Moderate · human
This network meta-analysis (NMA) systematically synthesized evidence from 25 randomized controlled trials across 12 interventions to compare the weight-loss efficacy and safety of four advanced anti-obesity medications — tirzepatide, semaglutide, cagrilintide, and the combination CagriSema (cagrilintide + semaglutide) — in adults with overweight or obesity. Searches were conducted across PubMed, Scopus, and Cochrane Central. Using random-effects NMA models, the study found that tirzepatide 15 mg produced the greatest mean percent body weight reduction (−17.97%), closely followed by CagriSema (−17.84%) and semaglutide 7.2 mg (−14.66%). For achieving ≥20% body weight loss, CagriSema showed the highest relative risk (RR 27.82), followed by tirzepatide 15 mg (RR 23.70). All agents increased gastrointestinal adverse events (RR 1.33–1.91) relative to placebo, with the highest treatment discontinuation seen with semaglutide 7.2 mg (RR 3.09). Serious adverse events were comparable to placebo across all regimens. Key limitations include reliance on indirect comparisons due to absence of head-to-head trials, potential heterogeneity across trial populations and follow-up durations, and the emerging/limited trial data for CagriSema specifically. The authors conclude that both tirzepatide and CagriSema represent leading options for substantial weight loss but call for direct comparative trials.
Endocrinology, diabetes & metabolism · Jul 2026DOI ↗ Moderate · humanPreprint
This systematic review and meta-analysis, conducted following PRISMA 2020 guidelines, examined the effects of GLP-1 receptor agonists (semaglutide, liraglutide) and the dual GIP/GLP-1 receptor agonist tirzepatide on obstructive sleep apnea (OSA) severity, as measured by apnea-hypopnea index (AHI). The authors searched PubMed, Google Scholar, and SciSpace through May 2026 and included 40 studies involving adults with OSA receiving GLP-1–based therapies with quantitative AHI outcomes. The review found that tirzepatide was associated with greater AHI reductions (−25.3 to −29.3 events/h; approximately 50.7%–58.7%) compared with liraglutide (−12.2 events/h; ~25%), and a pooled meta-analytic estimate showed an overall AHI reduction of −16.57 events/h across therapies. The authors attributed these effects primarily to weight loss, while noting emerging evidence for potential weight-independent mechanisms. Limitations include the heterogeneity of included studies, reliance on a preprint-stage document, and the inability to fully disentangle weight-mediated versus direct effects. The authors conclude that GLP-1–based therapies, particularly tirzepatide, may represent meaningful treatment options for obesity-related OSA, especially among patients with poor CPAP adherence.
Unknown journal · Jun 2026DOI ↗ Moderate · human
This systematic review and network meta-analysis (NMA) evaluated the comparative efficacy of pharmacological interventions—at specific dosages—for improving liver fibrosis in adults with metabolism-associated steatotic liver disease (MASLD) and fibrosis stages F1–F3. Researchers searched three databases through July 2025, identifying 13 randomized controlled trials encompassing 3,871 patients and 12 distinct drug regimens. Using both direct comparisons and network meta-analysis, the study found that six interventions—resmetirom (two doses), survodutide, and tirzepatide (three doses)—were significantly more effective than placebo at achieving NASH resolution without worsening fibrosis. Surface Under the Cumulative Ranking (SUCRA) analysis ranked survodutide 6 mg/week highest, followed by tirzepatide 15 mg/week; emricasan 10 mg/day ranked lowest. The authors concluded that survodutide, efruxiferimin, resmetirom, and denifanstat showed the most promise for this population, while emricasan was not supported. Limitations include the moderate number of included trials, potential heterogeneity across study populations and outcome definitions, and the indirect nature of many NMA comparisons, which may limit the precision of the relative effect estimates.
Journal of translational medicine · May 2026DOI ↗ Moderate · human
This systematic review and meta-analysis synthesized evidence from three placebo-controlled randomized controlled trials (total n = 258) examining semaglutide in adults with schizophrenia spectrum disorders (SSDs). The authors conducted a preregistered search, pooled outcomes using random-effects meta-analysis, and assessed evidence certainty using GRADE criteria. The included trials tested semaglutide over 26–36 weeks. The study found that, compared to placebo, semaglutide was associated with statistically significant reductions in body weight (approximately −11.3 kg), BMI (approximately −3.6 kg/m²), HbA1c (approximately −0.37%), and fasting glucose. On the safety side, semaglutide was associated with meaningfully higher risks of abdominal pain, vomiting, and constipation, consistent with the known gastrointestinal profile of GLP-1 receptor agonists; no elevated risk of serious adverse events was observed. The authors note that the overall evidence base is limited by a small number of trials, modest combined sample size, and relatively short follow-up durations. No trials of tirzepatide in this population were identified. The authors conclude that semaglutide shows promise as an adjunctive metabolic treatment in SSDs but call for larger, longer trials.
