Current Status
- Phase 3 trials ongoing: Eli Lilly's TRIUMPH program includes 4 large trials testing retatrutide in obesity and type 2 diabetes populations[3][4]
- First results expected 2025: TRIUMPH-4 data accelerated to 2025 per February 2025 company announcement[2]
- NDA submission projected: Late 2025 - Q1 2026 (analyst projection, not officially confirmed by Eli Lilly)
- FDA approval projected: Late 2026 - Mid 2027 (analyst estimate based on typical review timelines; actual timing depends on trial results and review type)
24.2% weight loss (NEJM 2023)
TRIUMPH trials in progress
Projected filing to FDA
6–12 month review period
Projected approval date
Phase 2 Results
Retatrutide's Phase 2 trial results, published in the New England Journal of Medicine (June 2023), demonstrated record-breaking efficacy:[1]
- 24.2% weight loss at 48 weeks with the 12mg weekly dose (vs 2.1% with placebo)[1]
- Highest efficacy ever reported for a single-agent obesity medication[1]
- Clear dose-response: 1mg (-8.7%), 4mg (-17.1%), 8mg (-22.8%), 12mg (-24.2%)[1]
- 50% of participants achieved ≥25% weight loss; 25% achieved ≥30%[1]
- Cardiovascular benefits: 26.9% reduction in non-HDL cholesterol[1]
Context: This exceeds tirzepatide's 22.5% weight loss (SURMOUNT-1)[6] and semaglutide's 14.9% (STEP 1),[7] positioning retatrutide as a potential best-in-class obesity medication if Phase 3 results replicate Phase 2 efficacy.
Phase 3 Program
The TRIUMPH (TRIple-hormone receptor agonist for the treatment of obesity and related coMorbidities PH) program is Eli Lilly's comprehensive Phase 3 program testing retatrutide across diverse populations:
| Trial | Population | Enrollment | Duration | Expected Results |
|---|---|---|---|---|
| TRIUMPH-1 NCT05929066 | Obesity (no diabetes) | 2,300 | 80 weeks | May 2026 |
| TRIUMPH-2 NCT05929079 | Type 2 diabetes + obesity | 1,000 | 89 weeks | May 2026 |
| TRIUMPH-3 NCT05931367 | Obesity + cardiovascular disease | 1,800 | 113 weeks | Feb 2026 |
| TRIUMPH-4 NCT05931367 | Obesity + osteoarthritis | TBD | 68 weeks | 2025 (accelerated) |
Accelerated Timeline: In February 2025, Eli Lilly announced that TRIUMPH-4 results would be available "in 2025, earlier than originally planned."[2] This may be the first Phase 3 readout.
Why It Matters: These registrational trials will determine whether retatrutide's record-breaking Phase 2 efficacy (24.2% weight loss) translates to larger, more diverse populations. Positive results are required for FDA approval.
NDA Submission
What is an NDA?
A New Drug Application (NDA) is the formal request to the FDA to approve a new drug for marketing in the United States. It's a comprehensive package containing:
- Results from all clinical trials (Phase 1, 2, and 3)
- Manufacturing and quality control processes
- Proposed drug labeling and patient information
- Safety monitoring plans
Projected Timeline
Late 2025 - Q1 2026
Estimated NDA filing
Projected based on Phase 3 completion dates (2025-2026). Eli Lilly has NOT announced an official filing timeline.
Key Assumptions
- TRIUMPH trials complete successfully
- No unexpected safety concerns
- Typical 3-6 month lag between final trial data and NDA filing
- Eli Lilly prioritizes obesity indication first
Important: This is a projection, not a confirmed date. Actual NDA filing depends on Phase 3 results, FDA pre-submission meetings, and Eli Lilly's regulatory strategy.
FDA Review Process
Once Eli Lilly submits the NDA, retatrutide will move through a structured FDA review process:
NDA Submission
Eli Lilly submits complete application with all clinical trial data, manufacturing details, and proposed labeling.
