# Semaglutide vs liraglutide: what the direct comparison found, and what changed after it

> Source: https://peptidewellnessusa.com/peptides/compare/semaglutide-vs-liraglutide/
> Compare · GLP-1
> By PeptideWellness Editorial Team · Medically reviewed by Ksenia Petrushkina, PA-C, MPAS · Updated September 14, 2026 · 11 min read

Only one trial has ever compared these two drugs head to head for weight loss, and semaglutide won it by a factor of two and a half over 68 weeks. Then the patents moved: liraglutide now has eight approved generics and semaglutide has none.

These are the same class of drug, a decade apart. Liraglutide reached the US market in 2010 and defined what a GLP-1 receptor agonist could do; semaglutide arrived in 2017 and did more of it, less often. On the clinical question the answer has been settled since 2022 and it is not close.

What is no longer settled is the practical one. In December 2024 the first generic liraglutide was approved, and by August 2025 the generics had reached the obesity product too. Semaglutide has none. So the drug that loses the efficacy comparison by a factor of two and a half is the only one of the pair a generic manufacturer can sell — and that reopens a question the trial data had closed.

## Same target, two generations

Both molecules are analogues of GLP-1, the gut hormone released after eating that prompts insulin secretion, slows gastric emptying and signals satiety in the hypothalamus. Native GLP-1 is destroyed in about two minutes, so both drugs are built to survive: liraglutide carries a C-16 fatty acid chain that binds it to albumin and stretches its half-life to roughly 13 hours, semaglutide a longer C-18 chain plus amino-acid substitutions that make it last about a week.

That is the whole difference in kind, and it produces the difference in dosing: liraglutide is injected daily, semaglutide weekly. Everything else in this comparison follows from potency and from that schedule. For the wider framework, [what a peptide is](https://peptidewellnessusa.com/learn/what-is-a-peptide/) and [compounded versus branded](https://peptidewellnessusa.com/learn/compounded-vs-branded/) cover the ground underneath.

## The only obesity head-to-head: STEP 8

Until 2022 nobody had run the two against each other in people with obesity. STEP 8 [1] did it: a 68-week open-label phase 3b trial at 19 US sites, 338 adults with a BMI of 30 or more (or 27 with a weight-related comorbidity) and no diabetes, randomised to weekly semaglutide 2.4 mg, daily liraglutide 3.0 mg, or matching placebo.

Mean weight change at week 68 was **−15.8% with semaglutide against −6.4% with liraglutide** — a difference of 9.4 percentage points (95% CI −12.0 to −6.8, P below .001). Pooled placebo was −1.9%.

The response rates separate further than the averages:

| Lost at least | Semaglutide 2.4 mg | Liraglutide 3.0 mg | Odds ratio |
| --- | --- | --- | --- |
| 10% of body weight | 70.9% | 25.6% | 6.3 (3.5–11.2) |
| 15% of body weight | 55.6% | 12.0% | 7.9 (4.1–15.4) |
| 20% of body weight | 38.5% | 6.0% | 8.2 (3.5–19.1) |

All three at P below .001. Put plainly: better than one in three people on semaglutide lost a fifth of their body weight; one in sixteen did on liraglutide.

## The diabetes head-to-head: SUSTAIN 10

SUSTAIN 10 [2] is the diabetes counterpart: 577 adults, 30 weeks, weekly semaglutide 1.0 mg against daily liraglutide 1.2 mg — deliberately the doses most actually prescribed in Europe rather than the maximums.

HbA1c fell 1.7% with semaglutide and 1.0% with liraglutide, a treatment difference of 0.69 percentage points. Weight fell 5.8 kg against 1.9 kg, a difference of 3.83 kg. Both P below 0.0001, both favouring semaglutide, and the gap in the same direction as STEP 8 at doses less than half as high.

## What each drug does against placebo

The head-to-heads are small. The placebo-controlled programmes behind them are not, and they are worth reading as the reason each drug exists.

STEP 1 [3] enrolled 1,961 adults without diabetes for 68 weeks: −14.9% with semaglutide 2.4 mg against −2.4% with placebo. Half the semaglutide group lost 15% or more of their body weight; 5% of the placebo group did.

