The compounding pharmacy tirzepatide lawsuits are a series of federal cases Eli Lilly began filing in 2024 and escalated through 2025 against pharmacies and telehealth companies selling compounded versions of the active ingredient in Mounjaro and Zepbound. Lilly’s core claims are false advertising under the Lanham Act and violations of state consumer-protection laws, brought after the FDA declared the two-year tirzepatide shortage resolved and closed the regulatory window that had allowed compounders to produce copies. Results so far are mixed: some claims have been dismissed, others are moving forward, and one case was thrown out on jurisdictional grounds.1FDA on unapproved GLP-1 drugs
Why Lilly Started Suing When It Did
Tirzepatide sat on the FDA’s official drug shortage list for roughly two years. That designation matters. Sections 503A and 503B of the Federal Food, Drug, and Cosmetic Act generally bar compounders from producing drugs that are “essentially copies” of FDA-approved medications, but those restrictions loosen when a drug is in shortage. State-licensed 503A pharmacies and larger 503B outsourcing facilities used that opening to build a substantial compounded-tirzepatide market, often selling at a fraction of the roughly $1,000-a-month brand-name price and sometimes adding ingredients like vitamin B12, glycine, or niacinamide to market the products as “personalized.”
The FDA first declared the shortage resolved on October 2, 2024. After a brief remand tied to litigation from the Outsourcing Facilities Association, the agency reaffirmed the decision on December 19, 2024. It then set enforcement-discretion deadlines: 503A pharmacies had until February 18, 2025, to stop compounding tirzepatide, and 503B facilities had until March 19, 2025.
Lilly’s suits are timed against that calendar. The company filed an early wave in June 2024 against compounders and medical spas in Colorado, the District of Columbia, Florida, Ohio, Texas, and Washington, focused on defendants it accused of falsely claiming to sell Lilly-manufactured tirzepatide. One of those cases, Eli Lilly & Co. v. Alderwood Surgical Center LLC in the Western District of Washington, produced a ruling on March 7, 2025, that has shaped everything since. The court threw out a state consumer-protection claim but let the federal trademark and false-advertising claims proceed, establishing that an FDA drug-shortage designation does not shield compounders from Lanham Act liability. The parties later notified the court of a settlement on August 4, 2025, though the judge sent the proposed consent judgment back for more information.
The Compounding Pharmacies Lilly Sued
On April 1, 2025, with the shortage over and the 503A deadline just past, Lilly filed against two of the largest compounders in the tirzepatide market.
Empower Pharmacy
In Eli Lilly and Co. v. Empower Clinic Services, LLC, Case No. 2:25-cv-02183 in the District of New Jersey, Lilly accused the Houston-based pharmacy of selling “Tirzepatide ODT,” an orally disintegrating tablet, and an injectable tirzepatide-niacinamide combination. Neither has been clinically tested or approved by the FDA. The complaint alleged Empower cited Lilly’s own Mounjaro and Zepbound clinical trial data to imply its products had been proven safe and effective, marketed mass-produced formulations as “personalized,” and had a history of sterility problems. Empower said publicly it was “committed to offering these life-changing formulations.”
On April 29, 2026, U.S. District Judge Sim Lake issued a mixed ruling. He dismissed the federal trademark claims, finding Lilly had not shown lost sales or irreparable harm, and dismissed the Texas unfair-competition allegations. But he allowed claims that Empower violated unfair-competition laws in other states to move forward, keeping the case alive.
Strive Pharmacy
In Eli Lilly and Co. v. Strive Pharmacy LLC, Case No. 1:25-cv-00401-SB in the District of Delaware, Lilly alleged the Arizona pharmacy sold a single standardized tirzepatide formulation mixed with vitamin B12 and glycine while advertising it as “specifically designed” for each patient’s “one-of-a-kind needs.” Strive said it would “vigorously defend” and called the suit “Big Pharma overstepping legitimate regulations.”
The case did not reach the merits. On October 8, 2025, Judge Bibas granted Strive’s motion to dismiss for lack of personal jurisdiction, holding that Lilly had not tied Strive’s online advertising to Delaware and that the pharmacy’s general commercial activity in the state was not enough. The dismissal was without prejudice, so Lilly can refile in Arizona or submit an amended complaint with stronger jurisdictional facts.
The Telehealth Platforms Lilly Sued
Three weeks later, on April 23, 2025, Lilly opened a second front against telehealth companies whose business models had grown up around prescribing and selling compounded tirzepatide. Four suits went out the same day.