FDA Review Period
FDA scientists evaluate:
- Clinical trial efficacy and safety data
- Manufacturing quality and controls
- Proposed labeling and patient information
- Risk-benefit profile
PDUFA Date Decision
By the PDUFA date (FDA's target action deadline), the FDA must issue one of three decisions:
- Approval: Drug can be marketed
- Complete Response Letter: Issues need to be addressed before approval (delays by 6-12+ months)
- Extend review: More time needed (rare)
Priority Review Status
Standard Review (10-12 months)
Most likely for retatrutide
- For drugs that offer advances over existing therapies
- Typical for obesity medications
- PDUFA clock: 10-12 months from acceptance
Priority Review (6 months)
Possible but not guaranteed
- Requires "significant improvement" over existing therapies
- 24.2% vs tirzepatide's 22.5% may qualify
- Cuts review time in half (6 months)
- Decision made AFTER NDA filing
Fast Track & Breakthrough Therapy Status
Current Status: No Fast Track or Breakthrough Therapy designation has been publicly announced for retatrutide as of January 2025.[5]
Context: Tirzepatide (Eli Lilly's dual GIP/GLP-1 agonist) received Fast Track for obesity in October 2022.[6] It's possible Eli Lilly is pursuing similar designations for retatrutide but has not disclosed it publicly.
Approval Scenarios
Best Case: Late 2026
Requirements:
- TRIUMPH trials match Phase 2 efficacy (24.2%)
- No unexpected safety signals
- NDA filed Q4 2025
- FDA grants Priority Review (6 months)
- No Advisory Committee delays
Approval: Late 2026
Most Likely: Mid 2027
Realistic Expectations:
- TRIUMPH shows good results (18-22% weight loss)
- Safety consistent with Phase 2
- NDA filed Q1 2026
- FDA assigns Standard Review (10-12 months)
- Advisory Committee meeting (adds 3-6 months)
Approval: Mid 2027 (Q2 2027)
Delayed: 2028+
Potential Roadblocks:
- Phase 3 efficacy lower than expected (18-20%)
- Unexpected safety concerns
- FDA issues Complete Response Letter
- Manufacturing or quality control issues
- Advisory Committee votes against approval
Approval: 2028 or later
Critical Disclaimer: These timelines are PROJECTIONS based on historical drug development patterns, NOT official Eli Lilly or FDA announcements. Actual approval timing depends entirely on Phase 3 results, FDA review findings, and potential regulatory issues.
Post-Approval Timeline
Month 1-3: Immediate Post-Approval
- Manufacturing scale-up and pharmacy distribution
- Launch pricing announced (estimated $1,000-1,500/month)
- Sales force training and physician education
- Patient savings programs and copay cards launched
Month 3-6: Insurance Coverage
- Commercial insurers make formulary decisions
- Prior authorization requirements established
- Step therapy policies (may require trying semaglutide/tirzepatide first)
- Medicare Part D coverage determinations (3-6 months)
Month 6-12: Broader Access
- Real-world effectiveness data collection
- Post-marketing surveillance for rare side effects
- Insurance coverage expands as evidence builds
- Potential label expansions (cardiovascular indication)
Key Barriers to Access: High cost ($1,000-1,500/month without insurance), prior authorization requirements, step therapy (may need to try cheaper GLP-1s first), and insurance exclusions for obesity medications.
FAQs
Retatrutide is currently in Phase 3 clinical trials (TRIUMPH program). Based on typical FDA timelines:
- Phase 3 Completion: 2025-2026 (TRIUMPH-4 results expected in 2025)
- NDA Filing (projected): Late 2025 - Q1 2026
- FDA Review: 6 months (Priority Review) or 10-12 months (Standard Review)
- Approval (projected): Late 2026 - Mid 2027
Important: These are projections, not official announcements from Eli Lilly or the FDA. Actual timing depends on Phase 3 results and FDA review findings.
No. Retatrutide is investigational and NOT FDA-approved. It cannot be prescribed or purchased through any legitimate pharmacy.
How to Access Retatrutide Today:
The ONLY way to access retatrutide is through enrollment in Phase 3 clinical trials:
- TRIUMPH-1 (obesity, no diabetes) - NCT05929066
- TRIUMPH-2 (type 2 diabetes + obesity) - NCT05929079
- TRIUMPH-3 (obesity + cardiovascular disease) - NCT05931367
- TRIUMPH-4 (obesity + osteoarthritis) - NCT05931367
Visit ClinicalTrials.gov and search "retatrutide" to see if you meet eligibility criteria for any recruiting trials.
Warning: Do not purchase "retatrutide" from online vendors or compounding pharmacies. These products are not legitimate and may be dangerous.
PDUFA stands for Prescription Drug User Fee Act. The PDUFA date is the FDA's target deadline to complete review of a New Drug Application (NDA).
