A name can cross a border while its approval stays put.
Approved where, and for what? Those are the words I add when an approval claim arrives without much explanation. A medicine’s story in another country can be interesting without becoming an answer for a U.S. reader.
Authorisation
Thymosin alpha-1 is a peptide involved in the immune system’s signals. Its man-made version, with the same amino-acid sequence, is called thymalfasin. FDA’s review describes its foreign authorisations and lack of U.S. approval. In Italy, its authorised use is an add-on to flu vaccination for people with weakened immune systems.
That’s more specific than approved overseas. The review also describes injection-site soreness in studies and concerns about ingredient quality and immune reactions. The body may respond to an injected peptide as something foreign. A different preparation needs its own safety explanation.
Semax offers another example. FDA’s 2026 review describes Russian registration as nasal drops. It isn’t FDA-approved, and FDA found too little information to establish its safety in people. I keep the country, form and safety limits together.
A foreign authorisation leaves the U.S. access question open.
Compounding
Compounding means preparing a medicine under a separate set of rules. In the U.S., 503A generally concerns a preparation for an individual with a prescription; 503B concerns registered outsourcing facilities. These are sections of law. FDA’s compounding explanation also makes clear that compounded drugs aren’t FDA-approved.
A prescription doesn’t make every starting ingredient eligible. FDA’s bulk-ingredient rules set conditions for what can be used. Bulk ingredient just means the starting drug substance. A clinician’s assessment and those ingredient rules both matter.
On FDA’s page current as of April 22, 2026, BPC-157, epitalon, semax, selank and thymosin alpha-1 appear among nominations that were withdrawn. Withdrawal isn’t clearance, Category 1 placement or approval for compounding. FDA keeps its safety concerns beside the entries and gives no individual move dates.
A research label adds another word to unpack.
Research
Research use only doesn’t turn a substance into an approved medicine. FDA’s warning about unapproved peptide drugs explains that research wording doesn’t excuse marketing them for human use. The label can’t supply the missing approval or safety evidence.
A 2021 review describes selank as poorly studied; it has no FDA approval. Neither do epitalon or BPC-157, whose human safety evidence remains inadequate. A name travelling between countries doesn’t resolve those gaps.
For a personal U.S. medical question, a licensed clinician can assess appropriate options, in person or through suitable telehealth, including approved medicines where they exist. I explain the words around that conversation. Athletes also have a separate set of sport rules to consider.
Sport has its own rules to add to the conversation.