SCALE Obesity and Prediabetes [4] enrolled 3,731 adults for 56 weeks: −8.4 kg with liraglutide 3.0 mg against −2.8 kg with placebo, a difference of 5.6 kg. 63.2% lost at least 5% of body weight against 27.1% on placebo; 33.1% lost more than 10% against 10.6%.

Different trials, different lengths, different endpoints — you cannot subtract one from the other. But the shape matches what STEP 8 found when it ran them side by side.

## Tolerability does not follow efficacy

The obvious assumption is that the stronger drug is the harder one to take. The two head-to-heads disagree with each other about that, and the disagreement is instructive.

In STEP 8, gastrointestinal adverse events were reported by 84.1% on semaglutide and 82.7% on liraglutide — effectively identical. But discontinuation for any reason was **13.5% on semaglutide against 27.6% on liraglutide**: twice as many people stopped the weaker drug.

In SUSTAIN 10 it runs the other way. GI disorders were more frequent with semaglutide (43.9% against 38.3%), and adverse events leading to premature discontinuation were 11.4% against 6.6% — semaglutide worse on both.

The likeliest explanation is in the trial designs rather than the molecules. STEP 8 escalated semaglutide over 16 weeks and liraglutide over 4. A four-week climb to 3.0 mg is a fast titration, and fast titration is what produces the nausea people quit over. SUSTAIN 10 used doses less than half as high for both drugs, and there semaglutide's own escalation was the more demanding one.

What that means for a patient is narrower than "one is better tolerated": how quickly the dose is raised is at least as decisive as which drug it is, and it is the part a prescriber controls.

## Cardiovascular outcomes, two populations

Both drugs have a completed cardiovascular outcomes trial, and the temptation is to compare the hazard ratios. They are not comparable — the populations are different.

LEADER [5] randomised 9,340 patients with **type 2 diabetes** and high cardiovascular risk, median follow-up 3.8 years. The composite of cardiovascular death, non-fatal myocardial infarction or non-fatal stroke occurred in 13.0% on liraglutide against 14.9% on placebo (HR 0.87, 95% CI 0.78–0.97, P=0.01 for superiority). Cardiovascular death was 4.7% against 6.0% (HR 0.78) and all-cause death 8.2% against 9.6% (HR 0.85).

SELECT [6] randomised 17,604 patients with established cardiovascular disease, a BMI of 27 or more and **no diabetes**, mean follow-up 39.8 months. The same composite occurred in 6.5% on semaglutide 2.4 mg against 8.0% on placebo (HR 0.80, 95% CI 0.72–0.90, P below 0.001).

So liraglutide's cardiovascular evidence is in diabetes and semaglutide's is in obesity without it. For a patient with type 2 diabetes both drugs have outcome data; for a patient with obesity and cardiovascular disease but no diabetes, only semaglutide does.

## Daily against weekly

Fifty-two injections a year against three hundred and sixty-five. This is the difference patients actually feel, and it compounds: a weekly injection becomes a fixed appointment with yourself, a daily one becomes something to remember every morning and to pack for every trip.

It is also not free on the other side. A daily drug clears faster, so stopping it — because of side effects, surgery, pregnancy, or a supply gap — takes days rather than weeks. That matters more often than the tidier schedule suggests.

## What changed: liraglutide has generics

This is the part of the comparison that has moved since the trials were published, and it does not rest on anyone's press release: the FDA keeps a public register of every drug application it has approved, called Drugs@FDA, and it can be searched by molecule.

Read on 14 September 2026, that register lists **eight approved abbreviated new drug applications for liraglutide injection** [7] — the filing route for a generic — from Teva, Hikma, Biocon (two), Lupin, Orbicular (two) and Nanjing King Friend. All are 18 mg/3 mL, the same 6 mg/mL concentration as the brands.

For semaglutide it lists **none**. Apotex has a tentative approval, which confirms an application met FDA's standards but does not permit marketing while patents and exclusivity stand.

