A new Phase 3 clinical trial is examining retatrutide — the investigational triple agonist targeting GLP-1, GIP, and glucagon receptors simultaneously — in a patient population that has not been the focus of prior large-scale obesity medication trials: adults living with obesity or overweight who also experience chronic low back pain. The full study name is A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight and Chronic Low Back Pain, registered on ClinicalTrials.gov under identifier NCT07035093.
This trial represents a meaningful expansion of the retatrutide Phase 3 program beyond straightforward weight reduction endpoints. Chronic low back pain is one of the most prevalent and disabling conditions in the world, and excess body weight is a well-established driver of both its onset and its severity. By targeting this specific comorbidity, the trial is asking a clinically important question: does the substantial weight loss produced by retatrutide translate into measurable relief for patients whose pain burden is directly compounded by excess adiposity?
Retatrutide — commonly referred to as reta in patient communities, and sometimes called a "triple G" agonist in online forums — has already generated landmark Phase 3 data through the TRIUMPH-4 trial, which reported a mean weight loss of 28.7% over 68 weeks at the 12mg maintenance dose. That figure is the highest ever recorded in a Phase 3 obesity trial. The chronic low back pain trial adds a layer of clinical specificity, probing whether those weight loss outcomes carry meaningful functional and pain-related benefits in a highly burdened subpopulation.
As of July 23, 2026, the trial's status on ClinicalTrials.gov transitioned from actively enrolling to closed enrollment. In plain clinical terms, this means the study has finished signing up participants — the cohort is full — but the trial itself is still running. Enrolled participants are continuing their assigned treatment protocols, data are being collected, and the research team is actively monitoring outcomes.
This is a routine and expected milestone in any well-conducted Phase 3 program. Reaching target enrollment on schedule is actually a positive signal: it reflects strong site activation, adequate patient interest, and operational execution by Eli Lilly and its clinical partners. The shift to closed enrollment does not indicate any safety concern, regulatory hold, or change in the study's scientific objectives.
For members of the public who were hoping to join this specific trial, however, it does mean that direct participation is no longer possible. The window for enrollment has closed.
According to ClinicalTrials.gov, the primary completion date for NCT07035093 is September 2027. This is the date by which primary endpoint data collection is expected to be finished — meaning the last enrolled participant will have completed their core assessment period by that time.
Following primary completion, the research team will conduct data analysis, and results are typically submitted for peer-reviewed publication and regulatory review. Given that the peer-reviewed Phase 3 publication from TRIUMPH-4 was still pending as of April 2026, the research and publication pipeline for the full TRIUMPH program remains active and ongoing.
The table below places NCT07035093 in context alongside other key retatrutide and comparator trial milestones:
| Trial | Drug | Phase | Duration | Mean Weight Loss (Top Dose) | Key Focus |
|---|---|---|---|---|---|
| Phase 2 (NCT04881760) | Retatrutide | Phase 2 | 48 weeks | ~24.2% (12mg) | Obesity without T2D |
| TRIUMPH-4 | Retatrutide | Phase 3 | 68 weeks | 28.7% (12mg) | Obesity |
| NCT07035093 (TRIUMPH) | Retatrutide | Phase 3 | Active; primary completion Sept 2027 | Pending | Obesity + Chronic Low Back Pain |
| SURMOUNT-1 | Tirzepatide | Phase 3 | 72 weeks | 20.9% (15mg) | Obesity without T2D |
| STEP-1 | Semaglutide | Phase 3 | 68 weeks | ~14.9% (2.4mg) | Obesity without T2D |
Completing enrollment in a Phase 3 trial is a necessary step on the regulatory pathway, but it is one of several. As of April 2026, Eli Lilly had not yet filed a New Drug Application (NDA) with the FDA for retatrutide, and no FDA approval timeline had been publicly confirmed. The TRIUMPH program — which includes multiple Phase 3 trials across different patient populations — must generate sufficient safety and efficacy data before an NDA submission can occur.
The chronic low back pain trial adds important breadth to that regulatory package. Obesity is increasingly understood as a disease with systemic downstream consequences, and musculoskeletal burden is among the most common. If NCT07035093 demonstrates that retatrutide's weight reduction translates into clinically meaningful pain relief and functional improvement, it could support an expanded label indication — or at minimum, strengthen the overall benefit-risk profile presented to regulators.
The Phase 2 data published in the New England Journal of Medicine in 2023 already established a compelling efficacy and safety foundation. At the 8mg dose, 100% of participants achieved at least 5% weight loss at 48 weeks; at 12mg, 48% of participants lost 25% or more of their body weight. Cardiometabolic markers also improved substantially — triglycerides fell by up to 34.0% at 24 weeks, and LDL cholesterol dropped by up to 16.9%. The TRIUMPH-4 Phase 3 trial extended those findings into a larger population with an even more striking headline result. Each completed trial enrollment brings the broader program one step closer to the regulatory finish line.
Enrollment in NCT07035093 is now closed, and no new participants can be added to this specific trial. For individuals hoping to participate in active retatrutide research, it is worth checking ClinicalTrials.gov periodically, as the broader TRIUMPH Phase 3 program includes multiple studies that may have different enrollment statuses over time.
For those experiencing the frustrating interplay of significant excess weight and chronic low back pain — dealing with limited mobility, persistent discomfort, and what many patients describe as relentless food noise that makes dietary change feel nearly impossible — the progress being made in trials like this one represents a genuinely meaningful scientific advance. A medication class capable of producing nearly 29% mean weight loss in a Phase 3 setting, while also potentially addressing weight-related musculoskeletal pain, would represent a qualitatively different therapeutic tool than anything currently available.
The path to FDA approval takes time, and retatrutide remains an investigational compound — it is not yet approved or available for prescription use. In the meantime, staying informed is one of the most useful things a patient can do. glp3md.com maintains a waitlist for individuals who want to be among the first to learn about retatrutide access as the regulatory landscape evolves. Joining the waitlist at https://www.glp3md.com costs nothing and carries no obligation. Please note: joining the waitlist does not guarantee access to retatrutide, a prescription, or any form of treatment — retatrutide is not FDA-approved, and no promises about medication availability can be made. What it does offer is timely, clinically accurate information delivered as this field moves forward — so that when meaningful access opportunities arise, informed patients are ready.
Join the waitlist for priority access to a prescribing physician when retatrutide receives FDA approval.
Join the WaitlistThis article is for educational purposes only and does not constitute medical advice. Retatrutide is an investigational drug and is not FDA approved as of publication. Clinical data referenced is from publicly available trial publications. Consult a qualified healthcare provider before making any treatment decisions.