BJPsych open · May 2026DOI ↗ Moderate · human
This observational study used two target-trial emulations to compare cardiovascular outcomes among commercially insured U.S. adults with type 2 diabetes (T2D) and atherosclerotic cardiovascular disease (ASCVD) who initiated tirzepatide, dulaglutide, or semaglutide between June 2022 and December 2024. Using propensity-score (PS) 1:1 matching to reduce confounding, the researchers formed two cohorts: 9,233 tirzepatide–dulaglutide pairs and 25,266 tirzepatide–semaglutide pairs. The primary outcome was a modified MACE composite (nonfatal myocardial infarction, nonfatal stroke, and all-cause death). The study found that tirzepatide initiators had a statistically significantly lower rate of modified MACE compared with dulaglutide initiators (HR 0.80; 95% CI 0.65–0.99), largely driven by reduced all-cause mortality (HR 0.60; 95% CI 0.43–0.83); tirzepatide was also associated with fewer pneumonia-related hospitalizations versus dulaglutide. No significant difference in modified MACE was observed between tirzepatide and semaglutide initiators (HR 1.03; 95% CI 0.90–1.17). Key limitations include the observational design, potential residual confounding, reliance on administrative claims data, and a relatively short follow-up window.
Diabetes care · May 2026DOI ↗ Moderate · human
This study aimed to indirectly compare the efficacy and safety of injectable tirzepatide (a dual GIP/GLP-1 receptor agonist) with oral semaglutide (a GLP-1 receptor agonist) for weight management in adults with overweight or obesity but without type 2 diabetes. Because no head-to-head trial exists, researchers used multilevel network meta-regression (ML-NMR) to adjust for baseline differences in sex, ethnicity, and outcome measures between two pivotal trials: SURMOUNT-1 (tirzepatide, 72 weeks) and OASIS 1 (oral semaglutide, 68 weeks). After adjustment, the analysis found that tirzepatide at two of the three doses studied was associated with statistically significantly greater reductions in body weight and waist circumference compared with oral semaglutide. Tirzepatide was also associated with higher odds of achieving clinically meaningful weight-loss thresholds (≥5%, ≥10%, ≥15%, and ≥20% body weight reduction). Cardiometabolic outcomes and safety profiles were reported as improved or broadly comparable for tirzepatide versus oral semaglutide. Key limitations include the indirect nature of the comparison, differences in trial duration and populations, and the inability to fully control for all confounders across separate trials. The findings should be interpreted cautiously pending direct head-to-head evidence.
Diabetes, obesity & metabolism · Apr 2026DOI ↗ Moderate · human
This large genome-wide association study (GWAS) investigated whether genetic variants explain why people respond differently to GLP-1 receptor agonists (GLP-1 RAs) such as semaglutide and tirzepatide. Researchers analyzed self-reported weight loss and side effects in 27,885 individuals on GLP-1 RA therapy. The study identified a missense variant in the GLP1R gene significantly associated with greater weight loss efficacy, with carriers of the effect allele losing an additional estimated 0.76 kg per copy. Separate genetic associations were found linking variants in both GLP1R and GIPR to nausea or vomiting during GLP-1 RA treatment; notably, the GIPR association appeared specific to tirzepatide users, consistent with tirzepatide's dual GLP-1/GIP receptor mechanism. The authors built a broader predictive model incorporating these findings, suggesting the potential to stratify patients by expected efficacy and side effect risk—a step toward precision medicine for obesity. Key limitations include reliance on self-reported outcomes, which may introduce recall and reporting bias, and the observational nature of the design, which limits causal inference beyond the genetic associations themselves.
Moderate · human
This systematic review and meta-analysis pooled data from three head-to-head randomized or controlled trials comparing tirzepatide (a dual GIP/GLP-1 receptor agonist) with semaglutide (a selective GLP-1 receptor agonist) in adults with obesity and/or type 2 diabetes. Studies were identified through searches of PubMed, Embase, and ScienceDirect up to February 2026. Using a random-effects model, the authors found that tirzepatide was associated with significantly greater weight reduction compared to semaglutide (pooled mean difference: −5.19 kg) and a higher likelihood of achieving ≥10% weight loss (pooled risk ratio: 1.50). No statistically significant differences were observed in overall adverse events or gastrointestinal events between the two agents; however, serious adverse events were reported more frequently with tirzepatide (risk ratio: 1.83). Key limitations include a very small number of included studies (n=3), substantial statistical heterogeneity in weight-related outcomes (I² >86%), and insufficient follow-up duration to draw conclusions about long-term cardiovascular safety. The authors note that further studies with longer follow-up are needed to confirm the cardiometabolic safety profile of tirzepatide relative to semaglutide.