How It Works:
- Eli Lilly submits NDA to FDA
- FDA has 60 days to decide whether to accept the application
- If accepted, FDA assigns a PDUFA date (target action date)
- PDUFA date is typically:
- 10-12 months after acceptance for Standard Review
- 6 months after acceptance for Priority Review
Important: The PDUFA date is a goal, not a guarantee. FDA may approve before the PDUFA date, extend the review, or issue a Complete Response Letter requesting more information.
Retatrutide Status: No PDUFA date has been assigned yet (NDA not yet filed).
Priority Review is an FDA designation that cuts the review time from 10-12 months to 6 months.
Criteria for Priority Review:
- Drug must treat a serious condition
- Drug must offer a "significant improvement" in safety or effectiveness over existing therapies
Will Retatrutide Get Priority Review?
Unknown. Priority Review is determined AFTER NDA filing, not before.
Factors in Favor:
- 24.2% weight loss (Phase 2) vs tirzepatide's 22.5% = potential "significant improvement"
- Obesity affects 40%+ of U.S. adults (serious public health issue)
- Tirzepatide received Fast Track for obesity (precedent)
Factors Against:
- Effective treatments already exist (tirzepatide, semaglutide)
- FDA may not consider 24.2% vs 22.5% as "significant" (only ~2% difference)
Bottom Line: Possible but not guaranteed. We'll know when FDA assigns the PDUFA date after NDA filing.
No. Eli Lilly has not publicly announced Fast Track designation for retatrutide as of January 2025.
What is Fast Track?
Fast Track is an FDA program to expedite development and review of drugs treating serious conditions with unmet medical need.
Benefits:
- More frequent FDA meetings during development
- Eligibility for Accelerated Approval and Priority Review
- Rolling NDA submission (submit sections as completed)
Comparator: Tirzepatide (Eli Lilly's dual GIP/GLP-1 agonist) received Fast Track for obesity in October 2022.
It's possible Eli Lilly is pursuing Fast Track for retatrutide but has not disclosed it publicly.
If retatrutide is approved, here's the typical timeline to patient access:
Month 1-3 (Immediate Post-Approval):
- Manufacturing scale-up and pharmacy distribution
- Pricing announced (estimated $1,000-1,500/month)
- Sales representatives begin physician education
- Patient savings programs and copay cards launched
Month 3-6 (Insurance Coverage Decisions):
- Commercial insurers make formulary placement decisions
- Prior authorization requirements established
- Step therapy policies (may require trial of cheaper GLP-1s first)
- Medicare Part D coverage determinations
Month 6-12 (Broader Access):
- Real-world effectiveness data collection
- Post-marketing surveillance for rare side effects
- Insurance coverage expands as evidence builds
- Potential label expansions (cardiovascular indication)
Key Barriers: High cost ($1,000+/month without insurance), prior authorization requirements, step therapy, and insurance exclusions.
Citations
- Peer-Reviewed Jastreboff AM, Kaplan LM, Frías JP, et al. "Triple–Hormone-Receptor Agonist Retatrutide for Obesity — A Phase 2 Trial." N Engl J Med. 2023;389(6):514-526. Link
- Press Release CNBC. "Eli Lilly to release late-stage data on next-generation weight loss drug retatrutide in 2025, earlier than expected." February 6, 2025. Link
- Clinical Trial Registry ClinicalTrials.gov. "A Study of Retatrutide (LY3437943) in Participants Who Have Obesity or Overweight (TRIUMPH-1)." NCT05929066. Link
- Clinical Trial Registry ClinicalTrials.gov. "A Study of Retatrutide (LY3437943) in Participants With Type 2 Diabetes Who Have Obesity or Overweight (TRIUMPH-2)." NCT05929079. Link
- FDA Document U.S. Food and Drug Administration. "Fast Track, Breakthrough Therapy, Accelerated Approval, Priority Review." Link
- Regulatory History Drugs.com. "Mounjaro (tirzepatide) FDA Approval History." Link
- Regulatory History Drugs.com. "Wegovy (semaglutide) FDA Approval History." Link
Last updated October 6, 2026
Disclaimer
The information on this page is for educational and informational purposes only and is not intended as medical advice. Honest Care does not provide medical diagnosis, treatment, or individualized recommendations. Always seek the advice of your physician or other qualified healthcare professional regarding any medical condition or treatment.
While this content has been reviewed for accuracy and balance, new evidence may emerge after publication. Drug availability, indications, and insurance coverage can change over time. Honest Care makes no warranties as to completeness or currentness of the information and is not responsible for decisions made based on this content.