GLP-1 & weight-loss clinical trials in California
22 GLP-1 or weight-loss trials are recruiting in California as of July 14, 2026, with sites in Anaheim, Apple Valley, Beverly Hills, Costa Mesa, Covina and more. Many studies reimburse time and travel — the amount is set by each study and confirmed when you contact the team.
- A Master Protocol Study (LY900038) of Multiple Intervention-Specific-Appendices (ISAs) in Adult Participants With Obesity or Overweight
Phase 2 · ~1481 participants · NCT06143956
Studied intervention: Tirzepatide
California sites: Greenbrae, Huntington Park, Rolling Hills Estates, Walnut Creek
- A Study to Investigate Effectiveness of Tirzepatide Following Initiation of Ixekizumab in Participants With Active Psoriatic Arthritis and Overweight or Obesity in Clinical Practice (TOGETHER AMPLIFY-PsA)
Phase 4 · ~200 participants · NCT06864026
Studied intervention: Tirzepatide
California sites: Apple Valley, Covina, Huntington Beach, La Mesa, Riverside, San Diego, Santa Monica, Temecula, Tujunga, Whittier
- Tirzepatide: Reversal of Lipotoxicity and Adipose Tissue Dysfunction in Humans With Overweight/Obesity
Phase 2 · ~66 participants · NCT05912621
Studied intervention: Tirzepatide
California site: Palo Alto
- A Research Study Comparing How Well Different Doses of the Medicine NNC0519-0130 Can Reduce Kidney Damage in People Living With Chronic Kidney Disease
Phase 2 · ~465 participants · NCT06717698
Studied intervention: Semaglutide
California sites: San Dimas, San Ramon
- Tirzepatide for Alcohol Use Disorder
Phase 2 · ~42 participants · NCT06994338
Studied intervention: Tirzepatide
California site: Los Angeles
- A Research Study Comparing Different Ways of Increasing the Dose of NNC0662-0419 in Participants With Obesity
Phase 2 · ~230 participants · NCT07639021
Studied intervention: Semaglutide, Semaglutide placebo
California sites: Costa Mesa, Los Angeles
- A Study of Orforglipron (LY3502970) in Participants With Obesity or Overweight and Osteoarthritis (OA) of the Knee
Phase 3 · ~800 participants · NCT07153471
Studied intervention: Orforglipron
California sites: Huntington Beach, Thousand Oaks
- A Platform Trial for Pediatric Participants With Obesity or Overweight (LY900040)
Phase 3 · ~125 participants · NCT06672549
Studied intervention: Orforglipron
California site: Ventura
- Sit Less, Interact and Move More (SLIMM) 2 Study
Phase 2 · ~156 participants · NCT05173714
Studied intervention: Semaglutide
California site: Stanford
- Brown Adipose Tissue Activity in Response to Semaglutide Administered to Obese Subjects.
