A Study of PF-08653945 and PF-08653944 in Adults With Overweight or Obesity
SOLIS-1
A PHASE 2B, RANDOMIZED, PLACEBO-CONTROLLED, DOUBLE-BLIND, DOSE-RANGING, DOSE-FINDING, UMBRELLA STUDY TO EVALUATE EFFICACY AND SAFETY OF PF-08653945 AND PF-08653944, ALONE OR IN COMBINATION, IN ADULTS WITH OVERWEIGHT OR OBESITY (SOLIS-1)
2 other identifiers
interventional
940
2 countries
63
Brief Summary
This study is being done to learn about the safety and effects of the study drugs, PF-08653945 and PF-08653944, when given alone or together for weight loss, compared to a placebo (a dummy drug that has no active ingredient in it).
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_2
Started May 2026
63 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
May 4, 2026
CompletedFirst Posted
Study publicly available on registry
May 8, 2026
CompletedStudy Start
First participant enrolled
May 11, 2026
CompletedPrimary Completion
Last participant's last visit for primary outcome
August 4, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
January 5, 2028
September 14, 2026
September 1, 2026
1.2 years
May 4, 2026
September 9, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
Percent change from baseline in body weight
Baseline (Week 0) to Week 48
Secondary Outcomes (8)
Percent change from baseline in body weight
Baseline (Week 0) to Week 60
Change from baseline in body weight
Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥5% of body weight reduction from baseline
Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥10% of body weight reduction from baseline
Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥15% of body weight reduction from baseline
Baseline (Week 0) to Week 48 and Week 60
- +3 more secondary outcomes
Study Arms (3)
Cohort 1
EXPERIMENTALParticipants receive subcutaneous injections of PF-08653945 or placebo.
Cohort 2
EXPERIMENTALParticipants receive subcutaneous injections of PF-08653945 + PF-08653944 or placebo.
Cohort 3
EXPERIMENTALParticipants receive subcutaneous injections of PF-08653945 + PF-08653944 , PF-08653944 , or placebo.
Interventions
Eligibility Criteria
You may qualify if:
- Eligible participants for this study include:
- adults aged 18 years or older with
- obesity (BMI of 30.0 kg/m2 to 50.0 kg/m2) or with
- overweight (BMI of 27.0 kg/m2 to \<30.0 kg/m2) who also have at least 1 prespecified weight-related comorbidity (hypertension, dyslipidemia, cardiovascular disease, or obstructive sleep apnea), at the screening visit.
You may not qualify if:
- Participants who are not eligible include those with diabetes mellitus, a body weight change of \>5% or use of weight loss medications in the 12 weeks prior to screening, a history of or plan for surgical treatment for obesity, and those who are unable or unwilling to comply with contraceptive requirements or are pregnant or lactating.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (63)
Clinical Research Institute of Arizona
Sun City West, Arizona, 85375, United States
San Fernando Valley Health Institute
Canoga Park, California, 91304, United States
Ark Clinical Research
Fountain Valley, California, 92708, United States
Paragon Rx Clinical
Garden Grove, California, 92840, United States
Torrance Clinical Research Institute, Inc.
