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.
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.
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.