Glycine
| Evidence Level: L5 | Predicted Indications: 2 |
Table of Contents
Glycine: A Predicted Candidate for Nasal Cavity Disease
One-Sentence Summary
Glycine (DrugBank DB00145) is a naturally occurring amino acid and inhibitory neurotransmitter; no original indication is recorded in this evidence pack, and the drug does not currently hold a UK marketing authorisation. The TxGNN model predicts a possible signal for Nasal Cavity Disease, but this is currently supported only by 1 clinical trial and 2 publications, none of which actually studied glycine for this indication.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not documented in this evidence pack |
| Predicted New Indication | Nasal Cavity Disease |
| TxGNN Prediction Score | 99.85% |
| Evidence Level | L5 (model prediction only) |
| UK Market Status | Not Marketed |
| Number of Marketing Authorisations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data for glycine is not available in this evidence pack. Based on general pharmacological knowledge referenced in the model’s rationale, glycine acts as an inhibitory neurotransmitter, and its receptor (GlyR) is also expressed on mucosal epithelium and immune cells — theoretically giving it anti-inflammatory and mucosal-barrier-protective potential.
However, this mechanistic link is purely inferential. None of the clinical trials or literature retrieved for this candidate actually investigated glycine’s use in nasal cavity disease; the connection rests on receptor biology reasoning alone, with no direct supporting evidence identified to date.
Because no original indication or approved use is recorded for glycine in this pack, the usual comparison between an established indication and the predicted new one cannot be made here.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrolment | Key Findings |
|---|---|---|---|---|
| NCT01806675 | Phase 1/2 | Completed | 25 | PET/CT and PET/MRI imaging study of the radiopharmaceutical ¹⁸F-FPPRGD2 as an angiogenesis biomarker in glioblastoma, gynaecological cancers and renal cell carcinoma. Glycine is not the study intervention and the trial does not address nasal cavity disease — likely surfaced by keyword co-occurrence rather than genuine relevance. |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 7771054 | 1995 | Basic/Histochemistry (animal) | Veterinary Pathology | Lectin histochemistry of bovine nasal mucosa in normal vs. herpesvirus-infected cattle; does not evaluate glycine. |
| 29607903 | 2018 | Basic/Materials science | Chemical & Pharmaceutical Bulletin | Investigates oligoarginine-conjugated polymers as a nasal mucosal vaccine adjuvant; does not evaluate glycine. |
Both publications are tier-3, mechanistically tangential, and neither directly studies glycine in the context of nasal cavity disease.
UK Market Information
Glycine currently has no recorded UK marketing authorisations in this dataset (market status: Not Marketed; total licences: 0).
Safety Considerations
Please refer to the SmPC and BNF for safety information. Report suspected adverse reactions via the Yellow Card Scheme.
(No key warnings, contraindications, or drug interaction data were retrievable for this candidate; the underlying label/warning data is flagged as a blocking data gap — see Next Steps.)
Conclusion and Next Steps
Decision: Hold
Rationale: The TxGNN score is high, but the supporting evidence base is effectively absent — the single clinical trial does not use glycine as an intervention, and both literature items are tangential animal/materials-science studies unrelated to glycine in nasal cavity disease. This corresponds to Evidence Level L5 (model prediction only, no substantive supporting studies).
To proceed, the following is needed:
- TFDA/MHRA product label warnings and contraindications (currently a blocking data gap — required before any safety pre-screen)
- Confirmed mechanism of action data from DrugBank or equivalent source
- Preclinical or clinical studies directly evaluating glycine in nasal cavity disease (current evidence is indirect/keyword-matched only)
- Clarification of glycine’s original approved indication(s), if any, to support a mechanistic rationale for repurposing
- Confirmation of UK regulatory/marketing status before any further development consideration
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.