Methionine
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
Methionine: From Parenteral Nutrition Amino Acid to Acne
One-Sentence Summary
Methionine is an essential amino acid used as a component of parenteral nutrition (amino acid infusion) products in Singapore. The TxGNN model predicts it may be effective for acne, with a very high computational score but 0 clinical trials and only 2 publications, neither of which tests methionine as a treatment.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not stated in the licence data (marketed as a component of amino acid and parenteral nutrition products) |
| Predicted New Indication | Acne (disease) |
| TxGNN Prediction Score | 99.99% |
| Evidence Level | L5 |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 19 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, methionine is a sulfur-containing essential amino acid and part of multi-component amino acid infusions. It is a precursor in homocysteine and cysteine metabolism, and its role in nutrition support is established. Mechanistically, it may be relevant to acne only through indirect metabolic pathways.
The data compiled for this report do not support a direct link. The only acne-related paper reports raised plasma homocysteine in patients taking isotretinoin. That is a side effect of another drug on methionine/homocysteine metabolism, not a therapeutic effect of methionine. The second paper describes a neonatal genetic disorder (MTHFR mutation) in which acne was only one of several skin findings. The very high TxGNN score is therefore a computational prediction without clinical support.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 11277950 | 2001 | Cohort | International Journal of Dermatology | Plasma homocysteine was elevated in patients taking isotretinoin for cystic acne. This concerns a drug side effect, not a benefit of methionine. |
| 39357918 | 2024 | Case report | BMJ Case Reports | A neonate with a novel MTHFR mutation had encephalopathy, hair loss, marfanoid features and neonatal acne. Not relevant to acne treatment. |
Singapore Market Information
All 19 licences are valid single-ingredient registrations. No approved indication text is recorded for them. Five main authorisations are listed.
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN16337P | AMINOVEN SOLUTION FOR INFUSION 15% | Infusion, solution | Not recorded |
| SIN11682P | AMINOVEN SOLUTION FOR INFUSION 5% | Injection | Not recorded |
| SIN11829P | AMINOVEN SOLUTION FOR INFUSION 10% | Injection | Not recorded |
| SIN06299P | NEPHROSTERIL FOR INTRAVENOUS INFUSION | Injection | Not recorded |
| SIN08352P | AMINOPLASMAL-15% INFUSION | Injection | Not recorded |
Safety Considerations
- Disease associations flagged in the knowledge graph (not label text): The TxGNN knowledge graph links methionine to contraindications in several disease groups. These include kidney disease (chronic kidney disease, end-stage renal failure, nephrolithiasis, nephrocalcinosis), cardiovascular disease (hypertension, heart disease, ventricular fibrillation, digitalis poisoning), metabolic disorders (diabetes mellitus, diabetic ketoacidosis, hyperlipidaemia, phenylketonuria and other phenylalanine metabolism disorders, phosphorus metabolism disease), and calcium-related conditions (hypercalcaemia, sarcoidosis). These are knowledge-graph edges and need confirmation against the product labels.
- Drug Interactions (5 recorded):
- Moderate: activated charcoal
- Minor: ephedrine, pseudoephedrine, mexiletine, flecainide
Please refer to the package insert for full safety information. Warnings and contraindications from the label were not available.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction rests on a computational score alone. There are no clinical trials, and the two papers do not test methionine for acne. The acne-related paper points to a possible harm signal (homocysteine) rather than benefit.
To proceed, the following is needed:
- Package insert warnings and contraindications from the HSA, since safety screening cannot proceed without them
- Mechanism of action data for methionine
- Preclinical or clinical evidence that methionine has a therapeutic effect in acne
- Clarification of the direction of effect (whether methionine or homocysteine changes help or harm)
- Assessment of route compatibility, since the registered forms are all parenteral and acne would likely need a different route
Other predicted indications (for reference): Diabetic cataract is the most plausible of the ten predicted indications. It has indirect support from homocysteine and methionine sulfoxide reductase B1 research (evidence level L4, research question stage). The remaining predicted indications, including severe nonproliferative diabetic retinopathy and several cataract types, are held at L4–L5 without direct evidence.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.