Zepbound vs Victoza: Comparing a Newer and Older GLP-1

Last reviewed: May 12, 2026 Last updated: May 12, 2026

Written by: Jay Hastings , CEO of PlexusDx

Jay Hastings is the CEO of PlexusDx, a precision health company focused on genetic testing, blood biomarker insights, and personalized wellness recommendations. He has more than 20 years of experience across healthcare innovation, genomics, laboratory operations, healthcare investing, and strategic finance. His work has included scaling healthcare startups, leading CLIA lab integrations, and helping expand consumer access to precision health tools.

Medically reviewed by: Jayden Lee, PharmD, EMBA

Jayden Lee, PharmD, EMBA, is the PlexusDx Medical Science Liaison with a PharmD and MBA specializing in pharmacogenomics and clinical product development, with a proven ability to bridge the gap between genomic research and practical patient outcomes. Dr. Lee has more than 10 years of professional experience in clinical pharmacy, academia, and research.

This guide lives in the PlexusDx Education Hub, our library on GLP-1 medicines, weight-management protocols, and the inherited factors that shape metabolic outcomes. Browse all Peptides & GLP-1 education

This is an independent editorial review. PlexusDx has no commercial ties to Eli Lilly, Novo Nordisk, or any manufacturer named on this page.

Comparing Zepbound with Victoza is really a comparison across a decade of drug design. Victoza (liraglutide) was one of the first GLP-1 receptor agonists to reach patients, approved back in 2010 and dosed once daily. Zepbound (tirzepatide) is a newer dual-incretin molecule cleared for weight management. This review sets them side by side on mechanism, evidence, safety, and cost, then turns to the genetics that outlast any single prescription.

A first-generation GLP-1 next to a newer dual agonist

Victoza, made by Novo Nordisk, entered the U.S. market in 2010 for type 2 diabetes; its active ingredient, liraglutide, is dosed once daily. Zepbound, from Eli Lilly, is a much more recent arrival, cleared for chronic weight management in 2023 and for obstructive sleep apnea in adults with obesity in 2024. The two bookend how far the category has moved in roughly fifteen years.

How liraglutide and tirzepatide engage the receptors

Liraglutide is GLP-1-selective, acting on a single incretin receptor. Tirzepatide is a GIP/GLP-1 dual agonist, engaging two. Semaglutide and dulaglutide also fall in the GLP-1-selective group, while retatrutide, a triple GLP-1/GIP/glucagon agonist, is still investigational and not FDA-approved as of April 2026. Whatever the receptor count, all of these compounds converge on the GLP-1 receptor to slow gastric emptying, temper glucose after meals, and strengthen satiety cues.

Approved uses and dosing cadence

One practical contrast is how often each is taken: Victoza is a daily injection, whereas tirzepatide products are weekly. On labels, the class sorts by indication: Victoza (liraglutide) for type 2 diabetes in 2010; Zepbound (tirzepatide) for weight management in 2023 and sleep apnea in 2024; Mounjaro (tirzepatide) for diabetes in 2022; Ozempic (semaglutide) for diabetes in 2017; Wegovy (semaglutide 2.4 mg) for weight management in 2021; Rybelsus (oral semaglutide) for diabetes in 2019; Trulicity (dulaglutide) for diabetes in 2014. Retatrutide remains investigational.

The trial records behind each

Liraglutide's evidence rests on the LEAD program in diabetes and the LEADER cardiovascular-outcomes trial. Tirzepatide's sits in SURMOUNT for weight management and SURPASS for diabetes, with SURMOUNT-OSA supporting the sleep-apnea clearance. There is no head-to-head Zepbound-versus-Victoza trial; the closest cross-links in the literature, SUSTAIN 7 and SURPASS-2, used semaglutide as the reference. Compare study by study, since populations, doses, and endpoints were never designed to match.

Safety signals they hold in common

Despite the generational gap, the two share a safety framework. Both carry the boxed warning for thyroid C-cell tumors observed in rodents and are contraindicated with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2. Gastrointestinal effects, including nausea, vomiting, diarrhea, and constipation, dominate the common side-effect list and usually ease after dose escalation. Pancreatitis, gallbladder disease, and dehydration-related kidney injury are rare but serious.

