Peptide Sciences vs Life Link Research — Historical Comparison (Post-Shutdown)

Peptide Sciences voluntarily closed on March 6, 2026. Before closure, they were the largest US research peptide vendor at an estimated $7.4 million in monthly revenue. This page compares Peptide Sciences (historical) against Life Link Research (current operating vendor) so researchers searching for a Peptide Sciences replacement can evaluate the differences.

For the full backstory on the closure, see What Happened to Peptide Sciences.

Historical Comparison

Factor	Peptide Sciences (closed March 2026)	Life Link Research
Status	❌ Permanently closed	✅ Operating
COA standard	Third-party referenced (some panels) — quality issues flagged before closure	Six-panel third-party independent on every batch
GLP-1 range	Comprehensive when operating	Comprehensive — semaglutide (10mg, 15mg), tirzepatide, retatrutide, CagriSema
Retatrutide	Stocked — but flagged as potentially counterfeit by third-party testing before closure	Stocked with independent mass spectrometry verification
Order fulfillment	❌ Pending orders not fulfilled after closure	2-4 business days US domestic
Catalog scope	Peptides only	Peptides only

What Researchers Lost When Peptide Sciences Closed

Peptide Sciences had been the de facto category leader for several years. Their core advantages: established track record, GLP-1 range, consistent US shipping. The third-party COA documentation, while reasonable, was not consistently six-panel — and in late 2025, independent third-party testing flagged quality issues that ultimately contributed to the closure decision. CJC-1295 from Peptide Sciences was rated grade E by independent testing platforms. Retatrutide samples were flagged as potentially counterfeit by independent mass spectrometry. These findings, combined with the broader regulatory environment, drove the March 2026 closure decision.

What Life Link Research Offers as a Replacement

Life Link Research is the most direct Peptide Sciences replacement for researchers who valued the GLP-1 range and US-based sourcing — with one critical upgrade: every batch ships with six-panel third-party independent COA documentation. This is specifically the verification standard that would have caught the retatrutide and CJC-1295 quality issues at Peptide Sciences before they reached customers. The six panels: HPLC purity (≥98%), mass spectrometry, LAL endotoxin, sterility, moisture, amino acid composition. COAs available before purchase.

What to Do If You Have Pending Peptide Sciences Orders

Peptide Sciences has not communicated about refunds for unfulfilled orders. For credit card payments, initiate a chargeback with your card issuer immediately (typically successful if filed within 60-120 days). For cryptocurrency payments, recovery is very difficult. For ACH/bank transfer, contact your bank to dispute.

FAQs

When did Peptide Sciences shut down?

March 6, 2026. Voluntary closure following converging FDA enforcement pressure, ITC tirzepatide import restrictions, third-party testing quality findings, and the SAFE Drugs Act introduction.

Is Peptide Sciences coming back?

No. The closure is permanent. Any site still appearing to be Peptide Sciences accepting orders after March 6, 2026 should be treated with extreme caution.

What is the best Peptide Sciences alternative?

For researchers who valued Peptide Sciences’ GLP-1 range and US-based sourcing, Life Link Research is the most direct replacement with the additional upgrade of six-panel third-party independent COA verification.

Were Peptide Sciences’ GLP-1 products safe?

For most of their catalog, products likely matched what was labeled. The exceptions: their CJC-1295 was rated grade E by independent testing, and retatrutide samples were flagged as potentially counterfeit by independent mass spectrometry.

View Life Link Research products →

For research purposes only. Not for human use. Historical claims about Peptide Sciences are based on publicly available information including third-party testing platform data.