Nepal journal of epidemiology · Apr 2026DOI ↗ Moderate · human
This systematic review and meta-analysis (PRISMA 2020, PROSPERO-registered) pooled three randomized controlled trials (N = 13,590 adults with type 2 diabetes) comparing once-weekly tirzepatide — a dual GIP/GLP-1 receptor agonist — against dulaglutide (a GLP-1 receptor agonist) over at least 26 weeks. The primary safety outcome was overall adverse event incidence, which the study found did not differ significantly between treatments (RR 1.04; moderate-certainty evidence). However, discontinuation due to adverse events was consistently higher with tirzepatide (RR 1.32; high-certainty evidence), suggesting a tolerability-persistence trade-off. Glycemic target achievement (HbA1c) was population-dependent: tirzepatide showed consistent benefit at the primary threshold in treatment-naïve patients receiving lower-dose dulaglutide, while the advantage narrowed in patients with established cardiovascular disease on higher-dose dulaglutide; heterogeneity was extreme at the strictest threshold. Weight-loss threshold achievement favored tirzepatide, though evidence certainty was very low due to substantial heterogeneity. Serious adverse events did not differ significantly. Key limitations include only three included trials, high heterogeneity for several outcomes, and restricted generalizability across patient subgroups. GRADE certainty ranged from very low to high across outcomes.
Healthcare (Basel, Switzerland) · Mar 2026DOI ↗ Moderate · human
This retrospective cohort study used the TriNetX global federated electronic health record (EHR) database to compare real-world cardiovascular outcomes between tirzepatide (a dual GIP/GLP-1 receptor agonist) and semaglutide (a GLP-1 receptor agonist) in non-diabetic adults treated for obesity. Patients who initiated either medication between November 2023 and August 2024 were included, with individuals having recent atherosclerotic events, prior heart failure, or treatment crossovers excluded. After 1:1 propensity score matching yielding 35,336 pairs, the study found that tirzepatide was associated with a statistically significantly lower incidence of the composite primary endpoint — all-cause death, acute coronary syndrome, stroke, or new-onset heart failure — at 12 months (1.90% vs. 2.18%; HR 0.86). This difference was primarily driven by a reduction in new-onset heart failure (both reduced and preserved ejection fraction). No significant differences were observed for all-cause mortality, acute coronary syndrome, or stroke individually. Tirzepatide also produced greater mean weight loss. Limitations include the retrospective observational design, reliance on EHR coding accuracy, inability to confirm medication adherence, short follow-up duration, and potential for residual confounding despite propensity matching.
Diabetes, obesity & metabolism · Mar 2026DOI ↗ Moderate · human
This retrospective cohort study used electronic health records from a large health system in Ohio and Florida (January 2021–June 2025) to examine real-world obesity treatment patterns and weight changes among adults who discontinued injectable semaglutide or tirzepatide within 3–12 months of initiation. A total of 7,938 patients (mean age ~56 years; ~64% female) were included. The study found that within one year of discontinuation, roughly 19.6% restarted the same medication and 35.2% received an alternative obesity treatment (most commonly another medication). Patients treated for obesity lost a mean of 8.4% of body weight before discontinuation, while those treated for type 2 diabetes lost 4.4%. In the year following discontinuation, the average weight change was modest (+0.5% for obesity indication; −1.3% for T2D indication), but with considerable individual-level variability—meaning some patients regained weight substantially while others did not. Key limitations include the retrospective, observational design (precluding causal inference), potential confounding by unmeasured factors, and restriction to a single health system in two U.S. states, which may limit generalizability.
Diabetes, obesity & metabolism · Mar 2026DOI ↗ Moderate · human
This large retrospective cohort study examined real-world trends in 1-year treatment persistence and adherence among commercially insured adults without diabetes who newly initiated high-potency, weight loss-indicated GLP-1 receptor agonists (GLP-1RAs) — specifically semaglutide (Wegovy) and tirzepatide (Zepbound) — between January 2021 and June 2024. Using integrated medical and pharmacy claims data from approximately 17.9 million members, researchers identified 33,607 eligible new initiators. The study found that 1-year persistence nearly doubled over the observation period, rising from 33.2% in 2021 to 60.9% in the first half of 2024. Tirzepatide demonstrated notably higher persistence (approximately 64%) compared to semaglutide during overlapping availability years. The authors suggest that resolution of GLP-1RA product shortages, improved side effect and dose escalation management, and lifestyle support programs may have contributed to improving persistence trends. Key limitations include reliance on claims data (which cannot capture clinical nuance or patient-reported reasons for discontinuation), a commercially insured-only population limiting generalizability, and the inability to distinguish voluntary discontinuation from access-related gaps. The authors call for further research into discontinuation reasons and long-term cost-effectiveness.
