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FDA Warning Letters to 7 Peptide Companies (April 2026) — VialBase News

Last updated · April 7, 2026

FDA Warning Letters to 7 Peptide Companies (April 2026)

On April 7, 2026, the FDA published warning letters to seven companies involved in the sale of peptides and related products. The letters, dated March 31, 2026, targeted both domestic and international sellers and introduced a significant new enforcement theory: that bacteriostatic water sold alongside peptides constitutes a drug.

Source Documents

Companies Targeted

1. Prime Sciences

  • Location: United States
  • Products cited: Various peptide products including BPC-157 and TB-500
  • Key violations: Selling unapproved new drugs; marketing peptides with therapeutic claims
  • Notable: Website included dosing instructions and therapeutic use guidance, undermining the “research only” defense

2. Lovega

  • Products cited: Peptide products marketed for human use
  • Key violations: Unapproved new drug distribution; misbranding
  • Notable: Marketing materials made explicit health claims

3. Gram Peptides

  • Products cited: Multiple peptide products
  • Key violations: Selling unapproved new drugs; therapeutic marketing claims
  • Notable: One of the more prominent vendors to receive a warning letter

4. FormPour

  • Products cited: Peptide products and reconstitution supplies
  • Key violations: Unapproved new drug distribution
  • Notable: Selling reconstitution kits that implied human use

5. Guangzhou Huli Technology

  • Location: China
  • Products cited: Bulk peptide products sold to US customers
  • Key violations: Exporting unapproved drugs into the United States
  • Notable: Rare example of FDA issuing warning letter to a Chinese supplier directly; signals intent to target the upstream supply chain

6. Mile High Compounds LLC

  • Location: United States
  • Products cited: Compounded peptide products
  • Key violations: Compounding without proper 503A or 503B registration; unapproved new drugs
  • Notable: Operating as a compounder without meeting regulatory requirements

7. PekCura Labs

  • Products cited: Peptide products including growth hormone secretagogues
  • Key violations: Unapproved new drug distribution; therapeutic marketing
  • Notable: Marketing materials included clinical references and dosing protocols

The Bacteriostatic Water Precedent

The most significant legal development in these warning letters was the FDA’s classification of bacteriostatic water sold alongside peptides as a drug.

The Argument

  • Bacteriostatic water (sterile water with 0.9% benzyl alcohol as a preservative) is itself a regulated product when sold for injection
  • When sold alongside lyophilized peptides — especially with reconstitution instructions — the FDA argued it constitutes part of a drug product
  • This is because the bac water is clearly intended for use in preparing an injectable drug, making it an unapproved drug component
  • Even vendors who avoided making direct therapeutic claims about the peptides were caught by this theory if they sold bac water as a companion product

Why This Matters

This is a significant expansion of FDA enforcement theory:

  1. Closes a loophole: Vendors who carefully avoided therapeutic claims about peptides could still be targeted for selling the reconstitution supplies
  2. Broader applicability: This theory could apply to any vendor selling syringes, bac water, or mixing supplies alongside research peptides
  3. Precedent setting: If upheld, this interpretation gives the FDA a new tool to target the grey-market peptide supply chain
  4. Supply chain impact: Bac water vendors who don’t sell peptides may also need to evaluate their customer base and marketing

Timing and Context

These warning letters are notable for their timing:

  • Issued after the Kennedy reclassification announcement in February 2026
  • Signals that FDA enforcement staff continued operating under existing policy despite the political announcement
  • Demonstrates the gap between political announcements and actual regulatory implementation
  • Reinforces that the Category 2 designations remain in effect until formally changed

Implications

For Vendors

  • Grey-market peptide vendors face escalating legal risk
  • The bac water theory means even “clean” vendors who avoided therapeutic claims are exposed
  • Expect more warning letters and potential escalation to injunctions or criminal referrals

For Consumers

  • Access to grey-market peptides continues to narrow
  • Quality and reliability of remaining vendors is uncertain
  • The gap between the Kennedy announcement and implementation leaves consumers in limbo

For the Industry

  • The FDA is clearly not waiting for the Kennedy reclassification to take effect
  • Enforcement and reclassification are proceeding on parallel tracks
  • Companies should not assume the reclassification will protect them from current enforcement actions
  • FDA-Category-2-Designations-2023-2024 — original restrictions being enforced
  • FDA-Reclassification-Announcement-Feb-2026 — pending reversal that hasn’t stopped enforcement
  • Peptide-Sciences-Shutdown-March-2026 — vendor shutdown one month before these letters
  • Science-Bio-Shutdown-January-2026 — earlier vendor closure
  • FDA-503A-Category-System — the regulatory framework
Source: Regulatory →