If you thought Ozempic and Mounjaro were impressive, wait until you see the data on retatrutide. This triple-action weight loss drug from Eli Lilly is producing the most dramatic results ever seen in obesity clinical trials — and it's heading toward approval. Here's what Southeast Asian patients need to know.

Key Takeaways

  • Retatrutide is a triple agonist targeting GLP-1, GIP, and glucagon receptors — the first of its kind
  • Phase 2 results: 28.7% body weight loss at the highest dose over 48 weeks — more than any existing medication
  • Phase 3 trials are underway; FDA approval estimated around 2027
  • Malaysia availability: Estimated 2028–2029 following FDA/EMA approval and NPRA registration
  • Developed by Eli Lilly (same company behind Mounjaro/tirzepatide)

Medical Disclaimer: Retatrutide is an investigational drug that has not yet been approved by any regulatory authority. This article is for informational purposes only and reflects data from published clinical trials. Do not attempt to obtain or use unapproved medications.

What Is Retatrutide?

Retatrutide (development code LY3437943) is a triple hormone receptor agonist being developed by Eli Lilly. While current medications target one pathway (Ozempic → GLP-1) or two pathways (Mounjaro → GLP-1 + GIP), retatrutide targets three:

  1. GLP-1 (glucagon-like peptide-1) — reduces appetite, slows gastric emptying, improves insulin secretion. The proven mechanism behind Ozempic and Wegovy.
  2. GIP (glucose-dependent insulinotropic polypeptide) — enhances insulin sensitivity, improves fat metabolism. The second mechanism in Mounjaro.
  3. Glucagon — the third and entirely new component. Glucagon receptor activation increases energy expenditure (calories burned), promotes fat breakdown (lipolysis), and may reduce liver fat.

Why the Glucagon Component Is a Game-Changer

The addition of glucagon receptor agonism is what makes retatrutide fundamentally different from everything that came before. Here's why it matters:

  • Increased energy expenditure: GLP-1 and GIP primarily work by reducing food intake. Glucagon actually increases the calories your body burns — addressing both sides of the energy balance equation
  • Enhanced fat burning: Glucagon promotes lipolysis (the breakdown of stored fat) and hepatic fat oxidation, potentially targeting visceral and liver fat more effectively
  • NAFLD/MASH potential: Early data suggests retatrutide may dramatically reduce liver fat, making it a potential treatment for non-alcoholic fatty liver disease — a condition affecting an estimated 25–30% of the Malaysian adult population
  • Metabolic rate preservation: One concern with weight loss drugs is metabolic adaptation (your body burns fewer calories as you lose weight). Glucagon activation may partially counteract this

In simple terms: Ozempic makes you eat less. Mounjaro makes you eat less and metabolise better. Retatrutide makes you eat less, metabolise better, and burn more energy. It's a triple threat.

The Phase 2 Trial Results That Stunned the World

The Phase 2 trial results for retatrutide, published in the New England Journal of Medicine in 2023, sent shockwaves through the obesity medicine community. The study enrolled 338 adults with obesity (BMI ≥30 or ≥27 with comorbidities) and tested multiple doses over 48 weeks.

Weight Loss Results by Dose

DoseMean Weight Loss at 48 Weeks% Losing ≥15%
1 mg8.7%29%
4 mg (escalated)17.1%67%
4 mg (fixed)22.8%75%
8 mg (escalated)22.1%81%
8 mg (fixed)25.4%83%
12 mg (escalated)24.2%93%
12 mg28.7%~90%
Placebo2.1%

Let those numbers sink in. At the 12 mg dose, participants lost nearly 29% of their body weight in under a year. For a 100 kg person, that's almost 29 kg — approaching the results of bariatric surgery without going under the knife.

