CVS Caremark Reverses Zepbound Exclusion: What a PBM's U-Turn Reveals About Who Really Controls Your Prescriptions

On May 28, 2026, CVS Caremark announced it would add Eli Lilly's blockbuster obesity injection Zepbound (tirzepatide) back to its standard commercial formulary as a preferred option, effective October 1 [1]. The decision reverses a controversial July 2025 exclusion that stripped coverage from an estimated 200,000 patients [2] and drew a class-action lawsuit, widespread physician opposition, and sustained public pressure. Alongside the Zepbound restoration, CVS will also cover Lilly's new oral GLP-1 obesity pill Foundayo (orforglipron) starting June 1 [1].

The move ends a 15-month standoff that became the highest-profile test case of pharmacy benefit manager (PBM) formulary power in the GLP-1 era. But the resolution raises as many questions as it answers: Was patient backlash the real catalyst, or did Eli Lilly simply sweeten its rebate offer enough to make CVS change course?

What Happened: The Exclusion and Its Fallout

CVS Caremark, the nation's largest PBM, dropped Zepbound from its commercial formulary on July 1, 2025, after reaching an exclusive deal with Novo Nordisk, the maker of rival GLP-1 drug Wegovy (semaglutide) [2]. Patients covered through employer plans using CVS Caremark were told to switch to Wegovy or pay out of pocket — between $299 and $449 per month depending on their Zepbound dose [3].

The class-action lawsuit filed on September 3, 2025, by plaintiffs Dennis Larkin and Danielle Gosline under the Employee Retirement Income Security Act (ERISA), alleged that CVS Caremark failed to make eligibility determinations in accordance with health plan documents and inadequately processed appeals [4]. The complaint estimated roughly 200,000 people lost Zepbound coverage [2].

For patients who could not afford to pay cash, the practical choice was switching to Wegovy — a drug that head-to-head clinical data shows produces less weight loss than Zepbound. For some, the disruption led to stopping treatment altogether. Research shows that GLP-1 discontinuation is consistently followed by rapid weight regain, typically within one year, and a decline in cardiometabolic benefits [5].

The Clinical Case: Zepbound and Wegovy Are Not Interchangeable

A central tension in the CVS Caremark controversy is whether Zepbound and Wegovy are close enough therapeutically that swapping one for the other is medically reasonable. The answer, based on head-to-head trial data, is nuanced.

The SURMOUNT-5 trial, a phase 3b randomized study published in the New England Journal of Medicine, directly compared tirzepatide (Zepbound) against semaglutide (Wegovy) in adults with obesity who did not have diabetes. At 72 weeks, Zepbound produced an average body weight reduction of 20.2%, compared to 13.7% for the standard-dose Wegovy (2.4 mg) and 18.7% for the higher 7.2 mg dose [6]. Zepbound also reduced waist circumference more (18.4 cm vs. 13.0 cm) and showed greater improvement in systolic blood pressure [6].

Source: NEJM / Eli Lilly SURMOUNT-5 Trial

Data as of May 14, 2025CSV

The mechanism explains the gap. Both drugs mimic the GLP-1 hormone, which regulates appetite and blood sugar. But Zepbound also mimics a second gut hormone, GIP (glucose-dependent insulinotropic polypeptide), giving it a dual mechanism of action [7]. Whether that difference is clinically significant enough to justify patient choice over formulary substitution is the core policy question.

From a cardiovascular standpoint, both drug classes have demonstrated meaningful benefits. A Mass General Brigham analysis of over 90,000 patients with heart failure found that GLP-1 medications were associated with a greater than 40% reduction in heart failure hospitalization or all-cause mortality [8]. Semaglutide and tirzepatide showed similar effectiveness in reducing heart failure hospitalization risk in data published in JAMA [8]. A separate Aon analysis found that female GLP-1 users experienced a 47% reduction in hospitalizations for major adverse cardiovascular events compared to non-users [9].

The Deal Behind the Deal

CVS Caremark framed the Zepbound restoration as the result of "successful continued pricing negotiations" with both Lilly and Novo Nordisk [1]. Under the new arrangement, both companies' GLP-1 medications will be co-preferred options on CVS Caremark's standard commercial formulary template, which covers 25 million to 30 million Americans [1]. Eligible patients with commercial insurance could pay as little as $25 per month for either Zepbound or Wegovy [1].

