FDA Issues 55+ Warning Letters to GLP-1 Compounders

Summary

On September 16, 2025, the FDA published over 55 warning letters targeting online sellers of compounded GLP-1 medications (Semaglutide, Tirzepatide). This was the largest single-day enforcement action in the FDA’s history against the compounding industry, and it marked the beginning of a sustained crackdown that continued into 2026.

Background

After the FDA resolved the Semaglutide shortage in February 2025 and the Tirzepatide shortage in December 2024, compounding pharmacies lost their legal basis for producing these drugs under the shortage exemption. Despite this, many telehealth platforms and online sellers continued marketing compounded GLP-1 products directly to consumers.

What triggered the letters:

• False equivalence claims: Telehealth companies implied compounded products were identical to FDA-approved Ozempic, Wegovy, or Mounjaro
• Brand name misuse: Sellers marketed products under their own trademarks without clarifying the compounder source
• Missing safety disclosures: Products lacked required warnings about compounded drug risks
• Continued post-shortage sales: Sellers kept offering compounded GLP-1s after shortage exemptions expired

Scale of enforcement:

• 55+ warning letters issued September 16, 2025
• A second batch of letters followed in October 2025
• FDA Commissioner Marty Makary announced a broader clampdown on illegal GLP-1 compounders in October 2025
• Over the following six months, the FDA sent thousands of letters to pharmaceutical and telehealth firms — more than were sent over the entire preceding decade

Impact

• Telehealth platforms hit hardest: Companies like Hims & Hers saw stock price drops on the news
• Signal to broader peptide market: While focused on GLP-1s, the enforcement intensity sent a clear message to all compounders
• Preceded physical enforcement: This wave of letters preceded the Amino Asylum raid and DOJ criminal prosecutions
• Manufacturer coordination: The timing aligned with Eli Lilly and Novo Nordisk lawsuits against compounders, suggesting coordinated regulatory and private enforcement

What This Means for Researchers

• The FDA’s willingness to issue warning letters at this scale demonstrates that the agency has the infrastructure and political will for mass enforcement
• “Research use only” disclaimers on peptide products are under increasing scrutiny — the FDA applies the Intended Use Doctrine based on marketing context, not just labels
• Vendors operating in grey areas should expect escalation: warning letters are typically the first step before injunctions, seizures, or criminal referrals

Related Compounds

• Semaglutide
• Tirzepatide

Sources

• FDA — Compounding Inspections, Recalls, and Other Actions
• Becker’s Hospital Review — FDA Warns 30 Telehealth Firms
• Seeking Alpha — Hims & Hers Down as FDA Targets Compounders
• The Pharma Letter — Further FDA Warning to Telehealth Companies
• FDA — Concerns with Unapproved GLP-1 Drugs