FDA warning letters target marketers of unapproved weight loss drugs

In the latest tranche of published warning letters, the US Food and Drug Administration (FDA) has continued to go after drugmakers for marketing glucagon-like peptide-1 (GLP-1) receptor agonists and similar medications without regulatory approval. It also issued other warning letters for current good manufacturing Practices (CGMP) violations and failing to adhere to clinical trial protocols.

GLP agonist makers

On 7 April, the FDA published several warning letters, including a batch to companies that the agency said are marketing GLP-1 products, dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) products, and triple agonist (GLP-1/GIP/glucagon) products without regulatory approval. Over the past year, the agency has issued dozens of warning letters to companies for identical violations.

In the latest batch of warning letters to GLP manufacturers, the agency cited Prime Sciences, Lovega, Gram Peptides, FormPour, Guangzhou Huli Technology, Mile High Compounds, and PekCura Labs for marketing their products without FDA approval.

"These products are especially concerning from a public health perspective because injectable drug products can pose risks of serious harm to users, FDA wrote in its warning letter to Prime Sciences. "Injectable products are delivered directly into the body, sometimes directly into the bloodstream, and therefore, bypass some of the body’s key defenses against toxins and microorganisms that can lead to serious and life-threatening conditions.

"Despite statements on your product labeling marketing your products for ‘laboratory research purposes only’ and ‘not for human consumption, medical use or veterinary use,’ evidence obtained from your website establishes that your products are intended to be drugs for human use," the agency wrote. "Your products are drugs as defined by section 201(g)(1) of the FD&C Act 21, U.S.C. 321(g)(1), because they are intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease and/or intended to affect the structure or function of the body."

FDA's letters to the other manufacturers are similar in their complaints about why their products fall under the agency's regulatory oversight and why the companies are not allowed to market them, despite their oft-cited claims that the products, especially the triple agonists, are for research only.

All the GLP companies in question also market their products online, either through their own websites or on sites such as eBay.

"Your 'Googeer GLP-1 Weight Control Oral Solution' product is a 'new drug' under section 201(p) of the FD&C Act, 21 U.S.C. 321(p), because it is not generally recognized as safe and effective (GRASE) for use under the above-described conditions prescribed, recommended, or suggested in the labeling," said FDA in their letter to Guangzhou Huli based in Chicago. "With certain exceptions not applicable here, a new drug may not be introduced or delivered for introduction into interstate commerce without an approved application from FDA in effect, as described in section 505(a) of the FD&C Act, 21 U.S.C. 355(a).

"No approved application pursuant to section 505 of the FD&C Act, 21 U.S.C. 355, is in effect for this product," the agency wrote. "Accordingly, this product is an unapproved new drug."

Three of the companies, Prime Sciences, Lovega, and Gram Peptides, were also cited for marketing bacteriostatic water used to dilute the medication.

"Your firm offers 'Bacteriostatic Water' for sale alongside peptide products, which are drugs intended for injection and require reconstitution" said FDA in its letter to Lovega. "The sale of these products together demonstrates that you intend for your 'Bacteriostatic Water' to be used in combination for injection. Therefore, your 'Bacteriostatic Water' is a drug."

Prime Sciences, Lovega, Gram Peptides, FormPour, Guangzhou Huli Technology, Mile High Compounds, PekCura Labs

Medline Industries

FDA investigators issued a warning letter to medical device maker Medline Industries, which manufactures medical devices, including cardiovascular procedure kits that with NAMIC Angiographic Control Syringes and manifolds for injecting intra-arterial or intravenous radiographic contrast media. The agency said the company failed to meet CGMP requirements, including implementing and adhering to its risk-based corrective and preventive action (CAPA) procedures.

More specifically, the agency noted that Medline did not take appropriate CAPA in response to increased complaints in June 2023 regarding NAMIC Angiographic Control Syringes disconnecting from manifolds attributed to excess silicone.

"Your Health Hazard Evaluation (HHE) Qual-124366 dated June 11, 2024, determined the risk was low, which is inconsistent with your design failure modes and effectiveness analysis (dFMEA) (RA2022047; Rev. 4), which identified 'air embolism' as the highest severity issue for loose connections," FDA wrote. "Your firm’s corrective actions only included scrapping devices in inventory and increasing the cleaning frequency of the [redacted] machine to prevent excess silicone from migrating to the luer connector, despite receiving 221 complaints and filing 177 [medical device reports (MDR)] for the disconnection of the NAMIC Angiographic Control Syringes from manifolds which impact patients and clinicians, including one (1) MDR # 3015910259-2025-00109 involving the injection of air into a patient (Complaint # [redacted] dated [redacted]) and one (1) MDR # 3015910259-2024-00045 involving biohazard exposure of a clinician (Complaint # [redacted] dated [redacted])."

Furthermore, Medline Industries was cited for other violations, including failing to maintain schedules for adjusting, cleaning, and performing other equipment maintenance to ensure compliance with manufacturing specifications. It was also cited for failing to ensure its device inputs met its design outputs.

FDA asked Medline Industries to respond to its warning letter within 15 business days and noted that since the December 2025 inspection, the agency has updated its Quality System (QS) regulation to the Quality System Management Regulation (QMSR) to harmonize with international regulatory standards. FDA told the company to ensure its response complies with QSMR.

Medline Industries

Clinical investigator

Ehsan Sadri, an ophthalmologist and researcher based in Newport Beach, CA, was issued a warning letter from FDA for failing to adhere to clinical trial protocols. FDA investigators said he failed to ensure that all subjects in his clinical trial met eligibility criteria before they were enrolled. More specifically, they noted that at least one subject's Central corneal endothelial cells (CEC) density measurement was not completed before enrollment, which was one of the enrollment criteria, and another enrolled subject had Intraocular pressure (IOP) that was outside the criteria.

Sadri responded to FDA's Form 483 to explain the discrepancies, including delayed activation of the clinical trial site and shortening of the enrollment period, and said he would update the standard operating procedures. However, FDA said the responses were insufficient.

"While we acknowledge your response that an abrupt shortening of the enrollment period led to challenges and mistakes, your response is inadequate because, regardless of the length of the enrollment period, you are still responsible for ensuring that subjects meet protocol-specified eligibility criteria before you enroll them into the study," said FDA. "Further, while we acknowledge the corrective and preventive actions that your site has taken or plans to take, your written response is inadequate because it does not provide sufficient details about how you, as a clinical investigator, will ensure adequate oversight of the study procedures (for example, adherence to eligibility requirements).

"In addition, your response is inadequate because you did not provide sufficient details about proposed changes to policies and procedures being implemented at your site to prevent similar violations in the future. Without this information, we are unable to determine whether your corrective action plan is adequate to prevent similar violations in the future," the agency added. "We emphasize that as the clinical investigator, it is your responsibility to ensure that studies are conducted in accordance with the investigational plan, both to protect the rights, safety, and welfare of subjects and to ensure the integrity of study data."

FDA noted that two of the nine randomized subjects who received the investigational product were not eligible under the enrollment criteria. The agency said such discrepancies raise concerns about the safety of the trial subjects and the reliability of the trial data.

Ehsan Sadri