FOI release
Seizures, Laboratory Testing, and Adverse Incident Reports (Retatrutide / Unapproved Peptides)
This request was refused in part, so we didn't provide some of the information the requester asked for. This may include information where we can neither confirm nor deny that we hold it.
Case reference FOI2026/01010
Received 8 September 2026
Published 15 October 2026
Request
Under the Freedom of Information Act 2000, I hereby request the disclosure of information held by the Medicines and Healthcare products Regulatory Agency (MHRA) regarding the illegal importation, border detention, chemical testing, and reported adverse health events associated with the investigational peptide "Retatrutide" (also known as LY3437943). Please provide responsive records covering the period from 1 January 2024 to the date of processing, specifically addressing the following three areas: 1. BORDER DETENTIONS & ENFORCEMENT SEIZURES (Criminal Enforcement Unit): a. The total number of seizures, detentions, or postal intercepts executed by or referred to the MHRA Criminal Enforcement Unit (CEU) involving products labelled, marketed, or suspected to be "Retatrutide" or novel triple-agonist (GLP-1/GIP/glucagon) peptides. b. For each recorded seizure/intercept (in an anonymised table or line listing): - Date of seizure/detention. - Total quantity seized (e.g., number of vials, ampoules, or weight of bulk powder). - Declared country of export/origin (where known). - Transit channel (e.g., air cargo, international mail hub, or courier consignment). - Deceptive customs descriptions utilised (e.g., "cosmetics," "research chemicals," "glassware"). 2. LABORATORY TESTING & DEFECT PROFILING: a. Summaries or final analytical certificates of any laboratory analysis, potency testing, or purity screening conducted on seized or test-purchased vials labelled as "Retatrutide." b. Specifically, records indicating whether tested samples contained: - The declared active pharmaceutical ingredient (retatrutide) vs. alternate substances (e.g., semaglutide, tirzepatide, or inactive filler). - Dosage variances (sub-potent or super-potent concentrations). - Microbiological contamination, endotoxins, heavy metals, or unlisted preservatives/bacteriostatic agents. 3. YELLOW CARD & ADVERSE REACTION REPORTS: a. A de-identified line listing of all suspected Adverse Drug Reaction (ADR) reports received via the Yellow Card scheme where the suspect drug was recorded as "Retatrutide," "LY3437943," or an unspecified/unlicensed weight-loss peptide. b. For each report, please provide: - Date of report. - Patient age group and sex (where recorded). - Reported adverse reaction terms (MedDRA preferred terms, e.g., tachycardia, pancreatitis, severe vomiting, injection site abscess). - Reported outcome (e.g., resolved, hospitalisation, life-threatening). - Product source or formulation noted (e.g., "purchased online," "reconstituted powder," "aesthetic clinic"). HANDLING EXEMPTIONS & SECTION 12 COST LIMIT: - Section 40 (Personal Data): This request specifically excludes direct personally identifiable information (PII) of patients, clinicians, and agency staff below Senior Civil Service level. All patient-identifying details and names of targets in active investigations may be redacted without consultation. - Sections 30 & 31 (Law Enforcement & Investigations): If specific ongoing investigations cannot be disclosed, please segregate and release all aggregate statistics, finalized test certificates, closed enforcement summaries, and Yellow Card pharmacovigilance data, which carry a strong public interest in protecting public health from counterfeit injectables. - Section 12 (Cost Limit): If you estimate that retrieving any specific sub-part of this request will exceed the statutory £450 / 18-hour limit, please contact me immediately and prioritize sections 1(a), 2(a), and 3(a) before refusing the request in its entirety. Pursuant to Section 10(1) of the Act, I look forward to receiving your response within 20 working days.
Response
See attached
Documents
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