Beyond Weight Loss: Tirzepatide as a Metabolic Disease‐Modifying Strategy for Metabolic Dysfunction‐Associated Steatohepatitis: A Narrative Review

ABSTRACT

Background

Metabolic dysfunction‐associated steatotic liver disease (MASLD) has emerged as the most prevalent chronic liver disease worldwide and a major contributor to liver‐related morbidity and mortality. Its progressive subtype, metabolic dysfunction–associated steatohepatitis (MASH), is characterized by hepatocellular injury, inflammation, and fibrosis, which may ultimately progress to cirrhosis and hepatocellular carcinoma. Despite the rapidly increasing global burden of MASH, effective pharmacological therapies remain limited. Lifestyle modification remains the cornerstone of management; however, achieving and maintaining the degree of sustained weight loss required for meaningful histological improvement is challenging in routine clinical practice.

Objective

This perspective review evaluates the emerging therapeutic potential of tirzepatide in the management of MASH.

Methods

Relevant mechanistic studies, clinical trials, and recent literature published between 2015 and 2025 were reviewed to evaluate the emerging role of tirzepatide and incretin‐based therapies in metabolic liver disease.

Results

Tirzepatide is a first‐in‐class dual glucose‐dependent insulinotropic polypeptide and glucagon‐like peptide‐1 receptor agonist that produces substantial metabolic benefits, including improved glycemic control, enhanced insulin sensitivity, and significant weight reduction. These effects directly address key drivers of MASLD and MASH, including hepatic lipid accumulation, insulin resistance, and systemic inflammation. Emerging clinical evidence, particularly from the SYNERGY‐NASH trial, suggests that tirzepatide may promote resolution of steatohepatitis and improvement in fibrosis in patients with biopsy‐confirmed MASH.

Conclusion

Tirzepatide represents a promising metabolic disease‐modifying therapy for MASH. Nevertheless, larger and longer‐term clinical studies are needed to establish its durability of benefit, long‐term safety, and optimal role within evolving treatment strategies for metabolic liver disease.

1. Introduction‐The Unmet Need in MASH Therapy

Metabolic dysfunction‐associated steatotic liver disease (MASLD), previously known as non‐alcoholic fatty liver disease (NAFLD), represents one of the most rapidly expanding causes of chronic liver disease worldwide. The recently adopted MASLD nomenclature reflects an evolving understanding that metabolic dysfunction, including obesity, insulin resistance, dyslipidemia, and type 2 diabetes mellitus (T2DM), is central to disease pathogenesis rather than merely an associated condition [1]. Within this spectrum, metabolic dysfunction‐associated steatohepatitis (MASH), formerly termed non‐alcoholic steatohepatitis (NASH), represents the progressive inflammatory phenotype characterized by hepatic steatosis, hepatocyte injury, lobular inflammation, and varying degrees of fibrosis [2].

The global burden of MASLD is substantial and continues to rise in parallel with the global epidemic of metabolic syndrome. Current estimates suggest that MASLD affects approximately 30%–35% of adults worldwide, while the prevalence of MASH is estimated to be between 5% and 7% of the general population [3]. Recent international consensus statements have redefined NAFLD as MASLD to better reflect the central role of metabolic dysfunction in disease pathogenesis [4]. The updated nomenclature emphasizes the strong association between hepatic steatosis and cardiometabolic risk factors, including obesity, insulin resistance, dyslipidemia, and type 2 diabetes mellitus, highlighting MASLD as a multisystem metabolic disorder rather than a liver‐restricted condition [1]. Epidemiological projections further suggest that the global prevalence of MASLD will continue to rise substantially in the coming decades, largely driven by the increasing burden of metabolic syndrome and diabetes worldwide [5].

MASLD is increasingly recognized as a multisystem cardiometabolic disease rather than a disorder confined to the liver. Although progressive fibrosis, cirrhosis, and hepatocellular carcinoma remain major hepatic complications, cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with MASLD. Patients with MASLD have a substantially increased risk of developing coronary artery disease, myocardial infarction, heart failure, atrial fibrillation (AF), heart failure with preserved ejection fraction (HFpEF), stroke, and cardiovascular death. Emerging evidence further suggests that MASLD contributes independently to cardiovascular risk, even after adjustment for conventional risk factors such as obesity, hypertension, dyslipidaemia, and type 2 diabetes mellitus, underscoring its role as a systemic metabolic disorder rather than an isolated liver disease [6, 7, 8].

The close association between MASLD and CVD is driven by several overlapping pathophysiological mechanisms. Insulin resistance, the hallmark of MASLD, promotes hepatic steatosis while simultaneously inducing endothelial dysfunction, oxidative stress, chronic low‐grade inflammation, and accelerated atherosclerosis. Hepatic lipid accumulation leads to increased production of inflammatory cytokines, adipokines, and hepatokines that perpetuate systemic inflammation and adverse cardiovascular remodeling. Moreover, mitochondrial dysfunction, activation of fibrotic pathways, expansion of epicardial adipose tissue, and alterations in myocardial energy metabolism contribute to structural and functional cardiac abnormalities, predisposing patients to AF, HFpEF, and coronary syndromes. These shared mechanisms explain why cardiovascular complications frequently precede liver‐related events in patients with MASLD [6, 7, 8, 9].

Recognition of MASLD as a systemic cardiometabolic disease has important therapeutic implications. Consequently, increasing attention has shifted toward therapies capable of simultaneously improving hepatic pathology and reducing overall cardiometabolic risk. Glucagon‐like peptide‐1 receptor agonizts (GLP‐1RAs) have demonstrated substantial benefits beyond glycaemic control, including clinically meaningful weight reduction, improved insulin sensitivity, favorable effects on blood pressure and lipid metabolism, attenuation of systemic inflammation, and proven reductions in major adverse cardiovascular events among high‐risk patients with type 2 diabetes. These pleiotropic effects have positioned incretin‐based therapies as promising disease‐modifying agents for MASLD and MASH. Building upon these observations, dual GIP/GLP‐1 receptor agonizts such as tirzepatide may provide broader metabolic and hepatic benefits, making them attractive therapeutic candidates capable of targeting both liver disease and the cardiometabolic dysfunction that drives its progression [1, 6, 7, 10].