How This Compares to Existing Drugs

DrugMechanismBest Trial Weight Loss
Ozempic/Wegovy (semaglutide)GLP-1~15% (STEP 1)
Mounjaro (tirzepatide)GLP-1 + GIP~22.5% (SURMOUNT-1)
RetatrutideGLP-1 + GIP + Glucagon~28.7% (Phase 2)

Each generation has delivered a meaningful leap in efficacy. Retatrutide represents the most dramatic weight loss ever achieved by a pharmaceutical intervention in clinical trials.

Phase 3 Trials and Approval Timeline

Eli Lilly launched the Phase 3 clinical programme for retatrutide in 2024, known as the TRIUMPH trial series. These large-scale studies are evaluating:

  • TRIUMPH-1: Weight management in adults with obesity (non-diabetic)
  • TRIUMPH-2: Weight management in adults with obesity and type 2 diabetes
  • TRIUMPH-3: Cardiovascular outcomes
  • TRIUMPH-4: MASH (metabolic dysfunction-associated steatohepatitis) — formerly known as NASH
  • TRIUMPH-5: Obstructive sleep apnoea

Expected Timeline

MilestoneEstimated Timing
Phase 3 data readoutLate 2026 – Early 2027
FDA submissionMid 2027
FDA approval (US)Late 2027 – Early 2028
EMA approval (Europe)2028
NPRA registration (Malaysia)2028–2029 (estimate)
Clinic availability in Malaysia2029 (optimistic) – 2030

These timelines could shift based on trial results, regulatory review speed, and Eli Lilly's submission strategy. Malaysia's NPRA has historically been relatively efficient at reviewing drugs that have already received FDA and EMA approval, so the gap may be shorter than for some other countries.

What Might Retatrutide Cost in Malaysia?

Since retatrutide hasn't been approved yet, pricing is speculative. However, we can make educated estimates based on existing patterns:

  • Ozempic (single agonist): RM800–1,800/month in Malaysia
  • Mounjaro (dual agonist): RM1,088–3,000/month in Malaysia
  • Retatrutide (triple agonist): Likely RM2,000–4,000+/month at launch

Eli Lilly has not indicated pricing. New-to-market drugs typically command a premium, particularly when they offer demonstrably superior efficacy. Prices may decrease as manufacturing scales and competition increases.

Compare current options at our Weight Loss Injection Prices Malaysia page — we'll update it when retatrutide pricing becomes available.

Side Effects: What We Know So Far

Phase 2 data showed a side effect profile similar to existing GLP-1 medications, though with some nuances related to the glucagon component:

Common Side Effects

  • Nausea — reported by ~25% of participants; mostly during dose escalation
  • Diarrhoea — more prevalent than with semaglutide alone
  • Vomiting
  • Constipation
  • Decreased appetite

Glucagon-Related Effects to Watch

  • Increased heart rate: A modest increase in resting heart rate was observed, consistent with glucagon's stimulatory effects. Phase 3 trials are monitoring cardiovascular safety closely
  • Hepatic effects: While glucagon activation may benefit fatty liver, liver enzyme monitoring will be important
  • Blood glucose: Glucagon naturally raises blood sugar, but this appears to be offset by the GLP-1 and GIP components. In trials, glucose control improved overall

The overall tolerability in Phase 2 was acceptable, with discontinuation rates similar to other GLP-1 drugs. Phase 3 data with larger patient populations will provide a clearer safety picture.

Retatrutide vs Bariatric Surgery

The comparison is now genuinely relevant. Roux-en-Y gastric bypass typically produces 25–35% body weight loss at 1–2 years. Retatrutide's Phase 2 results (28.7%) fall squarely in that range.

FactorRetatrutide (projected)Bariatric Surgery
Weight loss~25–29%~25–35%
InvasivenessWeekly injectionMajor surgery
ReversibilityFully reversible (stop medication)Largely irreversible
Recovery timeNone2–6 weeks
Ongoing costHigh (monthly medication)One-time surgical cost + follow-up
Weight maintenanceRequires ongoing useMore durable but regain possible
Nutritional deficiency riskLowSignificant (requires lifelong supplementation)

For many patients, a non-surgical option that rivals surgery's results will be transformative. This doesn't make bariatric surgery obsolete — it remains the gold standard for severe obesity — but retatrutide could offer a compelling alternative for millions who wouldn't otherwise consider surgery.

