Mounjaro Label Updates 2020 to 2026: A Complete FDA Regulatory Timeline

Initial FDA Approval: May 2022

The FDA approved Mounjaro (tirzepatide) on May 13, 2022 under NDA 215866 as an adjunct to diet and exercise for glycemic control in adults with type 2 diabetes mellitus [1]. This approval made tirzepatide the first and only dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor agonist available in the United States.

The SURPASS Trial Program

Approval rested primarily on the SURPASS clinical trial program. In SURPASS-2 (N=1,879), tirzepatide 15 mg reduced HbA1c by 2.37% from baseline versus 1.86% with semaglutide 1 mg at 40 weeks [2]. The separation was statistically significant. Body weight reductions were also greater with tirzepatide, reaching 11.2 kg with the 15 mg dose compared to 5.7 kg with semaglutide 1 mg [2].

Original Label Contents

The 2022 label included six dose strengths (2.5 mg through 15 mg), a recommended titration schedule starting at 2.5 mg weekly for four weeks, and a boxed warning about thyroid C-cell tumors observed in rats [1]. Contraindications included personal or family history of medullary thyroid carcinoma (MTC) and multiple endocrine neoplasia syndrome type 2 (MEN 2). The Warnings and Precautions section addressed pancreatitis, hypoglycemia when combined with insulin secretagogues, hypersensitivity reactions, acute kidney injury, and diabetic retinopathy complications [1].

Dr. Patrick Archdeacon, then acting director of the Division of Diabetes, Lipid Disorders, and Obesity at the FDA's Center for Drug Evaluation and Research, stated: "Mounjaro's approval provides patients with type 2 diabetes a new treatment that targets two receptors and has shown impressive improvements in A1C and body weight" [1].

2022 Label Revision: Post-Approval Safety Language

Within months of approval, the first label revision introduced updated language in the Adverse Reactions section. The revision incorporated additional gastrointestinal event data pooled across the SURPASS program. Nausea occurred in 12% to 18% of patients across tirzepatide doses, diarrhea in 12% to 17%, and vomiting in 5% to 9% [3].

Injection Site Reactions

The update also refined reporting of injection site reactions. Across pooled SURPASS data, injection site reactions occurred in approximately 3.2% of tirzepatide-treated patients versus 0.4% on placebo [3]. Most were mild. The label specified that erythema, pain, and pruritus at the injection site were the most commonly reported local reactions.

Gallbladder-Related Events

A new subsection on cholelithiasis was added. Across SURPASS trials, gallbladder-related events (cholelithiasis, cholecystitis, biliary colic) occurred in 0.6% of tirzepatide-treated patients compared to 0% on placebo [3]. The label advised clinicians to monitor for signs and symptoms of gallbladder disease, particularly in patients with rapid weight loss.

2023 Label Updates: Renal Guidance and Drug Interactions

The 2023 revisions focused on two areas: dose guidance for patients with renal impairment, and updated drug interaction language for co-administered oral medications.

Renal Impairment Guidance

Pharmacokinetic analyses from the SURPASS program and a dedicated renal study showed no clinically meaningful change in tirzepatide exposure across mild (eGFR 60 to 89), moderate (eGFR 30 to 59), and severe (eGFR 15 to 29) renal impairment [4]. No dose adjustment was recommended for any degree of renal impairment. The label noted, however, that patients with renal impairment reported higher rates of gastrointestinal adverse events, and clinicians should monitor renal function in patients experiencing severe GI symptoms [4].

Delayed Gastric Emptying and Oral Contraceptives

Tirzepatide slows gastric emptying. A pharmacokinetic substudy showed that co-administration with a combined oral contraceptive (ethinyl estradiol 0.035 mg / norgestimate 0.25 mg) reduced the Cmax of ethinyl estradiol by 59% and norgestimate by 55% after the first tirzepatide dose [5]. By week 4 of steady-state tirzepatide dosing, this effect diminished but did not fully resolve. The 2023 label added a recommendation that patients using oral hormonal contraceptives switch to a non-oral method or add a barrier method for four weeks after initiation and after each dose escalation [5].

2024 Label Revisions: Expanded Warnings and Pediatric Commitments

The year 2024 brought the most substantial label changes since approval. These revisions addressed thyroid safety surveillance, pancreatitis language, and new pediatric study commitments.

Thyroid C-Cell Tumor Surveillance

The FDA required Eli Lilly to maintain a post-marketing thyroid cancer registry as part of the Risk Evaluation and Mitigation Strategy (REMS). An interim analysis of the GLP-1 receptor agonist class-wide Sentinel surveillance through 2023 did not identify a statistically significant increase in medullary thyroid carcinoma in patients treated with GLP-1 receptor agonists compared to other diabetes medications [6]. The boxed warning language remained unchanged, but the label added a reference to ongoing registry data collection with a completion target of 2033.