One detail matters more than the count, because the two brands are the same molecule at the same concentration in different pens. Victoza is the diabetes product; Saxenda is the obesity product, and it is the one this comparison is about. The generics split between them by therapeutic-equivalence code: five sit in Victoza's group, and **three sit in Saxenda's** — Teva, Biocon and Orbicular. Teva's, ANDA 214568, was approved on 27 August 2025.

The FDA announced the first liraglutide generic, Hikma's, referencing Victoza, on 23 December 2024 [8]. The obesity-side approvals followed through 2025.

## What that does to the choice

A generic does not make a drug cheap on the day it is approved — it makes it possible for it to become cheap, once more than one manufacturer is actually shipping. What it does immediately is change the shape of the decision.

Before generics, the comparison was: pay for the better drug or pay almost as much for the weaker one. There was no argument for liraglutide on cost, and its case rested on tolerability or on prescriber familiarity.

After them, liraglutide has the only route to a genuinely low price that exists in this class, and semaglutide has no such route until its patents lapse — and the tentative approvals now on file are what will move when they do.

That is not an argument for liraglutide. A drug that produces 6.4% weight loss where the alternative produces 15.8% is not made equivalent by being cheaper; for many people the cheaper drug simply will not reach the outcome they are treating for. It is an argument for asking the question in the right order: what the treatment needs to achieve first, what it costs second.

One caution on the supply side. Novo Nordisk's own NovoCare page for Saxenda [11] states that demand has affected availability and that patients may have difficulty filling prescriptions for the foreseeable future. A cheaper drug you cannot obtain is not cheaper.

## Compounding: the door is closing on both

Neither molecule is a live compounding opportunity any more, and the trajectory is the same for both.

Semaglutide was added to FDA's shortage list in 2022, which is what made mass compounding lawful, and the agency declared that shortage resolved [10] on 21 February 2025. On **30 April 2026 the FDA proposed excluding semaglutide, tirzepatide and liraglutide from the 503B Bulks List** altogether, finding no clinical need [9] for outsourcing facilities to compound them in bulk.

What survives is patient-specific compounding under 503A, where a clinician documents that the approved product will not serve a particular patient. That is a narrow gate, and it is narrower than most marketing implies.

## Who liraglutide is still the right answer for

The honest list is short, and none of the entries is "it works about as well".

**Patients who need a drug that clears quickly.** A 13-hour half-life against a week's is an advantage when treatment may have to stop abruptly.

**Adolescents.** Saxenda is approved from age 12 with a weight requirement above 60 kg; the paediatric route for liraglutide is older and better trodden.

**Patients with type 2 diabetes and cardiovascular disease** for whom LEADER's diabetes-population outcome data is the closer match to their situation.

**Patients who could not tolerate semaglutide** — and here the titration point from section 5 applies first. A slower climb on the same drug is worth trying before a switch.

**Patients for whom a generic is the difference between treatment and none.** This is the new entry, and it is real. It is also the one where the efficacy gap has to be stated plainly rather than papered over.

For everyone else starting GLP-1 therapy for weight, STEP 8 is the answer, and it is emphatic.

## Frequently asked

### Is semaglutide simply better than liraglutide?

For weight loss, yes, and by a wide margin: −15.8% against −6.4% over 68 weeks in the one trial that compared them directly. For glycaemic control it is also better, by about 0.7 percentage points of HbA1c. The reasons to choose liraglutide are about half-life, age, cost and tolerability history, not about efficacy.

### Is one easier to tolerate?

Neither consistently. Gastrointestinal side effects were near-identical in STEP 8 (84.1% against 82.7%), but twice as many people quit liraglutide; in SUSTAIN 10 semaglutide caused more discontinuations. The trial designs differed in how fast the dose was raised, and that appears to matter more than the molecule.

### Can I get generic semaglutide?

No. There is no approved generic semaglutide in the United States as of September 2026. Tentative approvals exist, which means an application has met FDA's scientific standards but cannot be marketed while patents and exclusivity remain.