Importantly, fibrosis stage remains the strongest predictor of liver‐related outcomes, including cirrhosis, hepatocellular carcinoma, liver transplantation, and mortality [11]. Therefore, therapies capable of simultaneously improving metabolic dysfunction and halting fibrosis progression represent a critical unmet need in MASH management. MASH has emerged as one of the leading indications for liver transplantation in several regions, underscoring the urgent need for effective therapeutic strategies [2].

Despite its increasing clinical burden, therapeutic options for MASH remain limited. Lifestyle modification, particularly weight reduction through dietary intervention and increased physical activity, remains the cornerstone of management. Clinical studies have demonstrated that weight loss of ≥ 10% can result in histologic resolution of steatohepatitis and regression of fibrosis in a subset of patients [12]. However, achieving and maintaining such weight loss in real‐world settings remains challenging, with long‐term adherence often limited.

Pharmacologic therapies for MASH have historically targeted either metabolic abnormalities or hepatic inflammation and fibrosis. Agents such as pioglitazone and vitamin E have demonstrated modest histologic benefits in selected patient populations but are limited by safety concerns and variable efficacy [13]. More recently, the thyroid hormone receptor‐β agonist resmetirom received regulatory approval as the first pharmacologic therapy specifically targeting MASH‐related fibrosis, marking a significant milestone in the field. Nevertheless, many current therapies address downstream hepatic manifestations rather than the systemic metabolic dysfunction driving disease progression.

Increasingly, MASLD and MASH are conceptualized as multisystem metabolic disorders involving complex interactions among the liver, adipose tissue, gut, and endocrine signaling pathways. Insulin resistance promotes hepatic de novo lipogenesis and impairs lipid oxidation, leading to hepatic fat accumulation and lipotoxic injury. This metabolic milieu subsequently triggers oxidative stress, inflammatory signaling, and fibrogenesis, driving progression toward advanced liver disease [14].

Given the systemic nature of MASLD, therapies capable of simultaneously targeting hepatic disease and cardiovascular risk have become increasingly attractive. Incretin‐based therapies, particularly GLP‐1RAs, have emerged as promising disease‐modifying agents owing to their ability to improve obesity, insulin resistance, glycaemic control, and cardiovascular outcomes while also reducing hepatic steatosis and inflammation. Building on these metabolic and cardiovascular benefits, dual GIP/GLP‐1 receptor agonizts such as tirzepatide have generated considerable interest as potential disease‐modifying therapies that may provide additional metabolic and hepatic benefits by addressing both the underlying metabolic dysfunction and hepatic manifestations of MASH [15].

2. Methodology

This narrative review was conducted using a structured narrative literature search to identify key mechanistic studies, clinical trials, and recent advances related to tirzepatide and incretin‐based therapies in MASLD and MASH. Relevant literature published between 2015 and June, 2026 was identified through searches of major biomedical databases, including PubMed, Scopus, and Web of Science.

Search terms included combinations of: “tirzepatide,” “dual GIP/GLP‐1 receptor agonist,” “MASLD,” “MASH,” “NASH,” “incretin therapy,” “GLP‐1 receptor agonizts,” “hepatic steatosis,” “insulin resistance,” and “liver fibrosis.” Priority was given to peer‐reviewed randomized controlled trials, mechanistic studies, meta‐analyses, and international consensus statements addressing metabolic liver disease and incretin‐based pharmacotherapies.

Additional references were identified through manual screening of reference lists from relevant articles and landmark clinical trials, including the SURPASS and SYNERGY‐NASH programs. Studies were selected based on their relevance to the pathophysiology of MASLD/MASH, mechanisms of dual incretin agonism, and emerging clinical evidence supporting tirzepatide as a potential disease‐modifying therapy.

As this manuscript is intended as a narrative review and not a formal systematic review, neither a quantitative meta‐analysis nor a formal risk‐of‐bias assessment was performed. Evidence was synthesized narratively focusing on study design, consistency of findings, clinical relevance and limitations of the current available literature.

3. Tirzepatide: A First in Class Dual GIP/GLP‐1 Receptor Agonist

3.1. Pharmacologic Profile and Mechanism of Action

Tirzepatide is a once‐weekly injectable peptide that acts as a dual agonist at both the glucose‐dependent insulinotropic polypeptide (GIP) receptor and the GLP‐1 receptor. This dual incretin mechanism distinguishes tirzepatide from traditional GLP‐1 receptor agonizts and represents a novel therapeutic strategy targeting multiple metabolic pathways simultaneously [10]. Activation of GLP‐1 receptors enhances glucose‐dependent insulin secretion, suppresses glucagon release, delays gastric emptying, and promotes central satiety. Meanwhile, GIP receptor activation contributes to improved adipocyte metabolism, enhanced insulin sensitivity, and modulation of lipid handling within adipose tissue. This dual receptor agonism has been proposed to produce complementary metabolic effects, as GLP‐1 primarily regulates appetite and insulin secretion, while GIP enhances adipocyte insulin sensitivity and lipid buffering capacity.

In adipose tissue, GIP signaling promotes insulin‐mediated glucose uptake and improved lipid buffering capacity, thereby reducing ectopic lipid deposition in non‐adipose organs such as the liver [10]. Emerging evidence suggests that dual incretin receptor agonism may influence hepatic lipid metabolism through several interconnected pathways, including activation of AMP‐activated protein kinase (AMPK), suppression of hepatic de novo lipogenesis, and enhancement of adipose tissue insulin signaling. Activation of AMPK promotes mitochondrial fatty acid oxidation while simultaneously suppressing lipogenic transcription factors such as sterol regulatory element‐binding protein‐1c (SREBP‐1c), thereby limiting triglyceride accumulation in hepatocytes [14]. In addition, incretin signaling may attenuate hepatic inflammation by modulating Kupffer cell activation and oxidative stress pathways, thereby limiting progression from simple steatosis to steatohepatitis [14].

Improved adipose tissue insulin sensitivity also reduces excessive lipolysis and decreases the release of circulating free fatty acids, which in turn limits hepatic lipid influx and mitigates lipotoxic injury. Furthermore, incretin signaling may influence the gut‐liver axis by modulating gastrointestinal hormone secretion, bile acid metabolism, and intestinal nutrient sensing, mechanisms that collectively contribute to improved hepatic metabolic homeostasis [13]. Through these integrated metabolic and inflammatory pathways, tirzepatide may reduce hepatic steatosis, attenuate inflammatory signaling, and potentially slow fibrogenesis in patients with MASH.