Journal of managed care & specialty pharmacy · Mar 2026DOI ↗ Moderate · human
This systematic review and frequentist network meta-analysis (NMA) examined the comparative cardiovascular efficacy of tirzepatide (a dual GIP/GLP-1 receptor agonist) versus GLP-1 receptor agonists (GLP-1RAs) and placebo in adults with type 2 diabetes (T2D) and established or high-risk atherosclerotic cardiovascular disease (ASCVD). Eleven randomized controlled trials were included — ten evaluating GLP-1RAs and one evaluating tirzepatide (SURPASS-CVOT). In the class-level analysis, the study found that tirzepatide was associated with statistically significant reductions in MACE, cardiovascular mortality, all-cause mortality, non-fatal myocardial infarction, and non-fatal stroke compared to placebo. In the agent-level analysis, tirzepatide reduced MACE compared to placebo and lixisenatide specifically, while appearing broadly comparable to other individual GLP-1RAs. Subgroup and leave-one-out sensitivity analyses were consistent with primary findings. A key limitation is that only one tirzepatide RCT (SURPASS-CVOT) was available, constraining direct head-to-head NMA comparisons between tirzepatide and individual GLP-1RAs and reducing the precision of tirzepatide-specific estimates. The authors concluded that tirzepatide may provide cardiovascular benefit at least comparable to established GLP-1RAs, though this inference is based on indirect comparisons.
Cardiovascular diabetology · Feb 2026DOI ↗ Moderate · human
This systematic review and meta-analysis examined the association between glucagon-like peptide-1 receptor agonists (GLP-1RAs) and heart rate (HR) changes in people with overweight or obesity who do not have diabetes. Researchers searched four major databases (PubMed, Web of Science, Embase, and Cochrane Library) and ultimately included 12 randomized controlled trials. Using both pairwise and network meta-analysis methods, the study calculated mean differences (MDs) in HR compared to placebo. Pairwise meta-analysis found that all analyzed GLP-1RAs — including liraglutide, semaglutide, orforglipron, oral semaglutide, tirzepatide, retatrutide, and the drug class overall — were associated with statistically significant increases in heart rate versus placebo. Network meta-analysis, which allows indirect comparisons across agents, suggested that orforglipron 36 mg was associated with the most pronounced HR increase, while tirzepatide 5 mg showed the least increase (and its result was not statistically significant). Key limitations include the indirect nature of network comparisons, variability in trial designs and follow-up durations, and the restriction to a non-diabetic population, which limits generalizability. The clinical significance of the observed HR increases was not fully addressed.
European journal of medical research · Jan 2026DOI ↗ Moderate · human
This systematic review, following PRISMA 2020 guidelines, examined the frequency, severity, and types of gastrointestinal (GI) adverse effects associated with anti-obesity medications in non-diabetic adults with obesity. Researchers searched PubMed, Google Scholar, BMJ, and Web of Science through July 2025, ultimately including 12 studies from 733 screened articles. The evidence base included one large cohort of 18,386 participants alongside smaller randomized and observational trials. The review found that nausea, vomiting, diarrhea, and constipation were the most frequently reported GI symptoms, occurring predominantly with GLP-1 receptor agonists such as semaglutide and tirzepatide, particularly during dose escalation phases. Orlistat was commonly associated with steatorrhea and flatulence, while phentermine was linked to reduced GI motility. Newer investigational agents, including retatrutide and orforglipron, also demonstrated notable GI side effect profiles. Natural products and other investigational agents reported fewer adverse events but lacked long-term data and standardized reporting. Key limitations include heterogeneity in study designs and inconsistent GI outcome reporting across included studies. The authors concluded that GI side effects are common but generally mild to moderate, and that standardized reporting and proactive clinical management strategies may improve patient adherence and tolerability.