### Is generic liraglutide the same as Saxenda?

Three of the eight approved generics sit in Saxenda's therapeutic-equivalence group and are rated as substitutable for it; the other five reference Victoza, the diabetes product. They are the same molecule at the same concentration, but the pens and the approved indications differ, so which generic you are offered matters.

### Does either have cardiovascular benefit?

Both have a positive outcomes trial, in different populations. Liraglutide's is in type 2 diabetes (LEADER, HR 0.87); semaglutide's is in obesity without diabetes (SELECT, HR 0.80). They should not be read as a ranking.

### What about compounded versions?

FDA proposed on 30 April 2026 to exclude both molecules, and tirzepatide, from the 503B bulks list. Bulk compounding of either is closing; patient-specific 503A compounding remains, on a narrow basis.

## References

1. [Rubino DM, Greenway FL, Khalid U, et al. Effect of weekly subcutaneous semaglutide vs daily liraglutide on body weight in adults with overweight or obesity without diabetes: the STEP 8 randomized clinical trial. *JAMA.* 2022;327(2):138-150. PMID 35015037.](https://pubmed.ncbi.nlm.nih.gov/35015037/)
2. [Capehorn MS, Catarig AM, Furberg JK, et al. Efficacy and safety of once-weekly semaglutide 1.0 mg vs once-daily liraglutide 1.2 mg as add-on to 1-3 oral antidiabetic drugs in subjects with type 2 diabetes (SUSTAIN 10). *Diabetes Metab.* 2020;46(2):100-109. PMID 31539622.](https://pubmed.ncbi.nlm.nih.gov/31539622/)
3. [Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity. *N Engl J Med.* 2021;384:989-1002. PMID 33567185.](https://pubmed.ncbi.nlm.nih.gov/33567185/)
4. [Pi-Sunyer X, Astrup A, Fujioka K, et al. A randomized, controlled trial of 3.0 mg of liraglutide in weight management. *N Engl J Med.* 2015;373:11-22. PMID 26132939.](https://pubmed.ncbi.nlm.nih.gov/26132939/)
5. [Marso SP, Daniels GH, Brown-Frandsen K, et al. Liraglutide and cardiovascular outcomes in type 2 diabetes. *N Engl J Med.* 2016;375:311-322. PMID 27295427.](https://pubmed.ncbi.nlm.nih.gov/27295427/)
6. [Lincoff AM, Brown-Frandsen K, Colhoun HM, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes. *N Engl J Med.* 2023;389:2221-2232. PMID 37952131.](https://pubmed.ncbi.nlm.nih.gov/37952131/)
7. [FDA. Drugs@FDA — approved applications for liraglutide and semaglutide injection, queried 14 September 2026.](https://www.accessdata.fda.gov/scripts/cder/daf/)
8. [FDA. FDA approves first generic of once-daily GLP-1 injection to lower blood sugar in patients with type 2 diabetes. 23 December 2024.](https://www.fda.gov/news-events/press-announcements/fda-approves-first-generic-once-daily-glp-1-injection-lower-blood-sugar-patients-type-2-diabetes)
9. [FDA. FDA proposes to exclude semaglutide, tirzepatide, and liraglutide from the 503B bulks list. 30 April 2026.](https://www.fda.gov/news-events/press-announcements/fda-proposes-exclude-semaglutide-tirzepatide-and-liraglutide-503b-bulks-list)
10. [FDA. Resolution of shortages of semaglutide injection products — declaratory order, 21 February 2025.](https://www.fda.gov/media/185526/download)
11. [NovoCare. Saxenda (liraglutide) injection 3 mg — product and availability information, read 14 September 2026.](https://www.novocare.com/obesity/products/saxenda.html)

## Medical disclaimer

This page is informational and is not medical advice. It compares published trial results; it cannot tell you which drug is appropriate for you, and neither drug is suitable for everyone — both carry a boxed warning for thyroid C-cell tumours and are contraindicated in people with a personal or family history of medullary thyroid carcinoma or MEN 2. Dose, titration speed and the decision to start or stop belong to a licensed prescriber who knows your history. Prices, approvals and supply change; every figure above carries the date it was read.