Access, insurance, and monthly spend

Published U.S. list prices for the FDA-approved brands in this space ran roughly $815–$1,620 per month as of April 2026 (manufacturer list pricing). The figure a patient actually faces depends on plan coverage, the indication on the script, savings-card eligibility, and whether a licensed compounding route is open. A daily product like Victoza and a weekly one like Zepbound can also feel different in refill cadence and adherence, separate from sticker price.

The genetics that outlast either prescription

No matter which molecule a provider chooses, the inherited groundwork is identical. Variants in FTO influence appetite and adiposity set-point; GLP1R is the gene for the receptor these drugs target; MC4R governs energy balance; and TCF7L2 connects to glucose handling and GLP-1 secretion. Pathway-level by nature, they say nothing about whether Zepbound or Victoza will work for you; they map the metabolic backdrop a clinician is prescribing into.

PlexusDx offers semaglutide and tirzepatide through its Weight Management Protocols and does not sell, distribute, or prescribe liraglutide. The Precision Peptide Genetic Test analyzes 14 pathways, 49 peptides, 150+ genetic insights, including FTO, GLP1R, MC4R, and TCF7L2 variants that describe your baseline GLP-1, appetite, and energy-balance biology. Reading that profile before starting a protocol is the test before you invest approach: less guesswork, a sharper discussion with your healthcare provider.

Related reading on PlexusDx: Buy Zepbound Online, Discount Zepbound, How to Buy Zepbound, Online Zepbound.

Disclaimer: This article is educational. PlexusDx offers semaglutide and tirzepatide through its Weight Management Protocols and does not sell, prescribe, or recommend liraglutide. The Precision Peptide Genetic Test analyzes how your genes influence peptide-related biological pathways; it does not predict response to any specific medication. Consult a qualified healthcare provider before beginning any peptide protocol.

Start with the biology. Take the Precision Peptide Genetic Test, or explore the Weight Management Protocols.

Frequently Asked Questions

Is Victoza dosed differently from Zepbound?

Yes. Victoza (liraglutide) is a once-daily injection, while Zepbound (tirzepatide) is administered weekly. Beyond frequency, they differ in molecule and label: Victoza is approved for type 2 diabetes, and Zepbound for chronic weight management and sleep apnea. Dosing cadence can affect adherence and daily routine.

Is Victoza approved for weight loss?

No. Victoza (liraglutide) carries a type 2 diabetes indication, not chronic weight management. In this pairing, Zepbound (tirzepatide) holds the weight-management clearance. Liraglutide is also available under a separate weight-management brand, which is a different product from Victoza, so confirm the specifics with a provider.

Does the genetic test predict which drug fits me?

No. The Precision Peptide Genetic Test is not pharmacogenomic and does not forecast response to Victoza, Zepbound, or any medication. It analyzes pathway-level variants in FTO, GLP1R, MC4R, and TCF7L2 that outline baseline appetite and energy-balance biology, offering context for a provider conversation rather than a recommendation.

Why compare a 2010 drug with a newer one?

Because patients weighing options often see both. Victoza from 2010 represents an earlier generation of GLP-1 therapy, while tirzepatide is a newer dual-incretin design. Their approvals, dosing schedules, and trial programs differ, so the comparison highlights how the category evolved rather than declaring a single winner.

Medical and Editorial Standards

Medical review process: This article was reviewed for medical accuracy, scientific clarity, evidence alignment, and appropriate discussion of genetics, medications, supplements, biomarkers, and health-related claims.

Sources and evidence: PlexusDx educational content is developed using peer-reviewed research, clinical literature, reputable medical references, and, where applicable, public health or regulatory guidance. References are included at the end of the article when scientific, medical, or health-related claims are discussed.

Commercial transparency: PlexusDx offers genetic testing, blood biomarker testing, personalized supplement recommendations, and related precision wellness services. Product mentions are intended to help readers understand available options and should not be interpreted as medical advice.

Important disclaimer: PlexusDx educational content is for informational purposes only and should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about medications, supplements, genetic testing, lab testing, or health-related care.