The synergistic activation of GLP‐1 and GIP receptors ultimately results in potent systemic metabolic effects, including substantial weight reduction, improved glycemic control, and favorable alterations in lipid metabolism [16]. These metabolic actions are highly relevant to the pathogenesis of MASH, as improved insulin sensitivity and reduced adipose tissue lipolysis decrease hepatic free‐fatty‐acid influx and hepatic de novo lipogenesis, two key processes driving hepatic steatosis and lipotoxic injury.

3.2. Differences From Traditional GLP‐1 Receptor Agonizts

Traditional GLP‐1 receptor agonizts such as liraglutide and semaglutide have demonstrated promising effects in patients with MASH. For example, semaglutide has been shown to increase rates of steatohepatitis resolution in randomized trials, although its effect on fibrosis improvement has been less consistent [17].

Tirzepatide differs from these agents through its dual receptor agonism, which may produce complementary metabolic effects. While GLP‐1 receptor activation primarily regulates appetite, insulin secretion, and gastric emptying, GIP receptor activation enhances adipocyte insulin sensitivity and lipid buffering capacity, thereby improving systemic metabolic homeostasis. The simultaneous activation of these pathways may result in greater reductions in body weight, insulin resistance, and hepatic lipid accumulation compared with GLP‐1 receptor agonism alone. Clinical trials evaluating tirzepatide in patients with obesity and T2DM have demonstrated greater weight loss and improvements in metabolic parameters compared with several established GLP‐1 receptor agonizts [18]. Clinical studies also suggest that tirzepatide may achieve greater weight reduction than currently available GLP‐1 receptor agonizts, which may be particularly relevant in MASH given the strong association between weight loss magnitude and histologic improvement in steatohepatitis. Furthermore, reductions in liver fat content assessed using magnetic resonance imaging‐proton density fat fraction (MRI‐PDFF) have been observed in patients treated with tirzepatide, supporting its potential role in improving hepatic steatosis [19].

These enhanced metabolic effects may translate into greater therapeutic benefits for MASH; however, whether these benefits reflect unique pharmacological actions or simply greater weight loss remains uncertain.

3.3. Systemic Metabolic Effects Relevant to Liver Disease

One of the most prominent clinical effects of tirzepatide is its profound impact on body weight. In large randomized clinical trials, patients receiving tirzepatide have achieved weight reductions exceeding 20% of baseline body weight in some cohorts [18]. Because sustained weight loss is strongly associated with improvements in hepatic steatosis and inflammation, this effect represents a key mechanism through which tirzepatide may benefit patients with MASH.

Insulin resistance plays a central role in the pathogenesis of MASLD and MASH. Tirzepatide improves insulin sensitivity through multiple mechanisms, including enhanced insulin secretion, reduced glucagon signaling, and improved peripheral glucose uptake. These metabolic effects reduce hepatic lipogenesis and promote more favorable lipid partitioning, thereby mitigating hepatic fat accumulation.

Beyond glycemic and weight effects, tirzepatide may influence hepatic disease through modulation of lipid metabolism and inflammatory signaling pathways. Dual incretin receptor activation has been associated with reductions in circulating triglycerides, improvements in adipose tissue function, and decreased systemic inflammation. These changes may reduce lipotoxic injury to hepatocytes and attenuate the inflammatory cascade that drives fibrogenesis in MASH.

Evidence supporting these mechanisms has emerged from clinical studies evaluating tirzepatide in patients with biopsy‐confirmed MASH. In the phase II SYNERGY‐NASH trial, treatment with tirzepatide for 52 weeks resulted in significantly higher rates of MASH resolution without worsening of fibrosis compared with placebo. Notably, up to 62% of participants receiving the highest dose achieved resolution of MASH compared with only 10% of those receiving placebo. Improvements were also observed in liver enzymes, liver fat content, and noninvasive markers of hepatic inflammation and fibrosis [2].

While longer and larger trials are required to determine whether these histologic improvements translate into reduced clinical outcomes such as cirrhosis or liver‐related mortality, these findings highlight the potential of tirzepatide to address the metabolic drivers underlying MASH progression.

Taken together, these metabolic and hepatic effects suggest that tirzepatide may represent a promising disease‐modifying strategy for MASH.

While these pathways provide a biologically plausible rationale for hepatic benefit, it remains uncertain whether the improvements observed in clinical studies are attributable to direct hepatic effects of dual GIP/GLP‐1 receptor agonism or are predominantly mediated through substantial weight loss and systemic metabolic improvement. This distinction remains an important area of ongoing investigation.

4. Mechanistic Rationale for Tirzepatide in MASH

4.1. Effects on Hepatic Steatosis

Tirzepatide, a dual agonist for GIP and glucagon‐like peptide‐1 (GLP‐1) receptors, is highly effective in reducing hepatic fat accumulation by activating numerous interrelated metabolic pathways. MASLD is a disease state characterized by hepatic steatosis due to increased free fatty acid uptake, increased lipogenesis, and decreased triglyceride export. An abnormality in basic processes such as fatty acid uptake, de novo lipogenesis, fatty acid oxidation, lipid export, and lipid droplet metabolism results in an accumulation of fat within the liver and steatosis [20].

Preclinical studies indicate that it decreases triglycerides and cholesterol in the liver. This results in an improvement in hepatic steatosis. This is because it decreases the levels of certain proteins that are involved in the uptake of fatty acids by cells. Such proteins include CD36 and odorant‐binding protein 2 A (OBP2A). This reduces the amount of lipids that enter hepatocytes. By restricting the intake of fatty acids, tirzepatide helps stop lipids from building up in the liver. This means that modifying how lipids are moved around is a key part of how it works to treat MASLD [21]. This finding is supported by recent studies showing that tirzepatide ameliorates hepatic steatosis through AMPK activation and subsequent inhibition of lipogenic and inflammatory (NF‐κB) signaling in cell and animal models of fatty liver disease [22].

In addition, Tirzepatide helps control blood sugar and makes insulin work better, which lowers the major reasons why fat builds up in the liver. Chronic hyperinsulinemia makes the liver create more fat, while insulin resistance in tissues outside the liver makes more free fatty acids that get to the liver. Tirzepatide reduces hepatic fat content and inhibits the accumulation of excess fat in hepatocytes by enhancing insulin sensitivity to glucose and increasing peripheral insulin responsiveness [23].

