Who knew that adding a vitamin to a knockoff weight-loss drug could turn regulatory evasion into personalized medicine? Apparently, some pharmaceutical compounders did. And they've built a business around it.
The shortage of FDA-approved GLP-1 medicines created an opening for compounders to meet legitimate patient needs. But shortages end, and so do the legal justifications that accompany them. For businesses determined to keep selling copies of blockbuster medicines, the solution was remarkably convenient: add a little vitamin B12 or B3, call the product customized, and carry on.
The FDA has a word for this maneuver: “pretextual.” That's a polite regulatory term for an excuse that doesn't pass the smell test.
On September 18, FDA issued a warning letter to Houston-based Empower Pharmacy identifying three products that appeared to be essentially copies of approved medicines. Two combined tirzepatide with vitamin B3, while another combined semaglutide with B12. The company maintained that these formulations addressed individual patient needs. FDA inspectors found reasons to question that explanation, including prescriptions that failed to document the required significant clinical difference and others containing identical justifications repeated across multiple patients. So much for individualized medicine.
Compounding is an essential part of American medicine. Patients sometimes need formulations that approved products cannot provide. Congress recognized that reality. It did not authorize a parallel industry manufacturing knockoffs of commercially available drugs while avoiding the regulatory obligations imposed on the companies that developed them. That distinction matters. And it is being deliberately blurred.
The compounding exemption is based on medical necessity, not marketing ingenuity. A physician's determination that a particular patient needs a modified formulation is a clinical judgment. It isn't supposed to be boilerplate language that can be reproduced across hundreds of prescriptions to justify industrial-scale production.
The FDA's findings concerning Empower went well beyond questionable paperwork. Inspectors also identified insanitary conditions under which supposedly sterile products may have become contaminated. This does not establish that individual vials were contaminated, but it raises serious questions about manufacturing controls for medicines intended to be injected directly into patients.
There is some history here. FDA warned Empower's outsourcing facility in April 2025 about deficiencies in sterile-drug production. In July 2025, the Center for Medicine in the Public Interest published my report examining ingredient-quality concerns and a recall of more than 8,000 testosterone vials over sterility issues. At the time, I argued that FDA needed to confront the growing practice of dressing up mass-produced copies as personalized medicine. The September warning letter suggests the problem has not gone away.
Patients, meanwhile, are left to figure out which products have actually met FDA standards and which haven't. Too often, the marketing makes that distinction almost impossible. A National Consumers League survey found that 71 percent of women surveyed believed compounded GLP-1 products had to be tested and proven safe before they could be sold. That belief is wrong. Compounded medicines do not undergo FDA premarket review for safety, effectiveness, and quality.
A study published in JAMA Health Forum examined 79 websites offering compounded GLP-1 products. Fewer than half disclosed that the medicines lacked FDA approval. More than a third stated or implied that they were approved.
Imagine that. Patients believe they're purchasing medicines that have met federal approval standards, while some sellers are doing precious little to correct the misunderstanding. In certain cases, they're making it worse. This cannot end with one pharmacy and one warning letter. FDA cannot defend the integrity of its drug approval system while allowing exceptions to become profitable substitutes for compliance.
FDA approval isn't a paperwork exercise. It requires clinical evidence, manufacturing discipline, regulatory scrutiny, and substantial financial risk. Companies don't get to skip those obligations simply because they've found a more profitable business model.
Compounding serves a different purpose and operates under a different legal framework. It was never intended to offer an easier route to the same mass market. Yet that is precisely the opportunity created when regulators tolerate flimsy claims of individualized treatment.
Regulatory arbitrage is one thing. Turning FDA approval into an optional expense is quite another. If trivial formulation changes become a way around restrictions on copying approved drugs, patients assume risks they may not understand. Legitimate compounders get undercut. And companies that invest in clinical evidence are left wondering why they bothered playing by the rules.
FDA deserves credit for confronting Empower's vitamin alibi. But identifying a violation and changing commercial behavior are two very different things. Warning letters have their place. They are not an enforcement strategy by themselves.
The agency gave Empower 15 working days from receipt of the letter to explain how it would address the cited violations. That response deserves careful scrutiny. If violations persist, FDA should be prepared to pursue seizures and injunctions, with Justice Department involvement where appropriate. If evidence warrants criminal investigation, the agency should follow it.
Nor should Empower be treated as an isolated case. Every compounder selling modified versions of approved GLP-1 medicines should understand that adding a vitamin doesn't confer regulatory immunity. The relevant question is whether the modification produces a significant difference for an identified patient, supported by an actual prescribing determination. A marketing department cannot make that judgment, and a rubber-stamp prescription should not be allowed to substitute for it.
FDA has spent decades insisting, correctly, that pharmaceutical claims require evidence. That principle shouldn't disappear because a product is popular, profitable, or promoted under the fashionable banner of personalized medicine.
FDA knows what's going on. The question is whether it has the appetite to stop it. Until violating the law becomes more expensive than obeying it, the vitamin alibi will remain a profitable business model.
Peter J. Pitts, a former FDA Associate Commissioner, is President of the Center for Medicine in the Public Interest.
