Inspectors at the Food and Drug Administration found “gross contamination” at two factories in China that make components for GLP-1 weight-loss drugs — including mold and bug infestations, according to an explosive report.

Both facilities were operated by so-called compounding pharmacies that produce semaglutide and tirzepatide — the active ingredients in blockbuster weight-loss drugs from Novo Nordisk and Eli Lilly — for black-market versions of the drugs that aren’t approved for sale by safety regulators, according to Bloomberg.

At one facility operated by Chengdu Shengnuo Biopharm Co, inspectors found bugs in the ceiling along with moldy floors. When US inspectors arrived, employees were pouring out product samples into sinks in a “seemingly coordinated effort,” according to the report.

Alexander Raths – stock.adobe.com

Employees at the facility were also hastily moving documents out of a lab and into a room across the hall, stuffing them into lockers, which cited documents obtained under a Freedom of Information Act request. Inspectors added that they weren’t able to recover all the documents.

At another factory owned by Nanjing Chengong Pharmaceutical Co,, staff had been buying active ingredients made by other factories and slapping their own company’s seal of approval on them without reviewing testing and safety documentation, according to another report.

The two companies were put on the FDA’s import list, meaning their products could be confiscated at the border. The actual drugs themselves were not tested.

According to Bloomberg, one of the manufacturers, Chengdu Shengnuo Biopharm Co said in a filing with China’s government that it has been “diligently implementing effective measures” to correct the problems.

A doctor holds a syringe while preparing a GLP-1 injection for medical treatment in a laboratory. Piya W. – stock.adobe.com

The Post reached out to both labs in China and to the FDA. Neither immediately responded to requests for comment.

Michael Rogers, a former investigator with the FDA, told Bloomberg that the report findings “suggest a serious accident waiting to happen.” 

Compounded drugs are a part of a multibillion dollar industry of unregulated peptides, and according to the Wall Street Journal.

Little is known about the safety of unregulated peptides. The FDA is currently considering whether to allow compounding pharmacies overseas to produce different types of peptides. According to Bloomberg, some operate under the theory that US law allows the sale of copycats.

Nearly fifteen years ago, contaminated drugs — including a steroid shot for pain — from New England Compounding Pharmacy killed 64 people after infecting over 700 with meningitis.

Health Secretary Robert F. Kennedy, who oversees the FDA, has supported lifting restrictions on peptides.