Medicina (Kaunas, Lithuania) · Nov 2025DOI ↗ Moderate · human
This systematic review and meta-analysis examined the risk of pancreatitis and pancreatic cancer associated with GLP-1 receptor agonists (GLP-1 RAs), including dulaglutide, exenatide, liraglutide, semaglutide, beinaglutide, retatrutide, and tirzepatide. Following PRISMA guidelines, the authors searched PubMed, Embase, and the Cochrane Library, ultimately including 62 randomised controlled trials encompassing 66,232 patients with a mean age of 58.3 years and a mean follow-up of approximately 43.5 weeks. The pooled analysis found a statistically significant increase in pancreatitis risk overall (RR: 1.44, 95% CI 1.09–1.89); however, this significance disappeared when results were stratified by background medication use, suggesting that concomitant medications may be a confounding factor. For pancreatic cancer, no significant overall association was identified (RR: 1.30, 95% CI 0.86–1.97), though a significant signal emerged in the subgroup taking background medications (RR: 1.85, 95% CI 1.05–3.26). The authors note this subgroup finding may be an artifact, as many excluded trials had zero events in both arms. Key limitations include variable follow-up durations, heterogeneous patient populations, and the influence of concomitant therapies, which complicate causal attribution to GLP-1 RAs alone.
Endocrinology, diabetes & metabolism · Sep 2025DOI ↗ Moderate · human
This systematic review and meta-analysis pooled data from 33 randomized controlled trials (n = 12,028 adults with overweight or obesity) to evaluate whether combining lifestyle modifications with GLP-1 receptor agonists (GLP-1RAs) produces greater improvements in body weight and cardiometabolic markers than lifestyle modification plus placebo. Searches covered PubMed, Embase, and the Cochrane Library through May 2025, and the protocol was pre-registered on PROSPERO. The study found that the combination therapy was associated with a statistically significant mean weight reduction of 7.13 kg, along with improvements in waist circumference, fat mass, systolic blood pressure, fasting blood glucose, glycated hemoglobin, total cholesterol, triglycerides, and LDL cholesterol. HDL cholesterol did not show a significant change. Subgroup analyses suggested that longer treatment duration, use of semaglutide or tirzepatide, weekly dosing, and trials conducted in North America were associated with larger weight loss effects. No included trials were rated high risk of bias. GRADE certainty ranged from low to high across outcomes, with heterogeneity and potential publication bias limiting confidence in several findings. The authors conclude that results should be interpreted cautiously given this variability in evidence certainty.
EClinicalMedicine · Aug 2025DOI ↗ Moderate · human
This systematic review and network meta-analysis evaluated the comparative efficacy and safety of dual and triple incretin-based agonists — compounds targeting combinations of GLP-1, GIP, and glucagon receptors — versus standard therapies for type 2 diabetes mellitus (T2DM). Researchers searched PubMed, Web of Science, Cochrane Library, and Embase through July 2024, identifying randomized controlled trials assessing outcomes including body weight, HbA1c, fasting blood glucose (FBG), adverse events (AEs), and serious adverse events (SAEs). The analysis found that Retatrutide (a triple agonist) was associated with the greatest weight reduction, while Tirzepatide (a dual GLP-1/GIP agonist) showed the largest reductions in both FBG and HbA1c. Regarding safety, Tirzepatide and Cotadutide were associated with increased AEs, whereas Semaglutide was associated with reduced SAEs. The authors suggest that receptor-specific targeting may help personalize T2DM treatment. Key limitations include small sample sizes in some included trials, short study durations, and reliance on indirect comparisons in the network meta-analysis. The authors acknowledge that direct head-to-head trials are needed to confirm these findings. The study was prospectively registered (PROSPERO: CRD42024532368).
Acta diabetologica · Jun 2025DOI ↗ Moderate · human
This systematic review and meta-analysis compared the weight-loss effectiveness of tirzepatide versus semaglutide in humans by searching PubMed, Scopus, and Web of Science through January 2025. From 751 initial records, seven studies were ultimately included — two randomized controlled trials (RCTs) and five retrospective cohort studies. Using a random-effects model in RStudio, the authors pooled mean differences (MDs) in body weight change between the two agents. The analysis found that tirzepatide was associated with statistically significantly greater weight loss compared to semaglutide (MD = 4.23 kg; 95% CI: 3.22–5.25). Subgroup analyses suggested that higher tirzepatide doses (>10 mg) and longer treatment durations (>6 months) were associated with progressively larger weight differences. Study quality was assessed using the Newcastle-Ottawa Scale for observational studies and the Cochrane Risk of Bias version 2 tool for RCTs; the authors reported high quality and low risk of bias overall. Publication bias was evaluated via forest plots and Egger's test. Limitations include the small number of included studies (only two RCTs), reliance on retrospective real-world data for most of the analysis, potential heterogeneity across study populations, and the possibility of residual confounding in the observational studies.
Journal of clinical medicine research · May 2025DOI ↗