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October 28, 2026CompoundingHHS lets 503A pharmacies compound six peptides under an interim enforcement discretion policyOctober 28, 2026Trial resultRetatrutide beats Ozempic on blood sugar and weight in head-to-head TRANSCEND-T2D-2 trialOctober 23, 2026FDA approvalFDA extends once-weekly insulin icodec (Awiqli) to children 10 and older with type 2 diabetesOctober 21, 2026CompoundingCitizen petition asks FDA not to allow compounding of seven peptides reviewed by its advisory committeeOctober 1, 2026Trial resultSurvodutide SYNCHRONIZE-2 phase 3 results in obesity with type 2 diabetes published in NEJMSeptember 30, 2026Trial resultEloraTZP (eloralintide plus tirzepatide) phase 2 results presented at EASD 2026September 30, 2026Trial resultOrforglipron ACHIEVE-4 cardiovascular safety trial published in The LancetSeptember 29, 2026Trial resultFull TRIUMPH-2 retatrutide results published in The LancetSeptember 24, 2026FDA approvalFDA approves insulin efsitora alfa (Onswik), a once-weekly basal insulin for type 2 diabetesSeptember 21, 2026WADAWADA publishes 2027 Prohibited List, naming peptides as examples of non-approved substances

October 28, 2026CompoundingHHS lets 503A pharmacies compound six peptides under an interim enforcement discretion policyOctober 28, 2026Trial resultRetatrutide beats Ozempic on blood sugar and weight in head-to-head TRANSCEND-T2D-2 trialOctober 23, 2026FDA approvalFDA extends once-weekly insulin icodec (Awiqli) to children 10 and older with type 2 diabetesOctober 21, 2026CompoundingCitizen petition asks FDA not to allow compounding of seven peptides reviewed by its advisory committeeOctober 1, 2026Trial resultSurvodutide SYNCHRONIZE-2 phase 3 results in obesity with type 2 diabetes published in NEJMSeptember 30, 2026Trial resultEloraTZP (eloralintide plus tirzepatide) phase 2 results presented at EASD 2026September 30, 2026Trial resultOrforglipron ACHIEVE-4 cardiovascular safety trial published in The LancetSeptember 29, 2026Trial resultFull TRIUMPH-2 retatrutide results published in The LancetSeptember 24, 2026FDA approvalFDA approves insulin efsitora alfa (Onswik), a once-weekly basal insulin for type 2 diabetesSeptember 21, 2026WADAWADA publishes 2027 Prohibited List, naming peptides as examples of non-approved substances

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Making peptides · Part 9: Sterility and endotoxin

Endotoxin, the invisible contaminant

Lesson 4.9.2 · 6 min read · Advanced plan

What you'll learn

Endotoxins are lipopolysaccharides from gram-negative bacteria, released when the cells die.
Sterilizing filters and moist heat don't remove endotoxin, so a sterile product can still contain it.
Endotoxin is hard to destroy, so manufacturers must keep it out from the start.
Batches labeled pyrogen-free must be tested; the LAL test is the main method, and the older rabbit test still exists.

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