Tirzepatide also helps people lose a lot of weight and speeds up the metabolism of fat tissue. This includes speeding up the process of lipolysis in fatty tissues and reducing the flow of free fatty acids within the body. In addition to these enhancements, there are reductions in body weight and liver weight, as well as a general reduction in hepatic lipid accumulation. These results demonstrate that tirzepatide helps with hepatic steatosis by impacting the way the body absorbs lipids, the way the body creates new lipids, the way the body reacts to insulin, and the way the body regulates its own weight [24].

4.2. Anti‐Inflammatory Pathways of Tirzepatide in MASH

The anti‐inflammatory properties of Tirzepatide can be explained by the agonistic properties of incretin hormones GLP‐1 & GIP through the activation of the incretin system, resulting in decreased inflammation & increased levels of anti‐inflammatory cytokines such as insulin‐like growth factor (IGF) & adiponectin. Activation of the GLP‐1 receptor on immune cells inhibits major pro‐inflammatory pathways, including the NLRP3 inflammasome pathway & NF‐κB pathway, resulting in decreased levels of pro‐inflammatory cytokines including interleukin‐6 (IL‐6) & tumor necrosis factor‐alpha (TNF‐alpha) [25]. Emerging preclinical work also implicates lysophosphatidylinositol (LPI)/GPR55 signaling as a mechanistic node linking hepatic lipid handling to macrophage‐driven inflammation in MAFLD/MASH, providing a complementary pathway through which incretin‐based lipid lowering could attenuate hepatic inflammatory tone [26].

Tirzepatide's mechanism of action in reducing liver inflammation and metabolic dysfunction is probably effective in the treatment of MASH, given that it can target two main issues: inflammation and insulin resistance. Inflammation in adipose tissue is a major contributor to the progression of MASH as its is linked to metabolic dysfunction and liver inflammation. Studies reveal that tirzepatide can reduce the infiltration and polarization of M1 pro‐inflammatory macrophages in adipose tissue and can increase systemic insulin sensitivity [27].

While mechanistic studies on the impact of tirzepatide on the hepatic cytokine profile in humans are still limited, the clinical evidence provided by the use of GLP‐1 receptor agonizts suggests improved hepatic injury biomarkers such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as well as lobular inflammation. This suggests that the anti‐inflammatory effects of tirzepatide are closely correlated with the improvement in metabolic homeostasis. Additionally, the activation of the GLP‐1 receptor is associated with the inhibition of pro‐inflammatory pathways in the liver and peripheral tissues, which may be mediated by the reduction of oxidative stress levels and the improvement of insulin sensitivity to attenuate inflammation [21].

4.3. Potential Anti‐Fibrotic Effects of Tirzepatide

Tirzepatide may have indirect anti‐fibrotic effects in the context of MASH, mainly by addressing the underlying metabolic abnormalities. The pathogenesis of liver fibrosis in MASH is closely linked with insulin resistance, hepatic steatosis, and metabolic inflammation. Spontaneous resolution of MASH has been suggested to lead to the reversal of liver fibrosis, as well as a reduction in major adverse liver outcomes. In a natural history study, a reduction in disease activity was linked with the improvement of liver fibrosis, whereas an increase in disease activity was linked with the progression of liver fibrosis. Tirzepatide can lead to substantial weight loss, improve insulin resistance, and normalize hepatic lipid content, thereby reducing hepatocellular injury and the activity of hepatic stellate cells, which are the main effectors of liver fibrosis. The clinical evidence from the SYNERGY‐NASH phase II trial showed that treatment with tirzepatide increased the proportion of patients showing ≥ 1 stage improvement in liver fibrosis without worsening of MASH compared with placebo, which may indicate that the metabolic effects of tirzepatide have a role in slowing or reversing the progression of liver fibrosis [24].

Additional pre‐clinical studies have reinforced the therapeutic potential of tirzepatide in the management of fibrosis and steatohepatitis which is achieved by the reduction of hepatic steatosis, thus reducing lipotoxicity‐induced inflammatory signals. Notably, tirzepatide has been shown to suppress the expression of fatty acid uptake proteins such as CD36, which are implicated in the pathogenesis of hepatic steatosis [21]. The mechanistic pathways of tirzepatide in MASH in illustrated in Figure 1.

Figure 1.

Mechanistic pathways of tirzepatide in MASH [28, 29].

Despite these proposed mechanisms, the relative contribution of direct pharmacological effects versus weight‐loss‐mediated improvements remains unclear. Many of the metabolic pathways influenced by tirzepatide, including improved insulin sensitivity, reduced adipose tissue lipolysis, and decreased systemic inflammation, are themselves closely linked to weight reduction. As a result, current evidence does not definitively establish whether hepatic improvements occur independently of the substantial weight loss induced by treatment.

5. Clinical Evidence: What Do We Know So Far?

5.1. Evidence From the SURPASS Clinical Trial Program

The SURPASS Phase 3 clinical trial program investigated the safety and effectiveness of tirzepatide, administered once weekly, in individuals diagnosed with Type 2 Diabetes Mellitus, concentrating on glycaemic control and weight reduction. Within the clinical trials comprising the SURPASS program, notable enhancements were documented following tirzepatide administration concerning metabolic parameters. These included HbA1c levels, body weight, and insulin sensitivity, all of which are crucial factors in the development of hepatic steatosis [30].

In this study participants received either tirzepatide or Insulin Degludec for 52 weeks. Results found that, tirzepatide produced significantly greater reductions in liver fat content (LFC) compared with insulin degludec. The combined 10 mg and 15 mg tirzepatide doses resulted in an absolute LFC reduction of −8.09%, versus −3.38% with insulin degludec (p < 0.0001). Relative reductions in liver fat content ranged from approximately 30%–47%, as measured with the help of MRI‐PDFF. There were dose‐related improvements that were observed, where some studies showed that the relative reductions in liver fat content were as high as 50%–55%. There were reductions observed in visceral adipose tissue and abdominal subcutaneous adipose tissue, which showed that the metabolic benefits of the use of tirzepatide were quite wide‐ranging [19, 31].