The specific financial terms — rebate levels, volume commitments, price concessions — remain confidential, as is standard in PBM-manufacturer negotiations. What is publicly visible is the outcome: Lilly has been placed on "equal footing" with Novo Nordisk on CVS's formulary, a significant shift from the exclusive arrangement CVS had with Novo [10].

The timing of the announcement is also notable. It coincides with Lilly's launch of Foundayo, its oral GLP-1 pill. CVS's decision to cover Foundayo immediately upon launch — waiving its usual new-to-market block — suggests that the Zepbound restoration was part of a broader commercial agreement between CVS and Lilly rather than a standalone response to patient pressure [10].

Plan sponsors (employers and insurers) who adopt CVS Caremark's standard formulary can still opt out of covering GLP-1s for weight loss entirely, meaning coverage is not guaranteed for all patients under CVS Caremark plans [1].

The Precedent Question: Has This Happened Before?

CVS Caremark's Zepbound reversal is not unprecedented. In January 2022, CVS excluded apixaban (Eliquis), a widely used blood thinner, from its commercial formulary in favor of rivaroxaban (Xarelto). The move triggered what researchers described as "an unprecedented outpouring of opposition from patients, physicians, and medical nonprofits" [11]. By July 2022, CVS reversed course, citing "a significant reduction in manufacturer pricing" — language strikingly similar to the Zepbound explanation [12].

The pattern is consistent: public outcry provides political cover, but the actual reversal mechanism appears to be a renegotiated manufacturer contract. In both the Eliquis and Zepbound cases, the PBM attributed its change of position to improved pricing rather than acknowledging that the original exclusion was medically problematic.

The broader context reinforces this interpretation. By 2020, the three largest PBMs combined excluded 1,195 medications from their national formularies, a figure that has continued to grow [13]. Reversals remain rare. The FTC has launched an investigation into PBM practices, and Congress has considered legislation to regulate formulary exclusions [13]. But for now, PBMs retain broad discretion over which drugs are covered, with manufacturer rebates — not clinical evidence — often serving as the primary decision variable.

The Cost Equation: Do GLP-1s Pay for Themselves?

For employers weighing whether to cover GLP-1 obesity drugs, the math is genuinely uncertain. At roughly $550 per month list price (before rebates), the upfront cost is significant. Only about 23% of employers offered GLP-1 coverage for weight loss as of 2025, up from 18% in 2023 [14].

Source: KFF/SHRM Employer Benefits Surveys

Data as of Dec 1, 2025CSV

However, emerging evidence suggests that sustained GLP-1 use may reduce total medical spending over time. An Aon analysis of more than 192,000 GLP-1 users across 50 million commercially insured lives found that while medical costs increased during the first year of treatment, cost growth slowed considerably afterward: a 3% increase in medical cost growth over 18 months for GLP-1 users versus 9% for a control group [9]. Diabetes patients adhering to GLP-1s saw medical costs drop 6% to 9% after 30 months [9].

Hospitalizations for major adverse cardiovascular events dropped by 37% over two years after patients started GLP-1 medications [9]. Given that cardiovascular disease, diabetes complications, and obesity-related hospitalizations represent some of the largest cost drivers in employer health plans, these reductions are economically meaningful — though the evidence base is still maturing and relies largely on observational data.

The Employee Benefit Research Institute (EBRI) has modeled the impact of GLP-1 coverage on employer premiums, finding that the cost depends heavily on utilization rates and the extent to which downstream savings materialize [15].

The Access Gap: Who Can Actually Get These Drugs?

The CVS Caremark reversal affects a slice of the population — commercially insured patients whose employers use CVS Caremark and choose to cover GLP-1s for obesity. The broader picture of GLP-1 access in the United States remains stark.

About 40% of American adults — over 100 million people — meet the clinical definition of obesity [16]. Yet only a fraction have insurance coverage for GLP-1 weight loss medications. As of January 2026, only 13 states covered GLP-1s for obesity through Medicaid [17]. Among those currently using GLP-1 drugs, about 27% of insured users reported paying the full cost themselves [18].

