MHRA dismantles what it calls the world's largest unlicensed weight-loss drug factory

Britain's Medicines and Healthcare products Regulatory Agency (MHRA) said in October 2025 that it had dismantled a factory in central England that it called the country's first illicit weight-loss medicine manufacturing site [2]. Investigators seized 2,000 injection pens labeled as containing tirzepatide, the active ingredient in Eli Lilly's Mounjaro and Zepbound, along with products labeled retatrutide, an experimental obesity drug that is still in clinical trials and not approved for sale anywhere [2]. Tens of thousands of empty pens and raw chemicals were also confiscated [2].

UK health minister Wes Streeting called the raid "a victory in the fight against the shameless criminals who are putting lives at risk by peddling dangerous and illegal weight-loss jabs to make a quick buck," adding that the seized products were "made with no regard for safety or quality" and posed a major risk to buyers [2].

The MHRA followed up in February 2026 with a second operation, raiding two sites in Lincolnshire and Nottinghamshire and seizing almost 2,000 more doses along with manufacturing equipment, packaging materials, and commercial vehicles ^[1]. Those products were again labeled as tirzepatide and retatrutide ^[1]. Reuters reported that the back-to-back raids reflect a broader pattern of criminal networks exploiting surging global demand for weight-loss drugs by selling counterfeit or unregulated injectables online and through underground channels ^[1].

The MHRA has linked demand for illegal products partly to access limits within Britain's National Health Service, which restricts weight-loss prescriptions to patients meeting specific medical criteria, pushing others toward private prescriptions that can cost hundreds of pounds a month [2].

Why it matters for patients

None of the seized products were licensed medicines. There is no way to verify what was actually inside pens labeled tirzepatide or retatrutide, since they came from unregulated manufacturing operations rather than approved pharmaceutical supply chains ^[1][2]. Retatrutide in particular is not approved for any use anywhere in the world; it remains in clinical trials, so any product sold under that name outside a trial setting is not a legitimate medicine [2].

This is a UK enforcement story, but the underlying problem — counterfeit and gray-market GLP-1 and related injectables sold online — is not confined to Britain. The same surge in demand for drugs like semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro, Zepbound) that has strained legitimate supply chains has also created an opening for unregulated sellers marketing look-alike products. Products from unlicensed factories carry unknown risks, including wrong dosing, contamination, or ingredients that do not match the label at all.

What happens next

In the United States, FDA Commissioner Marty Makary said on social media that the agency is expected to act against copycat drugs marketed as alternatives to approved obesity therapies, signaling potential enforcement against unapproved products sold at scale ^[1]. The MHRA's two operations within four months suggest UK authorities intend to keep targeting illegal manufacturing and distribution networks as the obesity-drug market keeps growing ^[1]. No timeline has been given for further raids or for any coordinated US-UK enforcement action, and neither agency has released additional detail on how the seized products were being distributed or sold to consumers.