5.2. Early Evidence From MASH‐Focused Clinical Trials

Aside from diabetes trials, new trials are underway to investigate tirzepatide's efficacy on MASH. In a phase 2 randomized study on patients with biopsy‐proven MASH and fibrosis stage F2–F3, tirzepatide showed considerable improvement on histological parameters after 52 weeks. Resolution of MASH with no worsening of fibrosis occurred with 44%, 56%, and 62% receiving 5 mg, 10 mg, and 15 mg tirzepatide, respectively, compared with 10% receiving placebo.

Furthermore, some preliminary results indicated that tirzepatide improved fibrosis‐related endpoints. In one study, approximately 53%–59% of tirzepatide‐treated patients achieved at least a one‐stage improvement in fibrosis without worsening MASH, as opposed to approximately 33% receiving placebo [24].

5.3. Comparison With Semaglutide and Other Incretin‐Based Therapies

Semaglutide and tirzepatide currently represent the two leading incretin‐based therapies under investigation for MASH. Although both agents have demonstrated favorable effects on hepatic steatosis, metabolic parameters, and histological outcomes, their comparative hepatic efficacy remains uncertain because no head‐to‐head randomized clinical trials have directly compared the two therapies in patients with biopsy‐confirmed MASH. Consequently, current comparisons are based largely on indirect evidence from separate clinical trials with differing study populations, study designs, treatment durations, and endpoints. Therefore, any conclusions regarding the superiority of one agent over the other should be interpreted with caution [32, 33].

Semaglutide has demonstrated robust efficacy in reducing hepatic steatosis and promoting the resolution of steatohepatitis in patients with MASH, although improvements in fibrosis have been less consistent across clinical trials. Importantly, semaglutide has demonstrated reductions in major adverse cardiovascular events (MACE) in patients with type 2 diabetes and obesity, making it an important benchmark against which newer incretin‐based therapies are evaluated [17].

Tirzepatide has demonstrated promising histological improvements in the SYNERGY‐NASH trial, together with substantial reductions in body weight and liver fat content that are consistent with findings from the SURPASS and SURMOUNT clinical trial programs. However, whether these hepatic benefits exceed those achieved with semaglutide remains uncertain because direct comparative trials have not yet been performed. Unlike semaglutide, which has established cardiovascular outcome evidence, dedicated cardiovascular outcome trial data for tirzepatide are still awaited. Ongoing cardiovascular outcome studies are expected to further clarify its cardiovascular efficacy and inform its clinical positioning [17].

While semaglutide acts exclusively through GLP‐1 receptor activation and tirzepatide combines GLP‐1 and GIP receptor agonism, newer agents such as survodutide incorporate glucagon receptor activation, reflecting the continued evolution toward multi‐target metabolic therapies. Survodutide, a dual GLP‐1/glucagon receptor agonist, has also emerged as a promising therapeutic candidate for MASH. Unlike tirzepatide, which combines GIP and GLP‐1 receptor agonism, survodutide incorporates glucagon receptor activation to enhance hepatic lipid oxidation while promoting clinically meaningful weight loss. Early clinical studies have demonstrated encouraging reductions in liver fat content and improvements in biomarkers of steatohepatitis and fibrosis, suggesting potential benefits for patients with MASH. However, long‐term histological outcomes, cardiovascular effects, and comparative efficacy relative to other incretin‐based therapies remain to be established. Ongoing phase III clinical trials are expected to further define its efficacy, safety, and position within the evolving therapeutic landscape of MASH [32, 33].

These findings highlight the rapidly evolving landscape of incretin‐based therapies for MASH. Although semaglutide, tirzepatide, and survodutide have each demonstrated promising hepatic and metabolic effects, direct comparative trials and long‐term outcome studies are required to determine their relative hepatic efficacy, cardiovascular benefit, and optimal positioning within future MASH treatment algorithms.

Table 1 summarizes the currently available evidence comparing incretin‐based therapies with respect to their hepatic and cardiovascular outcomes [41].

Table 1.

Comparison of incretin‐based therapies for MASH with respect to mechanism of action, hepatic efficacy, fibrosis, and cardiovascular evidence.

Drug	Mechanism of action	Weight loss	Hepatic efficacy	Fibrosis	Cardiovascular outcome evidence	Current status	Ref
Liraglutide	GLP‐1 receptor agonist	8%–10%	Improved hepatic steatosis and resolution of steatohepatitis (LEAN trial)	No consistent improvement	Established reduction in MACE in T2DM	Approved for T2DM/obesity	[15, 34]
Semaglutide	GLP‐1 receptor agonist	10%–15%	Significant improvement in hepatic steatosis and MASH resolution	Fibrosis improvement inconsistent	Established reduction in MACE in T2DM and obesity	Approved for T2DM/obesity	[17, 35, 36]
Tirzepatide	Dual GIP/GLP‐1 receptor agonist	15%–22%	Significant improvement in liver fat content and MASH resolution (SYNERGY‐NASH)	Significant improvement demonstrated in SYNERGY‐NASH	Dedicated cardiovascular outcome trial data awaited	Approved for T2DM/obesity; under investigation for MASH	[2, 18]
Survodutide	Dual GLP‐1/glucagon receptor agonist	15%–20%	Promising reductions in liver fat content and biomarkers of steatohepatitis	Under investigation	Cardiovascular outcome evidence not yet established	Phase III clinical trials	[37, 38]
Retatrutide	Triple GLP‐1/GIP/glucagon receptor agonist	Up to 24%	Marked reductions in liver fat in early‐phase studies	Under investigation	Cardiovascular outcome evidence under investigation	Phase III clinical trials	[39, 40]

5.4. Critical Appraisal of the Quality of Evidence

The excitement over the hepatic effects of tirzepatide should take into account several limitations inherent to the available evidence. SYNERGY‐NASH is a 2b‐phase, multi‐center, dose‐ranging, double‐blind, placebo‐controlled trial meant to explore the dose‐response relationship in three different doses, and not to provide final proof of the drug's efficacy [24, 42]. It included only adults aged 18–80 with confirmed MASH, BMI 27–50 kg/m², and F2–F3 stage of fibrosis in 130 sites in 10 countries [24]. Patients with F4 stage (compensated cirrhosis) or decompensated liver disease were not included. Those who agreed to undergo two liver biopsies and to endure an increasing dose of an injection for 52 weeks cannot be considered representative of the real‐life MASH patients. The outcome measure was evaluated at 52 weeks. That period is sufficient for evaluation of histologic change on paired biopsy but not enough for demonstrating sustainability of MASH resolution or fibrosis regression following cessation of the treatment, as well as long‐term events like cirrhosis, decompensation, or liver‐related mortality.

