Eli Lilly announced on 26 August 2026 that a real-world analysis of adults over 55 found lower healthcare costs among people who stayed on Zepbound (tirzepatide) than among matched untreated adults, and framed the result against the $195 monthly net price under Medicare’s GLP-1 Bridge programme. The underlying paper is peer-reviewed and published in Diabetes, Obesity and Metabolism. One detail governs everything else in it: the cost comparison excludes the price of the drug. These are savings elsewhere in the system that might offset what tirzepatide costs, not a reduction in what you pay for it.
What the analysis measured
The study drew on the Komodo Research Dataset for 8 November 2022 to 30 September 2025. It identified adults over 55 with obesity, or with overweight plus at least one weight-related comorbidity, and without type 2 diabetes, who started tirzepatide for weight management. Each was matched by propensity score to someone who never received an incretin-based therapy: 15,843 people per cohort. Changes in all-cause healthcare costs per person per month, excluding tirzepatide itself, were compared using a difference-in-differences framework.
Using inverse-probability-of-censoring weights, the difference was −$145 per month during the 6-to-12-month window (95% CI −$266 to −$25; a 12.3% reduction) and −$319 during 12-to-18 months (95% CI −$544 to −$94; 25.4%). A pairwise-censoring approach gave larger figures for the same windows: −$181 and −$607 (95% CI −$1,007 to −$207). Fewer inpatient and emergency department visits accounted for much of it, with an incidence rate ratio of 0.69 (95% CI 0.50 to 0.94) at 12 to 18 months. Note the spread between the two methods at the later window — $319 against $607 is close to a two-fold difference, and the wider interval runs from $207 to $1,007 a month. That is a real finding with a lot of imprecision attached, and the honest reading is “some offset, size uncertain.”
Where the press release and the paper diverge
Lilly’s release presents these numbers as savings “at six months” and “at 12 months.” The paper reports them as differences accruing across the 6-to-12 and 12-to-18-month windows. The figures are the same; the labels make the offset look as though it arrives roughly six months earlier than the published analysis describes. It is a small thing, but it is the kind of compression that matters when the release goes on to argue that savings cover the Bridge programme’s $195 monthly cost “beginning at six months.”
Three of the six authors are Eli Lilly employees, and the remaining three are at contract research organisations. That does not make the analysis wrong, but it does mean an interested party designed and announced it, and the framing serves a live commercial argument about Medicare and employer coverage. For a reader, none of this changes the number on the pharmacy receipt. Coverage and cash prices are still the thing that decides affordability, which is why we maintain a separate breakdown of what these drugs cost without insurance, and why the sourcing shortcuts people take when priced out — including compounded semaglutide — remain a live risk rather than a solved problem.
What is not yet known
This is matched claims data, not a randomised comparison. People who stay on an expensive injectable for 18 months are plausibly different from people who never start one in ways propensity scores cannot capture — more engaged with care, better resourced, healthier at baseline in unrecorded respects. The authors state directly that claims data do not capture tirzepatide’s net price, so the analysis cannot say whether treatment saves money overall; it can only size the non-drug offset. The cohort excluded people with type 2 diabetes, so the result does not transfer to them. And the follow-up stops at 18 months, which says nothing about whether the offset grows, holds, or disappears over the years someone would realistically stay on treatment.
Sources: Upadhyay N, Bonakdar A, Subedi K, Banerjee S, Behrend B, Hankosky ER. “Trends in Cost of Care With Tirzepatide in Adults Aged Over 55 Years With Obesity or Overweight Without Diabetes: A Matched Cohort Analysis.” Diabetes, Obesity and Metabolism, published online 24 August 2026 (doi:10.1111/dom.71250); Eli Lilly and Company, “Zepbound linked to lower healthcare costs in adults over age 55 according to a real-world study,” company news release, 26 August 2026.
