NucLexNuclear Medicine Lexicon and Theranostics Ontology
Stage W0: private living prototype12 of 30 manuscripts drafted, 0 reviewed; 50 lexicon entries in draftWhat each later stage would need to show

NucLex for innovators

Radiopharmaceutical identity

A radionuclide, a ligand, a conjugate, a formulation, and a vial drawn up for one patient are five different things that share a name.

MonographBriefNX-M14Proposed length 2,500 to 5,000 words

Writing brief. This monograph has been assigned but the manuscript is not yet written or approved. What follows is the commissioning brief: its question, outline, evidence instructions, and review requirements.

Central question

What object must be described consistently?

Reader promise

The reader will be able to take any name used for a radiopharmaceutical and say which level of identity it refers to, what would make two such names denote the same thing, and which external authority anchors that level.

Required development

  1. Distinguish five levels. Define radionuclide, ligand (small molecule, peptide, or antibody), conjugate (ligand plus chelator or linker), formulation (dosage form, excipients, specific activity), and administered product (activity given, with lot, time, and route). Show with a synthetic example that one ligand with two radionuclides is different at one level and the same at another.
  2. Explain identity and context. Two names denote the same object only relative to a level. Explain why "equivalent" in a mapping must state the level at which it holds; connect to Context.
  3. Research the source authorities. For each level, identify the registry or terminology the discussion named (PubChem, FDA Global Substance Registration System, RxNorm, UniProt for protein targets) and state what kind of identifier each issues and for what kind of object. Print no external identifier unless verified against the authority's current record.
  4. Separate regulatory status from chemical identity. An approved product and an investigational agent may share a conjugate; approval attaches to the formulation and sponsor, not the molecule. Treat any regulatory statement as a claim needing its own source.
  5. Show the consequence for records. Connect to the worked example in SNOMED CT and the NucLex niche, where substance, product, and procedure sit in different hierarchies, and to Molecular targeting for the ligand's target.

Evidence and review

Evidence to obtain: FDA GSRS documentation on substance definition and UNII assignment; PubChem documentation distinguishing compound, substance, and bioassay records; RxNorm documentation on ingredient, clinical drug, and branded drug term types; a pharmacopoeial or regulatory definition of radiopharmaceutical; peer-reviewed radiochemistry sources on chelator and linker chemistry. Every identifier printed must be verified at source and dated.

Review concern: the manuscript must not assert that two named agents are equivalent, that any product is approved for any use, or that any identifier corresponds to any agent, without a verified source.

Radiopharmaceutical, Radionuclide, Ligand, Peptide, Identifier, Context, Theranostics, SNOMED CT and the NucLex niche, Molecular targeting, Biodistribution and pharmacokinetics.

Review requirements

Source check of every identifier and regulatory statement against the issuing authority. Domain review by a radiochemist or radiopharmacist and a regulatory affairs reviewer. Editorial check that each use of "radiopharmaceutical" names its level.

Review gate for this monograph

Verify identifiers, regulatory claims, and equivalence.

The assignment exists. The manuscript has not been written or approved.