- Eli Lilly and Co. v. Mochi Health Corp. et al., Case No. 3:25-cv-03534 (N.D. Cal.). Lilly alleged Mochi switched patients to compounded tirzepatide with different additives and altered dosages at least five times in eight months, reformulating repeatedly to stay ahead of regulatory restrictions.
- Eli Lilly and Co. v. Aios Inc. d/b/a Fella Health and Delilah et al., Case No. 3:25-cv-03535 (N.D. Cal.). Lilly accused Fella of selling unapproved oral tirzepatide in pill form and claiming it was superior to Lilly’s approved medicine.
- Eli Lilly and Co. v. Adonis Health Inc. d/b/a Henry Meds, Case No. 3:25-cv-03536 (N.D. Cal.). Lilly alleged Henry Meds improperly referenced Lilly’s clinical trials on its website and sold tirzepatide in a pill form the FDA has never approved.
- Eli Lilly and Co. v. Willow Health Services Inc., Case No. 2:25-cv-03570 (C.D. Cal.). Lilly accused Willow of falsely marketing a “cosmetic” GLP-1 product, a use with no FDA approval.
Against Mochi Health and Fella Health, Lilly added claims under California’s prohibition on the corporate practice of medicine, arguing the companies exercised “undue control” over prescribing decisions and manipulated dosages in ways that crossed from platform operation into unauthorized medical practice.
The Mochi case has produced the most substantive ruling so far. On April 20, 2026, U.S. District Judge Jacqueline Scott Corley denied the defendants’ motion to dismiss the Lanham Act and California Unfair Competition Law claims, finding Lilly had plausibly alleged injury, but granted the motion on a civil-conspiracy count for failure to show the defendants conspired among themselves. The core false-advertising and unfair-competition claims are moving forward. Public reporting on the status of the Willow, Fella, and Henry Meds cases is thin.
The Safety Argument Lilly Is Making
Lilly’s public case against compounders leans heavily on patient safety, and one specific data point has become central: an impurity the company says forms when tirzepatide is combined with vitamin B12, one of the most common compounder additives.
Lilly published the underlying research as a pre-print in March 2026, and the study appeared in Expert Opinion on Drug Safety in April 2026. Researchers, all Lilly employees, tested ten compounded tirzepatide-B12 samples obtained from pharmacies, medical spas, and telehealth networks. They identified a previously unknown tirzepatide-B12 adduct at levels up to 10% of total polypeptide content, formed through a ligand substitution reaction, with structural changes to the tirzepatide molecule that could affect how the drug binds its target receptors. The authors acknowledged there is no evidence yet on whether the impurity affects safety or efficacy in humans, and critics have noted the study received no external funding and had no independent authors. Lilly has urged the FDA to recall compounded tirzepatide products containing B12.
Broader adverse-event data sits alongside that finding. As of December 2025, the FDA’s Adverse Event Reporting System had logged at least 455 reports tied to compounded tirzepatide, including 339 classified as serious and 8 deaths. By May 2026, adverse-event reports for compounded semaglutide and tirzepatide combined had passed 1,700. Reported problems have included dosing errors from non-standardized measurements, inconsistent concentrations between batches, gastrointestinal complications, and hospitalizations for conditions like pancreatitis.
The FDA has run a parallel enforcement track. It issued warning letters to individual compounders in early 2024, then roughly 80 warning letters and 40 untitled letters in September 2025 to online sellers of compounded GLP-1 medications, another 30 warning letters in March 2026, and 25 more during the week of June 15, 2026. The letters have targeted labeling compounded drugs as “generic,” calling them “clinically proven,” suggesting the FDA “licenses” compounding pharmacies, and using “same active ingredient” language to imply therapeutic equivalence with branded drugs. CDER Acting Director Michael Davis said compounded GLP-1 products have not undergone the “rigorous review for safety, efficacy, and manufacturing quality” required for FDA-approved drugs.
What’s Still Open
Tirzepatide no longer appears on the FDA’s drug shortage list or the 503B bulks list, and the enforcement-discretion periods have expired. Separately, the Outsourcing Facilities Association’s challenge to the FDA’s shortage determination is pending before the Fifth Circuit as Case No. 25-10600, with Lilly participating as an intervenor-appellee supporting the FDA. Judge Mark Pittman denied the OFA’s preliminary injunction on March 5, 2025, holding the FDA’s shortage-list decisions are informal adjudications rather than substantive rules requiring notice-and-comment rulemaking.
Industry observers expected the initial six suits to be followed by “dozens” more, and Lilly signaled it intended to send cease-and-desist letters to roughly fifty additional entities. The company has said publicly that “anyone continuing to sell mass compounded tirzepatide is breaking the law and deceiving patients” and has pledged to “continue to take action to stop those who threaten patient safety.”