I froze a spare vial thinking I was being careful and later found out that is the one thing you are not supposed to do.
Practical: unopened, refrigerated at 2 to 8°C; in use, refrigerated and used within the preservative-limited window; never frozen; and a visual check every time — a haze that does not settle is a reason to stop, not to wonder.
What I am after is what a temperature excursion actually does, and what distinguishes an unopened vial from one already in use.
Tell me what I have not thought of.
Taking the question as asked, rather than the general version of it. They are two different exemptions from the same federal requirements and they buy different things. A 503A pharmacy is regulated primarily by the state board, needs a patient-specific prescription, is exempt from CGMP, and may use a bulk substance that has a USP monograph, is a component of an approved drug, or appears on the 503A bulks list — three independent doorways. A 503B outsourcing facility registers with the FDA, is inspected on a risk basis, must comply with CGMP, may compound for office stock without a patient-specific prescription, and has one doorway to a permitted bulk substance: the 503B bulks list, or the drug shortage list.
FDA_TrackerJim said:They are two different exemptions from the same federal requirements and they buy different things.
FDA_TrackerJim has the substance of this right. The condition it depends on is worth stating. 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.
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View ResultsMikeFit_NJ said:I froze a spare vial thinking I was being careful and later found out that is the one thing you are not supposed to do.
Agreed, and the enforcement dates were staggered by category — 503A first, 503B a few weeks later — because outsourcing facilities have manufactured inventory and clinic contracts to unwind while a 503A makes to order.
I would rather be corrected than agreed with, if it comes to it.
From the other side of the consultation, briefly.
Storage best practices for compounded storage and cold:
- Unreconstituted lyophilized powder: refrigerate (36-46°F), good for 12+ months
- Reconstituted vials: refrigerate, use within 28 days
- Pre-filled pens: refrigerate until first use, then room temp OK for 28 days
- Never freeze reconstituted peptides — ice crystals damage the protein
- Protect from light — store in original box or wrap in foil
When in doubt, refrigerate. Temperature abuse is the #1 cause of reduced potency in compounded peptides.