Written by: Ellie Pranckevicius, FNP-BC, Aesthetic Nurse Practitioner & Aesthetic Injector | Facial Restoration & Regenerative Injectable Specialist, Mirror Plastic Surgery | Last updated: August 19, 2026
Key Takeaways on Retatrutide (GLP-3R) and Mirror Plastic Surgery
- Retatrutide (GLP-3R) is the first triple agonist targeting GIP, GLP-1, and glucagon receptors, now in Phase 3 trials with an FDA submission planned for Q1 2027.
- Phase 3 data show average weight loss of 19–22.6% at 80 weeks on the 12 mg dose, plus A1C reductions of about 1.5% in adults with type 2 diabetes.1
- Retatrutide carries higher gastrointestinal side-effect rates and a modest heart-rate increase compared with tirzepatide, so ongoing medical supervision is essential.
- Retatrutide remains investigational and is not FDA-approved, and purchasing from unregulated online sources carries both legal and safety risks.
- Mirror Plastic Surgery offers supervised, batch-tested GLP-3R compounding with comprehensive lab review and 24/7 concierge access, and you can schedule your personalized consultation today.
How GLP-3R Clinical Trials Evaluate Retatrutide
GLP-3R clinical trials are regulated research studies that evaluate retatrutide, a once-weekly injectable peptide that activates three metabolic receptors, GIP, GLP-1, and glucagon, to reduce appetite, increase energy expenditure, and improve glycemic control. Eli Lilly sponsors the trials across two Phase 3 programs, TRIUMPH for obesity and TRANSCEND for type 2 diabetes, with participants enrolled worldwide.
Because formal enrollment is now closed for most major studies, adults interested in supervised access to next-generation incretin peptides often benefit from a clinical consultation to review eligibility, risks, and alternatives. Schedule a consultation with Ellie for a personalized metabolic assessment.
Current Phase 3 Retatrutide Programs and What They Measure
The following table summarizes the active and recently completed Phase 3 retatrutide trials as of August 2026. TRIUMPH-1, -2, and -3 have completed their 80-week primary endpoints, while the cardiovascular and renal outcomes trial, TRIUMPH-Outcomes, will not deliver primary results until 2029, so long-term safety data remain incomplete. All data are drawn from ClinicalTrials.gov and Eli Lilly investor releases cited inline.
| Trial Name | NCT Link | Phase / Status | Primary Endpoints |
|---|---|---|---|
| TRIUMPH-1 | NCT05882045 | Phase 3 / Completed (80 weeks) | Percent change in body weight, ≥5% weight-loss responder rate |
| TRIUMPH-2 | NCT05929079 | Phase 3 / Completed (80 weeks) | Percent change in body weight, A1C reduction in adults with T2D and obesity |
| TRIUMPH-3 | NCT05882045 program | Phase 3 / Completed (80 weeks) | Percent change in body weight in adults with severe obesity (BMI ≥35) and established CVD |
| TRIUMPH-Outcomes | NCT06383390 | Phase 3 / Active, not recruiting, estimated primary completion Feb 2029 | Cardiovascular outcomes, kidney outcomes in adults with obesity |
| TRANSCEND-T2D-1 | NCT06354660 | Phase 3 / Completed, primary completion Jan 2026 | A1C reduction, weight change in 537 adults with T2D on diet and exercise alone |
Lilly’s TRIUMPH program began in 2023 and has enrolled participants across its global registrational trials. The TRANSCEND program has also enrolled participants, with additional results anticipated through 2027.
Weight-Loss and Metabolic Results from TRIUMPH Trials
Phase 3 efficacy data place retatrutide among the most potent weight-loss agents studied so far. The 19–22.6% weight-loss range cited in the key takeaways comes from two high-risk populations and shows consistent results across different cardiovascular profiles.