Lomita, California, 90717, United States
Ark Clinical Research
Long Beach, California, 90815, United States
Collaborative Neuroscience Research, LLC
Los Alamitos, California, 90720, United States
Paradigm Clinical Research-Modesto
Modesto, California, 95355, United States
Paradigm Clinical Research Centers, LLC
San Diego, California, 92108, United States
University Clinical Investigators, Incorporated
Tustin, California, 92780, United States
Diablo Clinical Research, LLC dba Flourish Research
Walnut Creek, California, 94598, United States
AGA Clinical Trials
Hialeah, Florida, 33012, United States
Westside Center for Clinical Research
Jacksonville, Florida, 32205, United States
New Horizon Research Center
Miami, Florida, 33165, United States
Charter Research
Orlando, Florida, 32803, United States
Atlanta Diabetes Associates
Atlanta, Georgia, 30318, United States
Clinical Research Atlanta
Stockbridge, Georgia, 30281, United States
Koch Family Medicine Clinical Research/Elite Research Network
Morton, Illinois, 61550, United States
Bioluminux Clinical Research Illinois
Naperville, Illinois, 60540, United States
Johnson County Clinical Trials
Lenexa, Kansas, 66219, United States
DelRicht Research
Mandeville, Louisiana, 70471, United States
DelRicht Research
Prairieville, Louisiana, 70769, United States
Patient First Clinical Trials (PFCTRIALS)
Lutherville, Maryland, 21093, United States
DelRicht Research
Springfield, Missouri, 65807, United States
Mercury Street Medical Group, PLLC
Butte, Montana, 59701, United States
Alliance Clinical Research Las Vegas (Excel Clinical Research)
Las Vegas, Nevada, 89109, United States
AB Clinical Trials
Las Vegas, Nevada, 89119, United States
Palm Research Center
Las Vegas, Nevada, 89128, United States
Bioluminux Clinical Research
Hamilton, New Jersey, 08690, United States
DelRicht Research
Charlotte, North Carolina, 28211, United States
Monroe Biomedical Research
Monroe, North Carolina, 28112, United States
Piedmont Healthcare
Statesville, North Carolina, 28625, United States
Accellacare - Wilmington
Wilmington, North Carolina, 28401, United States
Tekton Research, LLC.
Oklahoma City, Oklahoma, 73134, United States
Preferred Primary Care Physicians
Pittsburgh, Pennsylvania, 15236, United States
Preferred Primary Care Physicians, Inc.
Uniontown, Pennsylvania, 15401, United States
Preferred Primary Care Physicians
Uniontown, Pennsylvania, 15401, United States
TMA Headlands LLC (d/b/a Trial Management Associates)
Myrtle Beach, South Carolina, 29572, United States
DelRicht Research
Hendersonville, Tennessee, 37075, United States
Cedar Health Research - Euless
Euless, Texas, 76040, United States
JCCT-JUNO NW Houston
Houston, Texas, 77040, United States
Activian Clinical Research
Kingwood, Texas, 77339, United States
3A Research
Plano, Texas, 75093, United States
DelRicht Research @ Zomnir Family Medicine
Prosper, Texas, 75078, United States
Worldwide Clinical Trials
San Antonio, Texas, 78217, United States
Tekton Research, LLC.
San Antonio, Texas, 78258, United States
Consano Clinical Research, LLC
Shavano Park, Texas, 78231, United States
DM Clinical Research
Tomball, Texas, 77375, United States
Alpine Medical Group
Salt Lake City, Utah, 84102, United States
Wasatch Clinical Research, LLC
Salt Lake City, Utah, 84107, United States
Washington Center for Weight Management and Research
Arlington, Virginia, 22206, United States
Manassas Clinical Research Center
Manassas, Virginia, 20110, United States
DelRicht Research
Vienna, Virginia, 22182, United States
Viable Clinical Research Corporation
Bridgewater, Nova Scotia, B4V 3N2, Canada
Aggarwal and Associates Limited
Brampton, Ontario, L6T 0G1, Canada
Centricity Research Etobicoke Endocrinology
Etobicoke, Ontario, M9R 4E1, Canada
Milestone Research Inc.
London, Ontario, N5W 6A2, Canada
Bluewater Clinical Research Group Inc.
Sarnia, Ontario, N7T 4X3, Canada
Dr. Anil K. Gupta Medicine Professional Corporation
Toronto, Ontario, M9V 4B4, Canada
Centricity Research Toronto Manna Multispecialty
Toronto, Ontario, M9W 4L6, Canada
Ecogene-21
Chicoutimi, Quebec, G7H 7K9, Canada
Centricity Research Mirabel Multispecialty
Mirabel, Quebec, J7J 2K8, Canada
Recherche GCP Research
Montreal, Quebec, H1Y 3H5, Canada
Related Links
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Study Design
- Study Type
- interventional
- Phase
- phase 2
- Allocation
- RANDOMIZED
- Masking
- DOUBLE
- Who Masked
- PARTICIPANT, INVESTIGATOR
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
May 4, 2026
First Posted
May 8, 2026
Study Start
May 11, 2026
Primary Completion (Estimated)
August 4, 2027
Study Completion (Estimated)
January 5, 2028
Last Updated
September 14, 2026
Record last verified: 2026-09
Data Sharing
- IPD Sharing
- Will share
Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.