Diclofenac
| Evidence Level: L5 | Predicted Indications: 10 |
Table of Contents
- Diclofenac
- Diclofenac: From Osteoarthritis and Rheumatoid Arthritis to Juvenile Idiopathic Arthritis
Diclofenac: From Osteoarthritis and Rheumatoid Arthritis to Juvenile Idiopathic Arthritis
One-Sentence Summary
Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) originally used for arthritic conditions (rheumatoid arthritis, osteoarthritis, ankylosing spondylitis) and for skin conditions such as actinic keratosis. The highest-ranked prediction by the TxGNN model, hypotrichosis simplex of the scalp, has no supporting studies. The best-supported prediction in the top 10 is Juvenile Idiopathic Arthritis, with 0 registered clinical trials and 14 publications (mostly small, older studies).
This report presents the top-ranked prediction in the Quick Overview, then focuses the evidence discussion on juvenile idiopathic arthritis, the only candidate in the top 10 with supporting literature.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not stated in the Singapore licence records. The drug knowledge graph lists rheumatoid arthritis, osteoarthritis, ankylosing spondylitis and actinic keratosis, among others. |
| Predicted New Indication (rank 1) | Hypotrichosis simplex of the scalp |
| TxGNN Prediction Score (rank 1) | 99.69% |
| Evidence Level (rank 1) | L5 |
| Best-Supported Candidate | Juvenile idiopathic arthritis (score 99.25%, Evidence Level L3) |
| Singapore Market Status | ✓ Marketed |
| Number of Registrations | 20 |
| Recommended Decision | Rank 1: Hold. Juvenile idiopathic arthritis: Proceed with Guardrails |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not available in the data compiled for this report. Diclofenac is, however, a well-known NSAID that inhibits COX-1 and COX-2, which reduces prostaglandin-mediated inflammation, pain and stiffness. This is consistent with its established use in rheumatoid arthritis and osteoarthritis.
Juvenile idiopathic arthritis (JIA) is mechanistically a close relative of the original arthritis indications. The supplied literature includes small clinical studies of diclofenac in juvenile arthritis and reviews of NSAID use in paediatric rheumatic disease. These support symptomatic use (pain, stiffness, inflammation), not disease modification.
The rank 1 prediction (hypotrichosis simplex of the scalp) has no clear link. It is a genetic hair-follicle disorder. Prostaglandin modulation could theoretically affect the hair cycle, but the direction of effect is uncertain: PGD2 inhibits hair growth, while PGE2 and PGF2α promote it. The high score appears to be a graph-based prediction only.
Most other top-10 predictions are rare skeletal, hair or immune disorders (e.g., acromesomelic dysplasia, pseudoachondroplasia, brachyolmia, WHIM syndrome, diffuse alopecia areata). They have no supporting evidence and no plausible mechanistic link beyond possible symptomatic pain relief. They are likely driven by graph proximity to musculoskeletal disease nodes.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
For juvenile idiopathic arthritis (listed by priority: clinical studies first, then reviews):
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 3052965 | 1988 | Crossover trial | Clin Exp Rheumatol | Single-blind 12-week crossover of naproxen, tolmetin and diclofenac (2 mg/kg/day) in 28 children with seronegative juvenile chronic arthritis |
| 6361986 | 1983 | Clinical study | Scand J Rheumatol | Diclofenac treatment in juvenile rheumatoid arthritis, with pharmacokinetics in 7 children aged 2-7 |
| 2235663 | 1990 | Open-label study | Pediatr Med Chir | Open non-comparative study of diclofenac in 26 patients (aged 2-16) with polyarticular juvenile chronic arthritis |
| 10756785 | 1997 | Comparative study/review | Rev Med Chir Soc Med Nat Iasi | Comparison of diclofenac, paduden and aspirin in 100 children with juvenile chronic arthritis |
| 8422565 | 1993 | Review | Br J Rheumatol | Diclofenac, ibuprofen, tolmetin and naproxen are comparably effective and tolerated for joint symptoms in children |
| 11735667 | 2001 | Review | Paediatr Drugs | Risks and benefits of NSAIDs in children compared with paracetamol |
| 1884567 | 1991 | Review | Clin Pharmacokinet | Pharmacokinetics of drugs used in juvenile arthritis |
| 17474954 | 2007 | Survey | Paediatr Anaesth | Diclofenac is licensed for juvenile rheumatoid arthritis in children over 1 year of age (UK context) |
| 723822 | 1978 | Clinical report | Minerva Pediatr | Sodium diclofenac in infantile rheumatoid arthritis (no abstract available) |
Other retrieved papers (case series on JIA with alveolar haemorrhage, nabumetone and naproxen reviews, a drug-delivery review, and an adult-onset Still's disease report) are not diclofenac-specific and are not tabulated.
Singapore Market Information
Diclofenac holds 20 valid single-ingredient licences. Approved indication text is not recorded in the available data. The first five are shown below:
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| SIN10523P | ULTRAFEN 12.5 SUPPOSITORY 12.5 mg | Suppository | Not stated |
| SIN09088P | APO-DICLO SR TABLET 75 mg | Film-coated tablet | Not stated |
| SIN09951P | RHEWLIN GEL 1% w/v | Gel | Not stated |
| SIN06145P | APO-DICLO TABLET 50 mg | Enteric-coated tablet | Not stated |
| SIN09672P | CLOFEC TABLET 25 mg | Film-coated tablet | Not stated |
Available routes and forms across all licences include oral tablets, topical gel, suppositories, injections and patches.
Safety Considerations
Contraindications (from knowledge-graph disease associations, not label text): hypertension, liver failure and liver disease, drug-induced liver injury, gallbladder disease, congestive heart failure, cardiovascular and heart disease, myocardial infarction, stroke and cerebrovascular disorders, peptic ulcer disease (including active), inflammatory bowel disease, asthma (including intrinsic and allergic), diabetes mellitus and diabetic ketoacidosis, blood coagulation disease, anaemia and haemoglobinopathy, substance abuse/dependence, and keratitis.
Drug Interactions: 100 interactions were identified. Those shown include:
- Moderate: hydrocortisone, dexamethasone, betamethasone, triamcinolone, budesonide (corticosteroids); acetylsalicylic acid; mesalazine and balsalazide; metformin; sulfonylureas (acetohexamide, chlorpropamide, glimepiride, glipizide); exenatide; aprepitant; fenfluramine and dexfenfluramine
- Minor: famotidine, ranitidine, cimetidine
Please also refer to the package insert for safety information, as label-based warnings and contraindications were not available for this report.
Conclusion and Next Steps
Decision: Hold for the rank 1 prediction (hypotrichosis simplex of the scalp); Proceed with Guardrails for juvenile idiopathic arthritis
Rationale:
- The rank 1 prediction and the other top-10 predictions, apart from JIA, rest only on graph-based scores. They have no trials, no literature and no clear mechanism, so they stay at Evidence Level L5.
- For JIA, diclofenac is mechanistically well matched and supported by small, older clinical studies and reviews (Evidence Level L3). It is a symptomatic option rather than a disease-modifying one, and no registered trials were found.
To proceed, the following is needed:
- Package insert warnings and contraindications from the HSA (currently a blocking data gap for safety screening)
- Detailed mechanism of action data
- Approved indication text for the Singapore licences
- Paediatric dosing and safety review, including GI, renal and cardiovascular monitoring and NSAID class precautions
- Confirmation of the Singapore paediatric labelling status
- More recent or higher-quality evidence (e.g., registered trials or modern comparative studies) for JIA
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.