AEs were experienced by 92% of the patients receiving tirzepatide treatment compared to 83% receiving placebo and mostly involved the gastrointestinal tract, while the occurrence of AE‐related treatment discontinuation was comparable between the tirzepatide and placebo groups in SYNERGY‐NASH trial. But the meta‐analysis of pooled data from all tirzepatide clinical trials demonstrates that AE‐related treatment discontinuation increased with dose and was substantially more frequent than with placebo or GLP‐1 receptor agonizts used as comparators [42].

While more patients treated with tirzepatide experienced fibrosis improvement of ≥ 1 stage without deterioration of MASH [24], it is still unknown whether it is due to an actual antifibrotic effect of this drug or primarily the result of weight loss and steatosis reduction. Analysis of post hoc subgroup data from the SYNERGY‐NASH trial revealed that the hepatic effect was mostly due to weight loss. This raises the doubt whether the effect of any incretin‐based treatment with equivalent weight loss would be different. Collectively, these deficiencies show that while the current data set encourages tirzepatide as an interesting potential treatment, it does not justify it as a proven disease‐modifying agent. Data from phase 3 trials that have a longer duration of follow‐up and incorporate clinical endpoints are required. See Table‐2 for major Tirzepatide trials relevant to MASH.

Table 2.

Major tirzepatide trials relevant to MASH.

Trial name	Design of the study	Populaton	Duration	Primary endpoint	Key findings	Major limitations	Ref
SYNERGY‐NASH (NCT04166773	2b, multicenter, double‐blind, placebo‐controlled, dose‐finding	Biopsy‐confirmed MASH, F2–F3 fibrosis, BMI 27–50	52 weeks	MASH resolution without fibrosis worsening	Superior to placebo at all doses; ≥ 1‐stage fibrosis improvement also superior to placebo	Surrogate histologic endpoint; single time point biopsy interpretation; short follow‐up; F4/cirrhosis excluded; small N/arm	[24, 42]
SURPASS‐3 MRI substudy	3, RCT versus insulin degludec, open‐label	T2DM patients (not MASH‐selected)	52 weeks	LFC via MRI‐PDFF (exploratory)	More reduction in LFC in comparison with insulin degludec	No biopsy/histology data; imaging surrogate only. Not a MASH‐selected population. Open label design.	[19]
Phase 2 biomarker substudy (T2DM)	2, RCT	T2DM, non‐MASH‐selected	26 weeks	HbA1c, weight (exploratory biomarkers)	NASH biomarker changes (ALT, keratin‐18 fragments)	Post hoc/biomarker only; not powered for hepatic outcomes; no histology	[21]

6. Tirzepatide Versus Existing Emerging Mash Therapies

The pharmacological management of MASH remains challenging because of its complex and multifactorial pathogenesis involving metabolic dysregulation, chronic inflammation, lipotoxicity, and progressive fibrosis. The recent advances in the development of medications have been focused on targeting the key pathogenic pathways involved in MASH, including the regulation of hepatic lipid metabolism, modulation of inflammation and apoptosis, and inhibition and reversal of fibrosis. The thyroid hormone receptor beta agonist, Resmetirom, is the first drug that has been approved by the Food and Drug Administration for the treatment of MASH in the presence of fibrosis. This is an important milestone in the development of medications for MASH. Obeticholic acid, an agonist of the farnesoid receptor X, peroxisome proliferator‐activated receptor agonizts, GLP‐1RAs, and fibroblast growth factor 21 analogs are some of the other medications that are being investigated for the treatment of MASH. Each one of these medications affects one part of the pathophysiology of MASH [43].

Recently, the dual GIP and GLP‐1 receptor agonist Tirzepatide has been identified as an exciting candidate for MASH. Tirzepatide acts on multiple metabolic parameters that contribute to the pathogenesis of MASH by facilitating significant weight loss, improving insulin sensitivity, and reducing hepatic lipid content. A phase 2 clinical study conducted in 2024 showed that the administration of tirzepatide for 52 weeks increased the rate of MASH resolution without exacerbating fibrosis, making it an important drug in the management of MASH patients [24].

Despite these promising findings, larger and longer‐term clinical trials are needed to confirm the efficacy and safety of tirzepatide in the management of MASH, especially in terms of its effect on liver histology, inflammation, and fibrosis. A recent meta‐analysis of high‐quality RCTs comparing tirzepatide, lanifibranor and resmetirom confirmed that tirzepatide induced the largest decreases in serum aminotransferases and was also among the most effective agents for MASH resolution without fibrosis worsening [44], reinforcing the comparative positioning summarized in Table 3.

Table 3.

Conceptual comparison of tirzepatide versus emerging MASH therapies.

Drug class	Molecular target/Mechanism	Key metabolic effects	Effects on liver (Steatosis/Inflammation)	Effects on fibrosis	Key limitations	Reference
Tirzepatide (GIP/GLP‐1 dual agonist)	Dual activation of GIP and GLP‐1 receptors increases insulin secretion, decreases appetite, and increases insulin sensitivity.	Induces weight reduction (up to 15–20%) and improves glycemic control, thus addressing metabolic aspects of MASH	Significantly decreases hepatic fat content and inflammatory stress through metabolic improvement	SYNERGY‐NASH trial demonstrated > 50% resolution of MASH with significant improvement in fibrosis	Primarily GI adverse effects; long‐term results are still being investigated.	[24]
GLP‐1 receptor agonizts (e.g., semaglutide)	Activation of GLP‐1 receptors enhances insulin secretion, decreases appetite, and slows gastric emptying	Improves glucose metabolism and facilitates moderate weight loss	Decreases hepatic steatosis and inflammation mainly through weight loss	Increases MASH resolution, although fibrosis does not show significant improvement in clinical studies	GI side effects, although fibrosis benefits are modest	[17]
FXR agonizts (e.g., obeticholic acid)	Activation of farnesoid X receptor (FXR) plays a role in bile acid metabolism, which reduces hepatic lipogenesis and inflammation	effect on body weight or systemic metabolism.	Moderately reduces hepatic steatosis and inflammation	Significantly improves fibrosis, as seen in the REGENERATE study	Causes pruritus and increases LDL cholesterol.	[5]
THR‐β agonizts (e.g., resmetirom)	Selective activation of thyroid hormone receptor beta in the liver cells, enhancing fatty acid oxidation and lipid metabolism	Limited effect on weight but improves lipid profile, especially LDL	Significant reduction of hepatic fat, a relative reduction of up to 50% and absolute reduction of 11% at higher dose and drug exposure	Phase 3 trials showed improvement of steatohepatitis and fibrosis	Long‐term safety to be monitored	[45]
PPAR agonizts (e.g., pioglitazone, lanifibranor)	Activation of PPAR nuclear receptors for lipid metabolism, insulin sensitivity, and inflammatory pathways	Improves insulin sensitivity but causes weight gain	Improves steatosis and inflammatory activity to a moderate degree	Fibrosis improvement, especially for pan‐PPAR agonizts	Weight gain and edema	[46]