The Pipeline Beyond Retatrutide

The obesity pharmacotherapy space is evolving rapidly. Beyond retatrutide, several other next-generation drugs are in development:

  • Orforglipron (Eli Lilly) — an oral GLP-1 agonist with the convenience of a daily pill and weight loss results approaching injectable GLP-1s. Could dramatically improve access in markets like Malaysia
  • Survodutide (Boehringer Ingelheim/Zealand) — a dual GLP-1/glucagon agonist showing ~19% weight loss in Phase 2
  • Amycretin (Novo Nordisk) — a novel dual amylin/GLP-1 agonist with early data showing up to 13% weight loss in just 12 weeks
  • CagriSema (Novo Nordisk) — combination of cagrilintide (amylin analogue) and semaglutide, showing up to 22.7% weight loss

We are entering a golden age of obesity medicine. By 2030, patients in Malaysia will likely have access to multiple highly effective options across different mechanisms, price points, and administration routes.

What This Means for Malaysian Patients

Why You Should Pay Attention Now

  • Malaysia has one of the highest obesity rates in Southeast Asia — approximately 50% of adults are overweight or obese. The need for effective pharmacotherapy is enormous
  • Retatrutide could shift the treatment paradigm — making medication-based weight loss a genuine alternative to surgery for severely obese patients
  • NPRA has shown willingness to approve these medications — Mounjaro's relatively swift approval (within a year of FDA approval) is encouraging

What to Do in the Meantime

If you're struggling with obesity and can't wait for retatrutide:

  1. Current options are already excellent: Ozempic (15% weight loss) and Mounjaro (22.5% weight loss) are available now in Malaysia
  2. Start building healthy habits today — regardless of which medication you eventually use, nutrition and exercise remain foundational
  3. Work with a qualified physician to develop a comprehensive metabolic health plan
  4. Stay informed — follow our updates as Phase 3 data emerges and regulatory timelines become clearer

Frequently Asked Questions

Can I get retatrutide in Malaysia now?

No. Retatrutide is an investigational drug still in Phase 3 clinical trials. It is not approved or legally available anywhere in the world. Be extremely cautious of any online sellers claiming to offer retatrutide — these products are likely counterfeit and potentially dangerous.

Will retatrutide replace Ozempic and Mounjaro?

Unlikely to "replace" them entirely. Different patients have different needs, tolerabilities, and budgets. Retatrutide will likely be positioned as a premium, maximum-efficacy option. Ozempic and Mounjaro will remain important treatments, potentially at lower price points as generics eventually emerge.

Are there clinical trials for retatrutide in Malaysia?

Eli Lilly's TRIUMPH programme includes global trial sites. Whether specific sites are open in Malaysia varies — check ClinicalTrials.gov or consult your endocrinologist about participation eligibility.

Is the 28.7% weight loss result reliable?

Phase 2 results are promising but must be confirmed in larger Phase 3 trials. It's common for Phase 3 results to be slightly more modest than Phase 2 (larger, more diverse patient populations). Even if the final number is 22–25%, retatrutide would still represent a meaningful improvement over current options.

The Bottom Line

Retatrutide is the most exciting drug in the obesity pipeline. Its triple mechanism of action produces weight loss results that rival bariatric surgery, and if Phase 3 trials confirm the Phase 2 data, it will fundamentally change how we treat obesity worldwide.

For Malaysian patients, the realistic timeline is 2028–2029 for availability. In the meantime, Ozempic and Mounjaro offer highly effective options that are available today. We'll continue updating this page as new data emerges from the TRIUMPH trial programme.