- TRIUMPH-2 (80 weeks, adults with T2D and obesity): retatrutide 12 mg produced an average weight loss of 49.6 lbs (20.8%) from a baseline of 106.4 kg and an A1C reduction of 1.5% from a baseline of 7.7%.1
- TRIUMPH-3 (80 weeks, adults with severe obesity and CVD): retatrutide 12 mg produced an average weight loss of 55.8 lbs (22.6%) from a baseline of 111.4 kg.1
- TRIUMPH-1 (80 weeks): retatrutide 4 mg achieved an average weight loss of 47.2 lbs (19.0%) from a baseline of 112.7 kg, and a pre-specified 104-week extension in participants with BMI ≥35 on 12 mg reached an average loss of 85.0 lbs (30.3%).1
- In Phase 2 data, 100% of participants on 8 mg or 12 mg achieved at least 5% weight loss and 93% on 12 mg achieved at least 10% weight loss at 48 weeks.1
These results prompted Lilly’s leadership to describe retatrutide as a potential cornerstone of future cardiometabolic therapy. Kenneth Custer, Ph.D., executive vice president and president of Lilly Cardiometabolic Health, stated: “Across four positive Phase 3 studies, retatrutide has shown powerful efficacy, and we believe it could be an important future tool in the management of cardiometabolic health.”
Adults who want to understand how these numbers relate to their own labs and history can benefit from a structured review. Request a lab review and protocol discussion with Ellie to explore your options.
GLP-3R vs. Tirzepatide Side Effects in Recent Trials
No published head-to-head clinical trial directly compares retatrutide and tirzepatide. Available comparisons rely on cross-trial analyses from the retatrutide Phase 2 obesity trial (N=338, 48 weeks) and the SURMOUNT-1 tirzepatide trial (N=2,539, 72 weeks), which require cautious interpretation because of differences in duration, population size, and protocol. Phase 3 parallel-trial data provide a more recent, though still indirect, view.
The following rates are drawn from separate Phase 3 trials with different participant populations and study designs, so they are not definitive direct comparisons. The table highlights that retatrutide shows consistently higher gastrointestinal side-effect rates and a slightly larger heart-rate increase, which reinforces the need for close medical follow-up.
| Side Effect | Retatrutide 12 mg (Phase 3) | Tirzepatide 15 mg (Phase 3) |
|---|---|---|
| Nausea | 43% | 31% |
| Diarrhea | 33% | 23% |
| Vomiting | 21% | 12% |
| Constipation | 25% | 12% |
| Dysesthesia (abnormal skin sensation) | 21% | Not reported |
| Resting heart-rate increase | ~+6 bpm | +2–5 bpm |
Retatrutide’s adverse-event rates and discontinuations increased with higher doses, with Phase 3 data showing discontinuation due to adverse events at 4.1% (4 mg), 6.9% (9 mg), and 11.3% (12 mg) versus 4.9% on placebo. The added glucagon receptor activity of retatrutide is predicted to increase both energy expenditure and certain side-effect surfaces, including a modestly larger gastrointestinal burden and heart-rate elevation compared with tirzepatide’s dual GIP and GLP-1 mechanism.
Retatrutide trials excluded participants with a history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2, which aligns with precautions for tirzepatide. In Phase 2 trials, pancreatitis occurred in about 0.4% of retatrutide participants and gallbladder problems in about 1.1%.
Regulatory Status: Is GLP-3R FDA Approved?
NOT FDA-APPROVED: As noted in the key takeaways, retatrutide has not received U.S. FDA approval for any indication as of August 2026. An FDA spokesperson confirmed that retatrutide “has not been found safe or effective for any condition” and “cannot be manufactured or distributed except for investigational use.” Eli Lilly plans to submit a Biologics License Application to the FDA in Q1 2027, with a potential decision in late 2027 or early 2028.
Risks of Buying GLP-3R Retatrutide Online
Purchasing retatrutide from online retailers carries significant legal and medical risks. The FDA has sent warning letters to companies advertising retatrutide, and some of those companies continued offering the drug online afterward. Legal actions involving the sale and prescription of retatrutide have already occurred.
State-level enforcement has also escalated:
- Ohio’s Board of Pharmacy has taken enforcement action against multiple pharmacies and clinics providing retatrutide.
- Utah’s Department of Professional Licensing has issued guidance regarding the prescribing of retatrutide.
- Alabama’s Medical Board issued a warning to physicians against prescribing research-grade medications such as retatrutide.
- The FDA states there is no legal justification for compounding pharmacies to produce retatrutide, a position communicated directly to state medical boards and pharmacy associations.
Buying from unverified online sources also means no third-party batch testing, no dosing oversight, and no screening for contraindications. The regulatory environment around retatrutide continues to evolve, and the risks of unsupervised sourcing remain both medical and legal.