6.1. Weight‐Loss Dependent Versus Weight‐Loss Independent Effects

A major unresolved question is whether the hepatic benefits observed with tirzepatide show direct pharmacological effects on liver disease pathogenesis or are largely secondary to the substantial weight loss and metabolic improvements achieved during treatment. Weight reduction is a well‐established determinant of histological improvement in MASH, with previous studies demonstrating that weight loss exceeding 10% can result in steatohepatitis resolution and fibrosis regression irrespective of the intervention employed [12]. Given that tirzepatide can induce weight reductions approaching or exceeding 20% in some patient populations, it is plausible that a substantial proportion of its hepatic benefits are mediated through reductions in adiposity, improved insulin sensitivity, decreased free fatty acid flux to the liver, and amelioration of systemic inflammation [47].

Nevertheless, emerging mechanistic evidence suggests that dual GIP/GLP‐1 receptor agonism may exert effects extending beyond weight reduction alone through modulation of adipose tissue biology, hepatic lipid metabolism, inflammatory signaling pathways, and the gut‐liver axis [47]. However, definitive evidence demonstrating clinically meaningful weight‐loss independent hepatic benefits remains limited. Current clinical trials have not been specifically designed to separate direct hepatic actions from the metabolic consequences of weight loss, making causal interpretation challenging.

Similar debates have surrounded other incretin‐based therapies, including semaglutide, where substantial improvements in steatohepatitis have often paralleled marked reductions in body weight. Therefore, while tirzepatide appears highly promising as a therapy for MASH, it remains uncertain whether its advantages over other effective weight‐loss interventions arise from unique pharmacological mechanisms or simply from achieving greater and more sustained weight reduction. Future mechanistic and comparative studies are required to clarify this distinction and to determine the extent to which hepatic improvements are attributable to direct biological effects versus downstream consequences of metabolic improvement [48].

7. Safety, Tolerability, and Patient Selection

Tirzepatide has generally demonstrated a favorable safety and tolerability profile across clinical trials. However, gastrointestinal adverse events remain the most frequently reported treatment‐related side effects. Nausea, vomiting, diarrhea, constipation, and reduced appetite occur most commonly during the dose‐escalation phase and are usually mild to moderate in severity. In the SURMOUNT‐1 trial, adverse events leading to treatment discontinuation occurred in 4.3%, 7.1%, and 6.2% of participants receiving tirzepatide 5 mg, 10 mg, and 15 mg, respectively, compared with 2.6% in the placebo group [18]. Similarly, in the SYNERGY‐NASH trial, gastrointestinal events were the most common adverse events and were mostly mild or moderate in severity [2]. Gradual dose escalation, dietary counseling, and temporary dose adjustment may therefore be important strategies to improve tolerability and long‐term adherence.

Beyond gastrointestinal symptoms, several additional safety considerations warrant attention. Gallbladder‐related adverse events, including cholelithiasis and cholecystitis, have been reported with incretin‐based therapies and may be partly related to rapid weight loss and altered gallbladder motility. Although current evidence does not establish a definitive causal association between tirzepatide and pancreatitis, caution remains appropriate in patients with a previous history of pancreatitis. Delayed gastric emptying, a recognized effect of GLP‐1 receptor agonism, may also have implications for patients undergoing anesthesia, surgery, or endoscopic procedures because of potential aspiration risk [49].

Rapid and substantial weight loss induced by tirzepatide also raises nutritional considerations. Although weight reduction is central to improving MASH, excessive or rapid weight loss may contribute to loss of lean body mass, particularly among older adults, frail individuals, and patients with sarcopenia or poor nutritional reserve. Adequate protein intake, resistance exercise, and periodic nutritional assessment should therefore be encouraged during treatment.

Appropriate patient selection remains essential. Patients with obesity, type 2 diabetes mellitus, insulin resistance, and biopsy‐confirmed MASH are likely to derive the greatest benefit, as these metabolic abnormalities are directly targeted by dual GIP/GLP‐1 receptor agonism. In contrast, patients with lean MASLD, advanced frailty, sarcopenia, or limited nutritional reserve may require closer monitoring, as the benefits of weight loss may be less pronounced and the risk of nutritional compromise may be greater.

Patients with advanced fibrosis and compensated cirrhosis represent a distinct therapeutic challenge. Most clinical trials evaluating tirzepatide have excluded patients with cirrhosis, leaving limited evidence regarding efficacy and safety in this population. These patients may have portal hypertension, impaired hepatic reserve, altered drug handling, sarcopenia, and protein‐energy malnutrition, all of which may influence tolerability and outcomes. Until dedicated studies are available, tirzepatide should be considered cautiously in advanced liver disease and ideally within multidisciplinary care.

Real‐world implementation is another important consideration. The high cost of incretin‐based therapies, unequal global access, reimbursement limitations, potential drug shortages, and the need for long‐term weekly injections may restrict widespread use. Long‐term adherence may also be affected by gastrointestinal adverse effects, patient preference, and affordability. Therefore, future health‐economic studies are needed to determine the cost‐effectiveness and sustainability of tirzepatide in routine MASH care [50].

8. Future Directions and Research Gaps

Although tirzepatide has demonstrated promising therapeutic potential in the management of MASH, several important research gaps remain. One key priority is the incorporation of robust histology‐based endpoints into future clinical trials. Although imaging modalities and circulating biomarkers provide valuable non‐invasive information, liver biopsy remains the gold standard for evaluating steatohepatitis resolution and fibrosis regression. Recent evidence from the SYNERGY‐NASH trial suggests that tirzepatide may achieve MASH resolution without worsening fibrosis; however, larger multicentre studies with longer follow‐up and standardized histological assessment are required to confirm these findings across broader and more diverse patient populations [2].