Interventional · ~20 participants · NCT05419726
Studied intervention: Semaglutide Injectable Product (not provided by the study)
California site: Los Angeles
- Efficacy and Safety of KAI-9531 Administered Once Weekly Compared With Semaglutide and Placebo in Participants Living With Obesity Who Do Not Have Diabetes
Phase 3 · ~1200 participants · NCT07284979
Studied intervention: Semaglutide
California sites: Northridge, Oceanside
- A Research Study to Look at How Two Different Doses of CagriSema and One Dose of Semaglutide Help People Living With Obesity With or Without Type 2 Diabetes Lose Weight
Phase 3 · ~2500 participants · NCT07564414
Studied intervention: Semaglutide
California sites: Escondido, La Mesa, Lincoln, Loma Linda, Los Alamitos, Northridge, Palm Springs, San Diego, Van Nuys, Walnut Creek
- A Study of Orforglipron in Female Participants With Stress Urinary Incontinence Who Have Obesity or Overweight
Phase 3 · ~1000 participants · NCT07202884
Studied intervention: Orforglipron
California sites: Los Angeles, Montebello, Tustin
- A Study to Investigate the Effectiveness of Tirzepatide (LY3298176) Following Initiation of Ixekizumab (LY2439821) in Participants With Moderate-to-Severe Plaque PsO and Obesity or Overweight in Clinical Practice (TOGETHER AMPLIFY-PsO)
Phase 4 · ~200 participants · NCT06857942
Studied intervention: Tirzepatide
California sites: Fountain Valley, Fremont, Los Angeles, Northridge
- Examination of How the Duration of Fasting and Temporary Stopping of GLP-1 Medications Affect the Amount of Food Left in the Stomach in People Using Liraglutide (Injected), Semaglutide (Taken by Mouth) or Semaglutide (Injected)
Phase 1 · ~75 participants · NCT07225816
Studied intervention: Liraglutide, Oral Semaglutide, Semaglutide
California site: Cypress
- A Study of Orforglipron (LY3502970) in Adolescent Participants With Obesity, or Overweight With Related Comorbidities
Phase 3 · ~150 participants · NCT06672939
Studied intervention: Orforglipron
California site: Ventura
- A Study of Tirzepatide in Adolescents With Obesity and Weight-Related Comorbidities (SURMOUNT-ADOLESCENTS-2)
Phase 3 · ~300 participants · NCT06439277
Studied intervention: Tirzepatide
California sites: Los Angeles, Sacramento
- Mirikizumab and Tirzepatide Administered in Adult Participants With Moderately to Severely Active Crohn's Disease and Obesity or Overweight
Phase 3 · ~290 participants · NCT06937099
Studied intervention: Tirzepatide
California sites: Anaheim, Beverly Hills, Los Alamitos, Northridge
- A Research Study on How Well Cagrilintide and CagriSema Work in Children and Adolescents With Excess Body Weight
Phase 3 · ~460 participants · NCT07253285
Studied intervention: Cagrilintide, Semaglutide, Placebo cagrilintide, Placebo semaglutide
California site: Escondido
- Mechanisms of Semaglutide Therapy in Heart Failure Patients
Phase 1, Phase 2 · ~10 participants · NCT06541509
Studied intervention: Semaglutide
California sites: Palo Alto, Stanford
- A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight and Chronic Low Back Pain
Phase 3 · ~586 participants · NCT07035093
Studied intervention: Retatrutide
California sites: Fountain Valley, Fullerton, Los Angeles, San Diego
- Mirikizumab Administered at the Same Time as Tirzepatide in Adult Participants With Moderately to Severely Active Ulcerative Colitis and Obesity or Overweight: Phase 3b Study
Phase 3 · ~350 participants · NCT06937086
Studied intervention: Tirzepatide
California sites: Anaheim, Beverly Hills, Los Alamitos, Northridge
What joining a GLP-1 trial in California actually involves
Every study above is registered on ClinicalTrials.gov, the US National Library of Medicine's public registry, and each link goes straight to that record — the one place the eligibility criteria, the schedule of visits and the contact details are kept current. A recruiting listing means the study is actively enrolling; it does not mean you are eligible until the study team screens you.
- Reimbursement is not the same as payment. Many studies cover time and travel, but the amount is set per study and confirmed by the team — treat any specific figure you see elsewhere as unverified until they tell you.
- You may receive a placebo. Most of these are randomized, so joining is not a guaranteed route to the active drug. That is worth weighing if your goal is treatment rather than contributing to the evidence.
- Trial participation is free to join and separate from a prescription. If your aim is to start a GLP-1 now, compare the cash-pay routes instead — trials are a different path with a different purpose.
Source: ClinicalTrials.gov (US National Library of Medicine), public-domain data, snapshot July 14, 2026. This is not medical advice or a recruitment service — confirm status, eligibility, and compensation on each linked ClinicalTrials.gov record and discuss any trial with your clinician.