevada, United States, 89144
        • Las Vegas Dermatology
      • Reno, Nevada, United States, 89509
        • Skin Cancer and Dermatology Institute - Reno
    • New Hampshire
      • Portsmouth, New Hampshire, United States, 03801
        • ActivMed Practices & Research, LLC.
    • New Jersey
      • East Windsor, New Jersey, United States, 08520
        • Psoriasis Treatment Center of Central New Jersey
      • Hoboken, New Jersey, United States, 07030
        • Care Access - Hoboken
    • New York
      • New York, New York, United States, 10023
        • Equity Medical
      • New York, New York, United States, 10028
        • Mount Sinai Doctors - East 85th Street
    • North Carolina
      • Huntersville, North Carolina, United States, 28078
        • Onsite Clinical Solutions - Huntersville
    • North Dakota
      • Fargo, North Dakota, United States, 58103
        • Red River Research Partners
    • Ohio
      • Boardman, Ohio, United States, 44512
        • Optima Research - Boardman
      • Mason, Ohio, United States, 45040
        • Dermatologists of Southwest Ohio
    • Oregon
      • Portland, Oregon, United States, 97210
        • Oregon Dermatology and Research Center
      • Portland, Oregon, United States, 97201
        • Oregon Medical Research Center
    • Pennsylvania
      • Plymouth Meeting, Pennsylvania, United States, 19462
        • Dermatology Associates of Plymouth Meeting
    • South Carolina
      • Columbia, South Carolina, United States, 29212
        • Columbia Dermatology & Aesthetics
    • Tennessee
      • Murfreesboro, Tennessee, United States, 37130
        • International Clinical Research - Tennessee LLC
      • Smyrna, Tennessee, United States, 37167
        • DelRicht Research - Thompson's Station
    • Texas
      • Austin, Texas, United States, 78746
        • Tekton Research - Westlake Drive
      • Bellaire, Texas, United States, 77401
        • Bellaire Dermatology Associates
      • Dallas, Texas, United States, 75231
        • Modern Research Associates, PLLC
      • Pflugerville, Texas, United States, 78660
        • Austin Institute for Clinical Research
      • San Antonio, Texas, United States, 78218
        • Texas Dermatology and Laser Specialists
      • San Antonio, Texas, United States, 78229
        • Dermatology Clinical Research Center of San Antonio
      • San Antonio, Texas, United States, 78213
        • Progressive Clinical Research
    • Utah
      • Layton, Utah, United States, 84041
        • Tanner Clinic
    • Virginia
      • Arlington, Virginia, United States, 22206
        • Care Access - Arlington
      • Danville, Virginia, United States, 24541
        • Care Access - Danville
      • Norfolk, Virginia, United States, 23502
        • Virginia Clinical Research, Inc.
    • Washington
      • Bellevue, Washington, United States, 98004
        • Bellevue Dermatology Clinic
      • Burien, Washington, United States, 98168
        • Dermatology Of Seattle

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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Have a diagnosis of moderate-to-severe plaque psoriasis (PsO) for at least 6 months.
  • Have both a Static Physician's Global Assessment (sPGA) score of ≥3 and a Psoriasis Area and Severity Index (PASI) ≥12.
  • Have ≥10% body surface area (BSA) involvement.
  • Have obesity, body mass index of ≥30 kilograms per meter squared (BMI ≥30 kg/m²) or overweight (BMI ≥27 to <30 kg/m²) in the presence of at least 1 of these weight-related comorbid conditions (hypertension, dyslipidemia, obstructive sleep apnea, cardiovascular disease, or T2DM).

Exclusion Criteria:

Medical Conditions

  • Have Type 1 Diabetes Mellitus (T1DM).
  • Have insulin-treated Type 2 Diabetes Mellitus (T2DM).
  • Have a prior or planned surgical treatment for obesity.
  • Have a family or personal history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia (MEN) syndrome type 2.
  • Have active, or a history of inflammatory bowel disease (Crohn's or ulcerative colitis).

  • Have a diagnosis or history of malignant disease within the 5 years prior to randomization, with the following exceptions:

    • basal cell or squamous epithelial carcinomas of the skin that have been resected, with no evidence of metastatic disease for 3 years.
    • cervical carcinoma in situ, with no evidence of recurrence within the 5 years prior to randomization.
  • Have serious disorder or illness other than PsO.
  • Have a history of chronic or acute pancreatitis.
  • Have any prior use of ixekizumab or tirzepatide.
  • Have a previous failure or intolerance to an interleukin 17 inhibitor (IL-17i) or glucagon-like peptide 1 (GLP-1) receptor agonists.