Another important area of investigation is the long‐term effect of tirzepatide on fibrosis progression, cirrhosis, liver‐related complications, and overall survival. Given the multifactorial pathogenesis of MASH, monotherapy may be insufficient for many patients, particularly those with advanced fibrosis. Future therapeutic strategies are therefore likely to involve combination approaches targeting complementary pathogenic pathways. Tirzepatide primarily improves obesity, insulin resistance, and hepatic steatosis, whereas thyroid hormone receptor‐β agonizts such as resmetirom improve hepatic lipid metabolism, and emerging anti‐fibrotic therapies directly target fibrogenesis. Combining these agents may provide additive or synergistic benefits by simultaneously addressing metabolic dysfunction, hepatic inflammation, and progressive fibrosis [32, 45].

Future management of MASH is also expected to move towards precision medicine. Rather than applying a uniform treatment strategy, therapeutic decisions may increasingly be guided by genetic susceptibility, metabolic phenotype, disease stage, and biomarker‐guided risk stratification. Variants in genes such as PNPLA3 and TM6SF2 have been associated with disease progression and may help identify patients who are more likely to benefit from incretin‐based therapies. In addition, non‐invasive biomarkers and advanced imaging techniques, including MRI‐proton density fat fraction (MRI‐PDFF), transient elastography, and circulating molecular markers, may facilitate early treatment monitoring and improve patient selection while reducing dependence on liver biopsy [32].

Rather than replacing existing therapies, tirzepatide is likely to become an important component of future MASH treatment algorithms. Patients with predominant obesity, insulin resistance, and early‐stage MASH may benefit from tirzepatide as a first‐line metabolic disease‐modifying therapy, whereas patients with advanced fibrosis or persistent disease activity may ultimately require combination regimens incorporating anti‐fibrotic agents, thyroid hormone receptor‐β agonizts, fibroblast growth factor analogs, or other emerging multi‐target therapies. As dual‐ and triple‐incretin agonizts continue to evolve, treatment strategies are expected to become increasingly individualized according to disease stage, metabolic phenotype, genetic profile, and overall cardiometabolic risk [32, 33].

Despite encouraging short‐term results, most current studies have relatively limited follow‐up, making it uncertain whether improvements in liver fat and inflammation translate into durable reductions in cirrhosis, hepatic decompensation, hepatocellular carcinoma, and liver‐related mortality. Another important research priority is determining the extent to which hepatic improvements observed with tirzepatide are attributable to weight loss versus direct pharmacological effects. Future studies incorporating mediation analyses, mechanistic biomarkers, and direct comparative trials with other weight‐loss interventions will be essential to clarify whether tirzepatide confers hepatic benefits beyond those expected from weight reduction alone. Addressing these knowledge gaps will help define the optimal role of tirzepatide within future personalized treatment strategies for MASH [2, 10].

9. Conclusion

The rapidly increasing prevalence of MASH underscores the urgent need for therapeutic strategies that address the underlying metabolic drivers of disease progression. Historically, treatment approaches have focused either on lifestyle modification or pharmacologic agents targeting isolated aspects of hepatic pathology, such as inflammation or fibrosis. However, the complex and multifactorial pathogenesis of MASH necessitates therapies capable of simultaneously modulating systemic metabolic dysfunction, hepatic lipid accumulation, and inflammatory signaling pathways.

Current evidence suggests considerable potential for tirzepatide as a metabolic disease‐modifying therapy for MASH; however, this conclusion is based primarily on early‐phase clinical trials with relatively short follow‐up periods, and confirmation from adequately powered phase 3 studies with long‐term histological and clinical outcome data will be necessary before its role in routine MASH management can be fully established. As a dual GIP and GLP‐1 receptor agonist, tirzepatide exerts broad metabolic effects that directly target key mechanisms underlying MASLD and MASH. By improving insulin sensitivity, promoting substantial weight reduction, and reducing hepatic lipid accumulation, tirzepatide may interrupt the metabolic cascade that drives lipotoxicity, inflammation, and fibrogenesis, although the extent to which these benefits are mediated by direct drug effects versus profound weight reduction remains an area of active investigation. Early clinical evidence, particularly from the SYNERGY‐NASH trial, suggests that tirzepatide may achieve meaningful rates of steatohepatitis resolution and fibrosis improvement, highlighting its potential as a disease‐modifying therapy rather than merely a metabolic adjunct.

Nevertheless, several important questions remain. Long‐term studies are required to determine whether improvements in metabolic and histologic endpoints translate into reductions in clinically meaningful outcomes such as cirrhosis, hepatic decompensation, hepatocellular carcinoma, and liver‐related mortality. In addition, the optimal positioning of tirzepatide within the evolving therapeutic landscape of MASH, including its potential role in combination regimens with emerging anti‐fibrotic agents and its integration into precision medicine approaches, remains to be defined.

Taken together, these findings suggest that dual incretin–based therapies may represent a significant step toward a more integrated, metabolism‐focused approach to MASH management. As clinical evidence continues to evolve, tirzepatide and related agents may play a central role in reshaping the therapeutic paradigm for metabolic liver disease, offering new opportunities to modify the natural history of this increasingly prevalent global condition.

Author Contributions

Zubaier Ahmed: conceptualization, writing – original draft, writing – review and editing. Nashrah Mustafa: writing‐original draft, supervision, writing – review and editing. Tamanna Sarkar: data curation, writing – original draft. Hasina Yasmin: writing – review, and editing.

Funding

The authors have nothing to report.

Conflicts of Interest

The authors declare no conflicts of interest.

Transparency Statement

The lead author, Zubaier Ahmed, affirms that this manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.

Ahmed Z., Mustafa N., Sarkar T., and Yasmin H., “Beyond Weight Loss: Tirzepatide as a Metabolic Disease‐Modifying Strategy for Metabolic Dysfunction‐Associated Steatohepatitis: A Narrative Review,” Health Science Reports 9 (2026): e73044, 10.1002/hsr2.73044.

Data Availability Statement

Data sharing not applicable–no new data generated, or the article describes entirely theoretical research. All authors have read and approved the final version of the manuscript Zubaier Ahmed had full access to all of the data in this study and takes complete responsibility for the integrity of the data and the accuracy of the data analysis.