OverweightPhase 2SOLIS-1NCT07575932
A Study of PF-08653945 and PF-08653944 in Adults With Overweight or Obesity
A Phase 2 study testing PF-08653945 and PF-08653944 in people with Overweight and Obesity, run by Pfizer at 63 sites in 2 countries.
Trial 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). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Overweight, Obesity, Overweight and/or Obesity
- What is being tested?
- PF-08653945 and PF-08653944
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 940 participants
- Where
- 63 sitesin 2 countries
- Study dates
- 11 May 2026to 5 Jan 2028
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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.
Who cannot join
- 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.
Trial locations and contacts
63 sites in 2 countries.
63 sites in 2 countries
United States53 sites
Washington Center for Weight Management and Research
Arlington, Virginia, 22206
Atlanta Diabetes Associates
Atlanta, Georgia, 30318
Mercury Street Medical Group, PLLC
Butte, Montana, 59701
San Fernando Valley Health Institute
Canoga Park, California, 91304
DelRicht Research
Charlotte, North Carolina, 28211
Cedar Health Research - Euless
Euless, Texas, 76040
Ark Clinical Research
Fountain Valley, California, 92708
Paragon Rx Clinical
Garden Grove, California, 92840
Bioluminux Clinical Research
Hamilton, New Jersey, 08690
DelRicht Research
Hendersonville, Tennessee, 37075
AGA Clinical Trials
Hialeah, Florida, 33012
JCCT-JUNO NW Houston
Houston, Texas, 77040
Westside Center for Clinical Research
Jacksonville, Florida, 32205
Activian Clinical Research
Kingwood, Texas, 77339
Alliance Clinical Research Las Vegas (Excel Clinical Research)
Las Vegas, Nevada, 89109
AB Clinical Trials
Las Vegas, Nevada, 89119
Palm Research Center
Las Vegas, Nevada, 89128
Johnson County Clinical Trials
Lenexa, Kansas, 66219
Torrance Clinical Research Institute, Inc.
Lomita, California, 90717
Ark Clinical Research
Long Beach, California, 90815
Collaborative Neuroscience Research, LLC
Los Alamitos, California, 90720
Patient First Clinical Trials (PFCTRIALS)
Lutherville, Maryland, 21093
Manassas Clinical Research Center
Manassas, Virginia, 20110
DelRicht Research
Mandeville, Louisiana, 70471
New Horizon Research Center
Miami, Florida, 33165
Paradigm Clinical Research-Modesto
Modesto, California, 95355
Monroe Biomedical Research
Monroe, North Carolina, 28112
Koch Family Medicine Clinical Research/Elite Research Network
Morton, Illinois, 61550
TMA Headlands LLC (d/b/a Trial Management Associates)
Myrtle Beach, South Carolina, 29572
Bioluminux Clinical Research Illinois
Naperville, Illinois, 60540
Tekton Research, LLC.
Oklahoma City, Oklahoma, 73134
Charter Research
Orlando, Florida, 32803
Preferred Primary Care Physicians
Pittsburgh, Pennsylvania, 15236
3A Research
Plano, Texas, 75093
DelRicht Research
Prairieville, Louisiana, 70769
DelRicht Research @ Zomnir Family Medicine
Prosper, Texas, 75078
Alpine Medical Group
Salt Lake City, Utah, 84102
Wasatch Clinical Research, LLC
Salt Lake City, Utah, 84107
Worldwide Clinical Trials
San Antonio, Texas, 78217
Tekton Research, LLC.
San Antonio, Texas, 78258
Paradigm Clinical Research Centers, LLC
San Diego, California, 92108
Consano Clinical Research, LLC
Shavano Park, Texas, 78231
DelRicht Research
Springfield, Missouri, 65807
Piedmont Healthcare
Statesville, North Carolina, 28625
Clinical Research Atlanta
Stockbridge, Georgia, 30281
Clinical Research Institute of Arizona
Sun City West, Arizona, 85375
DM Clinical Research
Tomball, Texas, 77375
University Clinical Investigators, Incorporated
Tustin, California, 92780
Preferred Primary Care Physicians, Inc.