How to Enroll in Retatrutide Trials in 2026
Formal trial enrollment for the major TRIUMPH and TRANSCEND studies is no longer open. The TRIUMPH-Outcomes trial (NCT06383390) is currently active but not recruiting as of July 2026. Adults who want to pursue a research pathway can follow the standard steps below for any future or ancillary retatrutide studies.
- Search ClinicalTrials.gov using the term “retatrutide” and filter by “Recruiting” status and your geographic region.
- Review the eligibility criteria carefully, because most TRIUMPH trials required BMI of at least 27 with at least one weight-related comorbidity, or BMI of at least 35 for the severe-obesity cohorts.
- Contact the listed study coordinator at the nearest trial site to request a pre-screening call.
- Obtain and review the informed consent document before any screening visit.
- Complete required screening labs and physical assessments at the trial site.
- If enrolled, follow the site’s dose-escalation schedule and attend all protocol-specified follow-up visits.
Adults who do not qualify for or cannot access an active trial often consider medically supervised compounding through a licensed practitioner, which serves as an alternative pathway and is discussed in the next section.
Supervised GLP-3R Compounding at Mirror Plastic Surgery
Mirror Plastic Surgery offers a concierge GLP-3R compounding service led by Ellie Pranckevicius, FNP-BC. This pathway serves adults who have already explored GLP-1 therapies and want evidence-informed, supervised access to next-generation incretin-class peptides without the risks of unregulated online sourcing.
The Mirror Plastic Surgery process differs from online retailers in several concrete ways:
- In-depth lab review: Ellie reviews thyroid, liver, kidney, diabetes markers, and hormone panels before any protocol begins. If labs are not available, she orders them.
- Batch-tested sourcing: Peptides come from reputable compounding providers with documented batch testing for purity and accurate dosage.
- Personalized dose escalation: Protocols are tailored to individual physiology, health history, and goals, not a single standard starting dose.
- 24/7 concierge access: Patients have direct text access to Ellie throughout their protocol, including reconstitution guidance, side-effect management, and refill coordination.
- Remote availability: The full process, including consultation, prescription, and shipping, is available in-person in St. Petersburg and Tampa or remotely across the United States.
Start your supervised GLP-3R assessment by booking a consultation with Ellie.
Long-Term Maintenance Expectations with GLP-3R
Controlled safety data up to 104 weeks, about 24 months, of continuous retatrutide use have been reported from the TRIUMPH-1 trial extension. Long-term cardiovascular, renal, and cancer safety data will come from the ongoing TRIUMPH-Outcomes trial (NCT06383390), with an estimated primary completion of February 2029.
Based on available Phase 2 and Phase 3 data, realistic long-term expectations fall into three themes, tolerability, efficacy thresholds, and outcomes after stopping therapy. Understanding each theme helps patients set goals and recognize when protocol changes may be needed.
- Gastrointestinal adverse events such as nausea, diarrhea, and vomiting are predominantly mild to moderate, dose-related, and usually resolve within 4–8 weeks as patients adapt to therapy.1
- Therapy should be discontinued if weight loss remains below 5% after 24 weeks on a therapeutic dose of at least 4 mg, which defines the efficacy threshold below which continued treatment is not justified.1
- Weight regain after discontinuation is expected, consistent with other GLP-1 drugs, although the rate and extent have not been characterized in retatrutide trials, so patients need a maintenance plan from the start.1
- No published retatrutide trial has reported detailed body-composition analysis separating fat loss from lean-mass loss, and lean-mass loss is estimated at 25–40% of total weight lost based on the broader GLP-1 class, which supports including resistance training in any plan.1
- Researchers continue monitoring potential cardiovascular effects and pancreatic complications, and additional Phase 3 TRIUMPH trial results are expected through 2026, so long-term safety data will keep evolving.
Sustained results require a maintenance protocol. Ellie Pranckevicius approaches GLP-3R therapy the way a clinician approaches any chronic metabolic condition, with ongoing lab monitoring, dose adjustments, and a long-term plan that adapts as your physiology changes.
Frequently Asked Questions About GLP-3R at Mirror Plastic Surgery
What is the difference between GLP-1 and GLP-3R (retatrutide)?