Source: WHO Global Health Observatory

Data as of Dec 31, 2024CSV

A new Medicare Bridge program, launched in mid-2026, allows Medicare beneficiaries to access GLP-1 prescriptions for weight loss at $50 per month, extended through December 2027 [19]. But this remains a stopgap, not permanent coverage.

International Comparison: A Global Patchwork

The U.S. is not alone in struggling with GLP-1 coverage policy, but it does face uniquely high costs. Net prices for Wegovy in the United States run approximately $8,000 to $9,000 per year, compared to $2,232 in Denmark, $1,680 in Germany, and $1,104 in the United Kingdom [20].

Source: The Lancet / Becarispublishing

Data as of Jan 1, 2025CSV

Coverage varies widely. The UK's National Institute for Health and Care Excellence (NICE) has approved Wegovy and Mounjaro (the UK brand name for tirzepatide for diabetes) for patients meeting BMI and comorbidity thresholds, though access through the National Health Service remains constrained by capacity [20]. Germany's statutory insurance system excludes weight management drugs from public reimbursement by law, though GLP-1s are covered for patients with both obesity and diabetes [20]. Canada's drug evaluation agency has used cost-effectiveness recommendations to limit public coverage [20].

A Lancet study examining GLP-1 eligibility across 99 countries found that coverage policies are tied almost universally to BMI cutoffs and the presence of comorbidities, with wide variation in which conditions qualify [21].

The Steelman Case for Formulary Exclusion

CVS Caremark's original decision to exclude Zepbound had a defensible actuarial logic, even if it proved politically unsustainable.

When two drugs in the same therapeutic class produce broadly similar outcomes — and the SURMOUNT-5 data, while favoring Zepbound, showed both drugs producing clinically significant weight loss — a PBM can negotiate steeper rebates by granting one manufacturer preferred status. Those rebates, in theory, reduce costs for plan sponsors, which can translate to lower premiums for the majority of covered employees who never use obesity drugs.

From a fiduciary standpoint, an employer-sponsored plan has obligations to all its members, not just those taking any particular medication. If an exclusive Novo Nordisk deal saved plan sponsors measurable money on per-member costs, the PBM could argue it was fulfilling its role as a cost-management intermediary — the very function PBMs were created to serve.

The counterargument is that this model treats drugs as commodities rather than individualized treatments. A patient who has responded well to Zepbound and faces forced substitution to Wegovy may experience different side effects, different efficacy, or — most concerning — may discontinue treatment entirely. Real-world discontinuation rates for GLP-1s are already high: 46.5% among diabetes patients and 64.8% among those without diabetes, driven primarily by cost and gastrointestinal side effects [5]. Forcing a switch adds another discontinuation risk factor on top of already fragile adherence.

The Bigger Picture: PBMs Under Scrutiny

Source: OpenAlex

Data as of Jan 1, 2026CSV

The explosion of research interest in GLP-1 medications — over 13,000 papers published on GLP-1 and obesity in 2025 alone — reflects the scale of the clinical opportunity and the commercial stakes. The GLP-1 market is projected to exceed $100 billion in annual sales within the next few years, making formulary decisions among the most consequential in the pharmaceutical supply chain.

The CVS Caremark Zepbound episode has become a reference point in the ongoing federal debate over PBM regulation. The FTC's investigation into PBM practices, launched in 2024, is examining whether the rebate-driven formulary model harms patients by prioritizing manufacturer payments over clinical value [13]. Congressional proposals have sought to increase transparency around rebate negotiations and limit the ability of PBMs to exclude drugs from formularies when clinically superior alternatives exist.

CVS Caremark's reversal may satisfy patients in the short term. But it does not resolve the structural question at the heart of the GLP-1 access crisis: in a system where a PBM can remove a clinically superior drug from coverage, pressure a manufacturer into larger rebates through patient disruption, and then restore the drug while claiming credit for "affordability," who is the system actually serving?

The 200,000 patients who lost Zepbound coverage for 15 months would likely have a clear answer. Whether policymakers arrive at the same conclusion remains to be seen.