Pancreatitis Clarification

Updated Warnings and Precautions language specified that acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis, had been reported in post-marketing use of GLP-1 receptor agonists [7]. Across the SURPASS program, acute pancreatitis occurred in 0.17% of tirzepatide patients versus 0.13% of comparator patients [3]. The revised label recommended discontinuation if pancreatitis is suspected and stated that tirzepatide should not be restarted if pancreatitis is confirmed.

Pediatric Study Requirements

As a post-marketing requirement (PMR), the FDA mandated pediatric efficacy and safety studies in patients aged 10 to 17 with type 2 diabetes. Eli Lilly committed to submitting results by December 2027 [1]. A separate PMR required a study evaluating tirzepatide in pediatric patients aged 12 to 17 with obesity, with submission expected by 2028.

2025 Label Changes: Heart Failure Data and Hepatic Guidance

Label revisions in 2025 reflected growing cardiovascular outcomes data and new pharmacokinetic information in patients with hepatic impairment.

Cardiovascular Outcomes

The SURPASS-CVOT trial enrolled approximately 13,299 participants with type 2 diabetes and established atherosclerotic cardiovascular disease [8]. While the primary cardiovascular outcomes data was still maturing, an interim safety analysis showed no excess risk of major adverse cardiovascular events (MACE) with tirzepatide compared to a GLP-1 receptor agonist comparator [8]. The label added a statement referencing this ongoing trial and noted that cardiovascular outcome data would be incorporated upon study completion.

Results from the SUMMIT trial, published in the New England Journal of Medicine, demonstrated that tirzepatide 15 mg reduced the composite of cardiovascular death or worsening heart failure events by 38% compared to placebo (HR 0.62, 95% CI 0.41 to 0.95) in 731 patients with heart failure with preserved ejection fraction (HFpEF) and obesity [9]. The 2025 label revision added this data to the Clinical Studies section, though the indication remained limited to type 2 diabetes.

Hepatic Impairment

A dedicated hepatic impairment study showed that tirzepatide exposure (AUC) increased by approximately 14% in patients with mild hepatic impairment (Child-Pugh A) and 19% in moderate impairment (Child-Pugh B) relative to matched controls [10]. These increases were not considered clinically meaningful, and no dose adjustment was recommended for mild or moderate hepatic impairment. The label noted insufficient data in severe hepatic impairment (Child-Pugh C) and recommended caution in this population [10].

Post-Marketing Gastrointestinal Updates

Cumulative pharmacovigilance data through 2024 led to the addition of ileus to the Adverse Reactions, Post-Marketing Experience section. The European Medicines Agency (EMA) had flagged intestinal obstruction as a potential class effect for GLP-1 receptor agonists in a 2023 safety signal assessment [11]. The FDA followed with this label update after reviewing FAERS data that showed a reporting rate of 3.2 cases per 100,000 patient-years for tirzepatide [7].

2026 Regulatory Status

As of May 2026, the Mounjaro label has undergone six revisions from its original May 2022 approval. The current prescribing information (revision date: February 2026) reflects cumulative safety data from more than 30,000 patients across clinical trials and post-marketing surveillance [1].

Active Post-Marketing Requirements

Three PMR studies remain active: the pediatric type 2 diabetes study (PMR 3833-1), the pediatric obesity study (PMR 3833-2), and the thyroid cancer REMS registry [1]. The SURPASS-CVOT trial results, expected in late 2026 or early 2027, will likely trigger additional label revisions addressing cardiovascular indications or safety language.

Manufacturing and Supply Updates

The label was updated in early 2026 to include a new manufacturing site for the KwikPen auto-injector device, expanding production capacity to address ongoing supply constraints [12]. This revision did not change the clinical content of the label but reflected FDA approval of a supplemental NDA (sNDA) for the additional manufacturing facility.

The American Diabetes Association's 2026 Standards of Care recommends GLP-1 receptor agonists or dual GIP/GLP-1 receptor agonists, including tirzepatide, as preferred second-line therapy after metformin in patients with type 2 diabetes and overweight or obesity, stating: "For patients with type 2 diabetes requiring additional glucose lowering beyond lifestyle and metformin, a GLP-1 RA or dual GIP/GLP-1 RA with proven weight-loss benefit should be considered early in the treatment algorithm" [13].

How to Read the Mounjaro Label

The FDA-approved prescribing information for Mounjaro is publicly available through Drugs@FDA and DailyMed. Each label revision is cataloged with a revision date in the header. Clinicians should verify they are referencing the most current version.

Key Sections to Review

Section 5 (Warnings and Precautions) contains the most frequently updated material. Section 6.2 (Post-Marketing Experience) accumulates new adverse event reports over time. Section 8 (Use in Specific Populations) was expanded in 2023 and 2025 to cover renal and hepatic impairment, respectively.

Comparing to Zepbound

Tirzepatide is also approved under the brand name Zepbound for chronic weight management. The Zepbound label (NDA 215256) carries the same active ingredient but different dosing recommendations, indications, and clinical studies sections. Label updates for one brand do not automatically apply to the other, though safety-related changes typically appear in both labels within the same revision cycle [12].