GLP-1 receptor agonists such as semaglutide activate a single receptor pathway to reduce appetite and improve insulin secretion. Retatrutide, referred to as GLP-3R in the compounding context, activates three receptors, GIP, GLP-1, and glucagon. The glucagon component adds an energy-expenditure effect that GLP-1 monotherapy does not provide, which helps explain why Phase 3 trials show higher weight-loss percentages than earlier-generation agents. The tradeoff is a broader side-effect profile, especially gastrointestinal symptoms and a modest increase in resting heart rate, so medical supervision and individualized dose escalation remain essential.
Can I access retatrutide outside of a clinical trial?
Retatrutide is not FDA-approved and cannot be legally compounded or distributed outside an officially sanctioned clinical trial under current federal guidance. The FDA has issued warning letters to companies selling it online, and active federal and state enforcement actions are ongoing. Mirror Plastic Surgery’s GLP-3R compounding service uses next-generation incretin-class peptides sourced from batch-tested compounding providers under medical supervision, which is a fundamentally different model from unregulated online retailers. Ellie Pranckevicius conducts a full lab review and medical history evaluation before starting any protocol to confirm that the approach fits your individual health profile.
How does Mirror Plastic Surgery’s GLP-3R service differ from a telehealth weight-loss clinic?
High-volume telehealth platforms typically rely on standardized protocols with limited one-on-one time. Mirror Plastic Surgery’s model is built on concierge medicine, and Ellie Pranckevicius spends up to an hour in consultation, reviews comprehensive lab panels, and creates a custom protocol based on your specific metabolic markers, health history, and goals. Patients have direct 24/7 text access to Ellie throughout their protocol, not a call center or automated refill system. If a surgical complement is ever appropriate, Dr. Akash Chandawarkar, a Harvard-educated and Johns Hopkins-trained plastic surgeon, is available within the same practice.
What happens if I stop GLP-3R therapy?
Based on the broader incretin class, weight regain after discontinuation is expected. The rate and extent specific to retatrutide have not yet been characterized in published trials. Metabolic benefits, including improvements in A1C, lipid panels, and blood pressure, are also likely to diminish without a maintenance protocol. Ellie designs long-term maintenance plans from the outset, including periodic lab monitoring and dose adjustments, to help patients sustain the results they achieve during active therapy.
Is GLP-3R compounding safe for people with cardiovascular conditions?
Retatrutide’s glucagon receptor activity produces a dose-dependent increase in resting heart rate that peaked at about +6.7 bpm at the 12 mg dose in Phase 2 data and then declined. The TRIUMPH-3 trial specifically enrolled adults with severe obesity and established cardiovascular disease, and the long-term TRIUMPH-Outcomes trial is evaluating cardiovascular and renal endpoints through 2029. For any patient with a cardiac history, a thorough pre-treatment evaluation, including relevant labs and a review of current medications, is essential before starting any incretin-class peptide. Ellie conducts this evaluation as a standard part of the Mirror Plastic Surgery consultation process.
Contact Mirror Plastic Surgery for GLP-3R Guidance
Mirror Plastic Surgery is located in St. Petersburg, Florida, and serves patients in-person throughout the Tampa Bay area and remotely across the United States, including Hawaii and Alaska.
- Address: 780 4th Ave S, St. Petersburg, FL 33701
- Phone: 727-361-6515
- Email: hello@mirrorplasticsurgery.com
- Instagram: @mirrorplasticsurgery | @dr.akashplasticsurgery | @perfectlyplastics
Disclaimer: The information in this article is for educational purposes only and does not constitute medical advice. Retatrutide is an investigational drug that has not been approved by the U.S. FDA for any indication as of the date of publication. Consult a licensed healthcare provider before starting any peptide therapy.
Disclaimer: Mirror Plastic Surgery’s peptide therapies, including GLP-3R compounding, are not FDA-regulated. All protocols begin only after a comprehensive medical evaluation, including lab review, conducted by a board-certified nurse practitioner. Individual results vary.
1 Results may vary from person to person. Editorial content, before and after images, and patient testimonials do not constitute a guarantee of specific results.
Peptide therapy is intended for wellness and optimization purposes and is not prescribed to diagnose, treat, cure, or prevent disease unless specifically stated. Many peptides are not FDA-approved and may be used off-label. Some have limited long-term safety data, with a potential for unknown risks, complications, or desensitization with prolonged use.
