Read the primary source rather than the write-up and the two do not agree, so here is what is actually in it.
Freezing is the one to avoid, and freeze-thaw more so. Ice-crystal formation and the concentration changes at the phase boundary drive aggregation, and aggregated peptide does not recover on thawing. A vial that has been frozen and thawed is not rescued by returning it to the fridge.
Where I think it is weakest: the completion rate deserves as much attention as the headline, because a large effect among those who finished is a different claim from a large effect among those enrolled.
What I actually want to know is what a temperature excursion actually does, and what distinguishes an unopened vial from one already in use. If the honest answer is that nobody knows, that is a useful answer and I would rather have it.
Figures above are from the primary publication rather than the press summary. If a number here disagrees with one you have, post yours and we will work out which of us is reading a secondary source.
PeptideSynthNJ said:Freezing is the one to avoid, and freeze-thaw more so.
Storage question about storage and cold: my pen was left out of the fridge for 6 hours. Is it still good?
Per the manufacturer, both Ozempic and Wegovy pens can be stored at room temp (up to 86°F) for up to 28 days after first use. So yes, it should be fine as long as it wasn't exposed to extreme heat.
PeptideSynthNJ said:Freezing is the one to avoid, and freeze-thaw more so.
Pushing back on PeptideSynthNJ here. The distinction that matters is unopened versus in use. Unopened vials are stable refrigerated for their labelled shelf life and tolerate a limited excursion to room temperature. Once reconstituted, the clock is much shorter and is set by the preservative rather than by the peptide — bacteriostatic water's benzyl alcohol is what buys you multiple draws over weeks. Sterile water has no preservative and turns a multi-dose vial into a single-use one.
Happy to go further on any of that.
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Shop Reference StandardsDr.NateNeph said:The distinction that matters is unopened versus in use.
Cold chain shipping for storage and cold: my last order arrived with the cold pack completely melted and the vial at room temperature. I contacted the vendor and they reshipped with better insulation.
What to look for in shipping: styrofoam inner container with ice packs. If your peptide arrives warm, contact the vendor immediately. Don't assume it's still good.
LabKate said:Storage question about storage and cold: my pen was left out of the fridge for 6 hours.
Adding a me-too, because a thread of one person's experience is not much use. The detail I would add is minor and it is already implied above.