Patients file an ERISA class action over the Zepbound formulary removal
Two patients sued CVS Caremark in federal court on Sept. 3, saying its July 1 switch from Zepbound to Wegovy was driven by a Novo Nordisk rebate deal and violated ERISA.
Two people who lost coverage for Zepbound (tirzepatide) filed a proposed class-action lawsuit against Caremark RX, L.L.C., doing business as CVS Caremark, on Sept. 3, 2025, in the U.S. District Court for the Southern District of New York [1]. The complaint alleges that the pharmacy benefit manager dropped Zepbound from its formularies because of a rebate agreement with Novo Nordisk for Wegovy (semaglutide), not because of clinical evidence, and that doing so breached its fiduciary duties under the Employee Retirement Income Security Act (ERISA) [1][3].
Caremark announced earlier in 2025 that it would remove Eli Lilly's Zepbound from its standard control, advanced control and value formularies effective July 1, giving preferred status to Wegovy and arguing the two drugs are interchangeable [2]. CNN reported the change applies to Caremark's most common formulary template, covering roughly 25 million to 30 million people [3]. The complaint says that in 2024 CVS Caremark handled about 27% of all pharmacy benefit claims for the more than 154 million people covered by employer-sponsored plans [1].
What the two patients say happened
Dennis Larkin of Mahopac, New York, is covered by a self-funded plan sponsored by his employer, Publicis [1]. He was prescribed Zepbound in December 2023 for weight management and was diagnosed with severe obstructive sleep apnea on April 22, 2024 [1]. His employer moved to Caremark effective Jan. 1, 2025; Caremark approved his Zepbound coverage that January and he refilled it until June 19, 2025, when the plan said Zepbound was no longer covered [1]. His first-level appeal was filed and denied on July 14, a second-level appeal was denied July 23, and an external review denial arrived July 25 [1]. The denial letter said "current plan approved criteria and current medical literature do not support the use of Zepbound over the available formulary alternatives" and that "[t]he primary covered drug for [his] plan is Wegovy" [1]. After switching, he took his first Wegovy dose Aug. 9 and his second Aug. 16, and the complaint says he experienced a return of gastroesophageal reflux disease, stomach pain, hunger and weight gain [1].
Danielle Gosline of Auburn, New York, was prescribed Zepbound on Jan. 3, 2024 for obesity [1]. Caremark approved a new prior authorization on April 1, 2025 that the complaint says was supposedly valid through April 1, 2026, but coverage was denied on July 1, 2025, and her appeal was denied July 8 as "not medically necessary" [1].
The complaint stresses that the two drugs are different molecules and argues they are "not clinically interchangeable" because of "different methods of action, different clinical outcomes, and different side effects for individual patients" [2][3]. It also notes that Zepbound became the first and only FDA-approved drug for moderate-to-severe obstructive sleep apnea in adults with obesity on Dec. 20, 2024, and that Wegovy does not carry that approval [1]. On its formulary page, CVS acknowledges studies suggesting greater weight loss with tirzepatide while saying "real-world evidence suggests the two are comparable" [2].
A Caremark spokesperson called the suit "without merit" and said the company will defend itself, adding that an exceptions process exists for rare cases where formulary options do not work or cause harmful side effects [2][3]. "Our formulary strategy maintains clinically appropriate coverage while using competition to drive lower costs," the spokesperson said [2][3].
Why it matters for patients
The case tests whether a PBM that decides appeals is acting as an ERISA fiduciary and whether rebate-driven formulary changes can be challenged in court [1]. The lawsuit asks for coverage of Zepbound to be restored for people on Caremark plans, plus other equitable relief [3].
The switch has already moved large numbers of prescriptions. An analysis of electronic health records by Truveta for CNN found about 1 in 10 Zepbound users switched to a different GLP-1 in July, roughly 16 times the usual rate, and more than 8 in 10 of those who stopped Zepbound moved to Wegovy [3]. New Zepbound prescriptions fell for the first time in nearly a year [3]. Endocrinologist Dr. Jody Dushay told CNN there is no simple one-to-one dose conversion between the two drugs, and that "when the dosing is not right, people may gain weight or plateau for a month and get frustrated" [3].
What happens next
Caremark has said it will fight the claims [2][3]. No hearing dates, class certification schedule or court rulings appear in the available sources, and the outcome is not yet known.
Sources
Semaglutides.org is for information only and is not medical advice. Always talk to a licensed healthcare provider about your own care. Some links to telehealth services are affiliate links, labeled where they appear.