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: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Ixekizumab
Ixekizumab administered subcutaneous (SC).
Drug: Ixekizumab
Administered SC
Other Names:
  • LY2439821
Experimental: Ixekizumab and Tirzepatide
Ixekizumab concomitantly administered with tirzepatide SC.
Drug: Ixekizumab
Administered SC
Other Names:
  • LY2439821
Drug: Tirzepatide
Administered SC.
Other Names:
  • LY3298176

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of Participants Who Simultaneously Achieved Psoriasis Area and Severity Index (PASI) 100 and At Least 10% Weight Reduction
Time Frame: Baseline to Week 36
PASI combines the extent of body surface involvement in 4 anatomical regions (head, trunk, arms, and legs). For each region the percent area of skin involved was estimated from 0 (0%) to 6 (90%-100%) and severity was estimated by clinical signs of erythema, induration and scaling with a scores range from 0 (none) to 4 (very severe). Each area is scored separately and the scores then combined for the final PASI. Final PASI calculated as: sum of severity parameters for each region * area score * weighing factor (head [0.1], upper limbs [0.2], trunk [0.3], lower limbs [0.4]). Overall scores range from 0 (no psoriasis) to 72 (the most severe disease).Participants achieving PASI 100 were defined as having an improvement of at least 100% in the PASI score compared to baseline.
Baseline to Week 36

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Percentage of Participants Who Simultaneously Achieved PASI 75 and At Least 5% Weight Reduction
Time Frame: Baseline to Week 36
PASI combines the extent of body surface involvement in 4 anatomical regions (head, trunk, arms, and legs). For each region the percent area of skin involved was estimated from 0 (0%) to 6 (90%-100%) and severity was estimated by clinical signs of erythema, induration and scaling with a scores range from 0 (none) to 4 (very severe). Each area is scored separately, and the scores then combined for the final PASI. Final PASI calculated as: sum of severity parameters for each region * area score * weighing factor (head [0.1], upper limbs [0.2], trunk [0.3], lower limbs [0.4]). Overall scores range from 0 (no psoriasis) to 72 (the most severe disease). Participants achieving PASI 75 were defined as having an improvement of ≥75% in the PASI score compared to baseline.
Baseline to Week 36
Percentage of Participants Achieving PASI 100
Time Frame: Baseline to Week 36
PASI combines the extent of body surface involvement in 4 anatomical regions (head, trunk, arms, and legs). For each region the percent area of skin involved was estimated from 0 (0%) to 6 (90%-100%) and severity was estimated by clinical signs of erythema, induration and scaling with a scores range from 0 (none) to 4 (very severe). Each area is scored separately, and the scores then combined for the final PASI. Final PASI calculated as: sum of severity parameters for each region * area score * weighing factor (head [0.1], upper limbs [0.2], trunk [0.3], lower limbs [0.4]). Overall scores range from 0 (no psoriasis) to 72 (the most severe disease). Participants achieving PASI 100 were defined as having an improvement of at least 100% in the PASI scores compared to baseline.
Baseline to Week 36
Percentage of Participants Achieving At Least 10% Weight Reduction
Time Frame: Baseline to Week 36
Percentage of Participants Who Achieved at Least a 10% Weight Reduction
Baseline to Week 36

Collaborators and Investigators

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

Sponsor

Eli Lilly and Company

Investigators

  • Study Director: Call 1-877-CTLILLY (1-877-285-4559) or 1-317-615-4559 Mon - Fri 9 AM - 5 PM Eastern time (UTC/GMT - 5 hours, EST), Eli Lilly and Company

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.

General Publications

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)

September 30, 2024

Primary Completion (Actual)

January 8, 2026

Study Completion (Actual)

June 1, 2026

Study Registration Dates

First Submitted

September 4, 2024

First Submitted That Met QC Criteria

September 5, 2024

First Posted (Actual)

September 19, 2024

Study Record Updates

Last Update Posted (Actual)

June 17, 2026

Last Update Submitted That Met QC Criteria

June 16, 2026

Last Verified

June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 27243
  • I1F-MC-RHDC (Other Identifier: Eli Lilly and Company)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

Anonymized individual patient level data will be provided in a secure access environment upon approval of a research proposal and a signed data sharing agreement.

IPD Sharing Time Frame

Data are available 6 months after the primary publication and approval of the indication studied in the US and EU, whichever is later. Data will be indefinitely available for requesting.

IPD Sharing Access Criteria

A research proposal must be approved by an independent review panel and researchers must sign a data sharing agreement.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

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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