Uniontown, Pennsylvania, 15401
Preferred Primary Care Physicians
Uniontown, Pennsylvania, 15401
DelRicht Research
Vienna, Virginia, 22182
Diablo Clinical Research, LLC dba Flourish Research
Walnut Creek, California, 94598
Accellacare - Wilmington
Wilmington, North Carolina, 28401
Canada10 sites
Aggarwal and Associates Limited
Brampton, Ontario, L6T 0G1
Viable Clinical Research Corporation
Bridgewater, Nova Scotia, B4V 3N2
Ecogene-21
Chicoutimi, Quebec, G7H 7K9
Centricity Research Etobicoke Endocrinology
Etobicoke, Ontario, M9R 4E1
Milestone Research Inc.
London, Ontario, N5W 6A2
Centricity Research Mirabel Multispecialty
Mirabel, Quebec, J7J 2K8
Recherche GCP Research
Montreal, Quebec, H1Y 3H5
Bluewater Clinical Research Group Inc.
Sarnia, Ontario, N7T 4X3
Dr. Anil K. Gupta Medicine Professional Corporation
Toronto, Ontario, M9V 4B4
Centricity Research Toronto Manna Multispecialty
Toronto, Ontario, M9W 4L6
About this study
Official title: 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)
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).
- Conditions
- Overweight, Obesity, Overweight and/or Obesity, Overweight or Obesity, Overnutrition, Nutrition Disorders
- Being tested
- PF-08653945, PF-08653944, Placebo
- Keywords
- Overnutrition, Nutrition Disorders, Nutritional and Metabolic Diseases, Body Weight, Obesity, Overweight, GLP-1RA, Amylin, DACRA
- Medical subject headings
- Overweight, Obesity, Overnutrition, Nutrition Disorders, Nutritional and Metabolic Diseases, Body Weight
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PF-08653945Drug
Subcutaneous Injection
PF-08653944Drug
Subcutaneous Injection
PlaceboDrug
Subcutaneous Injection
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1 | Experimental | Participants receive subcutaneous injections of PF-08653945 or placebo. Receives: Drug: PF-08653945; Drug: Placebo |
| Cohort 2 | Experimental | Participants receive subcutaneous injections of PF-08653945 + PF-08653944 or placebo. Receives: Drug: PF-08653945; Drug: PF-08653944; Drug: Placebo |
| Cohort 3 | Experimental | Participants receive subcutaneous injections of PF-08653945 + PF-08653944 , PF-08653944 , or placebo. Receives: Drug: PF-08653945; Drug: PF-08653944; Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Percent change from baseline in body weight
Measured: Baseline (Week 0) to Week 48
Secondary outcomes (8)
Percent change from baseline in body weight
Measured: Baseline (Week 0) to Week 60
Change from baseline in body weight
Measured: Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥5% of body weight reduction from baseline
Measured: Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥10% of body weight reduction from baseline
Measured: Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥15% of body weight reduction from baseline
Measured: Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥20% of body weight reduction from baseline
Measured: Baseline (Week 0) to Week 48 and Week 60
Percentage of participants who achieve ≥25% of body weight reduction from baseline
Measured: Baseline (Week 0) to Week 48 and Week 60
Number of participants with treatment emergent adverse events (TEAEs) and serious adverse events (SAEs)
Measured: Up to Week 70
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 May 2026
- Study start11 May 2026
- Primary completion4 Aug 2027 (estimated)
- Study completion5 Jan 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for OverweightStudies of the same condition, open and under way.
- More trials run by PfizerThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 940 participants (actual)
Sponsor and investigators
- Lead sponsor
- Pfizer
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Pfizer CT.gov Call Center, Study director, Pfizer
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07575932
- Sponsor's protocol ID
- C6511002
- Other IDs
- SOLIS-1
- Acronym
- SOLIS-1
- Status last verified
- Oct 2026
- First submitted
- 4 May 2026
- Last updated
- 13 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: 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.