Best Peptides for Muscle Growth and Fat Loss

Peptides get sold for "muscle growth and fat loss" from two very different directions. One group, the GLP-1 and related incretin medicines, has some of the largest randomised trials in medicine behind it, with real drug approvals. The other, GH-axis secretagogues and myostatin blockers, mostly has small old studies, animal data, or nothing in humans at all. This page keeps the two separate and ranks each compound by what its own trials showed.

Approved GLP-1 medicines: the strongest fat-loss evidence, with a caveat

These are prescription medicines with some of the largest obesity trials ever run. All of them produce a mix of fat and lean mass loss, not fat-only loss, and none of the trials below isolated muscle preservation as an outcome.

Semaglutide (Ozempic, Wegovy) has the deepest evidence base of any weight-management drug on this list. STEP-1 randomised 1,961 adults without diabetes to weekly 2.4 mg injections, and SELECT went further, following 17,604 adults with cardiovascular disease for a cardiovascular outcome, not just weight. It has been registered with FDA Philippines since 2022.

Tirzepatide (Mounjaro) combines GIP and GLP-1 receptor activity in one molecule. Its SURMOUNT-1 trial (2,539 adults) reported more weight loss at every dose than semaglutide reported in its own trial. Mounjaro is sold at retail pharmacies here; Zepbound, the US weight-management brand, has no confirmed Philippine registration.

Liraglutide (Victoza, Saxenda) is the oldest of the three, dosed daily rather than weekly. Its SCALE trial (3,731 adults) and the LEADER cardiovascular trial (9,340 adults with diabetes) are both large, but its own weight-loss figures were smaller than the newer weekly drugs. US generics of both brands reached the market in 2024 and 2025.

Orforglipron (Foundayo) is the first GLP-1 medicine that is not a peptide, a small molecule taken as a daily tablet. The FDA approved it for weight management in April 2026, based on the 3,127-person ATTAIN-1 trial, which reported less weight loss than the injectable drugs above. No Philippine registration has been confirmed.

Mazdutide activates GLP-1 and glucagon receptors and is approved only by China's NMPA, based on the 610-person GLORY-1 trial. It has no US, EU or Philippine approval.

In large trials but not yet approved

Retatrutide activates GIP, GLP-1 and glucagon receptors and has produced the largest weight-loss figures on this page: 28.3% mean weight loss at 80 weeks in the 2,339-person TRIUMPH-1 phase 3 trial, rising to 30.3% at 104 weeks. It is not approved anywhere; Eli Lilly has said it plans to file with the US FDA in the first quarter of 2027. These figures come only from the verified trial data this site maintains; treat any retatrutide number seen elsewhere with caution.

CagriSema, a fixed combination of the amylin analogue cagrilintide with semaglutide, reported 22.7% mean weight loss among those who stayed on treatment in the 3,417-person REDEFINE 1 trial. Novo Nordisk filed for US FDA approval in December 2025. In a later head-to-head trial against tirzepatide 15 mg, it did not beat it and missed its non-inferiority goal.

Survodutide, a glucagon and GLP-1 dual agonist from Boehringer Ingelheim and Zealand Pharma, reported up to 13.0% mean weight loss at 76 weeks in its 725-person SYNCHRONIZE-1 trial. It remains investigational.

GH-axis compounds: raise growth hormone, weaker outcome data

These compounds push the pituitary to release more of the body's own growth hormone, raising IGF-1. The theory is that more GH and IGF-1 support lean mass and fat metabolism. The human outcome data for actual muscle or fat change is far thinner than for the GLP-1 drugs above.

Tesamorelin (Egrifta) is the only GH-axis compound with FDA approval, to reduce visceral fat in HIV-associated lipodystrophy. Its pivotal 412-person trial measured a 15.2% fall in visceral fat by CT scan over 26 weeks, versus a 5.0% rise on placebo. The label states it is not indicated for general weight loss.

MK-677 (ibutamoren) is an oral ghrelin mimetic, not a peptide. In a two-year trial in adults 60 to 81, it raised lean mass but not strength or physical function, raised fasting glucose, and a separate hip-fracture trial was stopped early over a heart failure signal.

Sermorelin, CJC-1295 and ipamorelin are shorter-acting secretagogues sold for the same purpose. Sermorelin's own US brand, Geref, was discontinued in 2008. CJC-1295's only human trials used the long-acting DAC version, and a phase 2 trial of it was halted in 2006 after a participant died; the shorter "no DAC" version sold today has no published human trial of its own. Ipamorelin's only efficacy trial, for bowel recovery, found no benefit over placebo, and the FDA recommended against compounding it in 2024.

GHRP-2, GHRP-6, IGF-1 LR3 and AOD-9604 sit at the weakest end of this group. GHRP-2 is approved in Japan only as a diagnostic test, not a treatment. GHRP-6 has small acute GH-release studies from the 1990s and nothing on muscle or fat outcomes. IGF-1 LR3 has never been tested in a published human trial. AOD-9604, a GH fragment built for fat loss, reduced fat in obese mice, but its six human trials measured safety rather than weight loss, and no regulator has approved it for that use.

Myostatin blockers: strong biology, thin or worrying human data

Myostatin normally limits muscle growth. Blocking it produces dramatic muscle growth in animals, which is why these compounds attract attention, but the human safety record is short and, in one case, stopped a trial.

Follistatin-344 binds and neutralises myostatin. Its only human data comes from gene therapy, a viral vector injected into the muscles of six people with Becker muscular dystrophy, not from injecting the follistatin protein itself, which has no published human trial.

ACE-031 is a decoy receptor that soaks up myostatin and related signals before they reach muscle. A single dose raised lean mass 3.3% in 48 healthy postmenopausal women. A phase 2 trial in boys with Duchenne muscular dystrophy was halted in 2011 after several developed nosebleeds, gum bleeding and dilated skin blood vessels, and the developers ended the programme in 2013.

Reading this list honestly

The pattern is hard to miss. The compounds with the strongest evidence, the approved GLP-1 medicines, are approved for weight management, not muscle, and every trial that measured body composition found a mix of fat and lean tissue lost. The compounds people buy hoping to add muscle, the GH secretagogues and myostatin blockers, mostly have the thinnest human data on this page. Evidence strength and marketing enthusiasm run in close to opposite directions here.

Status in the Philippines

Ozempic, Wegovy, Mounjaro, Victoza and Saxenda are registered, prescription medicines sold at Philippine retail pharmacies; prescribing belongs with a licensed Philippine physician. Selling unregistered GLP-1 products is being actively prosecuted: the NBI arrested two people in Tondo in May 2026 for selling unregistered tirzepatide online, and the Philippine College of Physicians has warned against compounded and non-registered versions. Every other compound on this page, retatrutide, the trial-stage combinations, and all the GH-axis and myostatin compounds, is unregistered with FDA Philippines and sold only through research-chemical channels. See the cost reality guide for verified pharmacy pricing.