Adapalene
| Evidence Level: L5 | Predicted Indications: 1 |
Table of Contents
Adapalene: topical retinoid (RAR-β/γ agonist) → zinc, elevated plasma
One-Sentence Summary
Adapalene is a topical retinoid used on the skin. The TxGNN model predicts it may be relevant to elevated plasma zinc, but no clinical trials and no publications currently support this direction, so it rests on a model prediction alone.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Not recorded in the local data |
| Predicted New Indication | zinc, elevated plasma |
| TxGNN Prediction Score | 0.9951 |
| Evidence Level | L5 |
| Canada Market Status | Marketed (marketed DINs: 10 of 10) |
| Number of DINs | 10 (marketed: 10) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism-of-action data for adapalene are not available in the data compiled for this report. From general pharmacology, adapalene is a topical retinoid that selectively binds retinoic acid receptors (RAR-β and RAR-γ) and modulates keratinocyte differentiation and inflammation.
Elevated plasma zinc (hyperzincemia) is a biochemical state, typically caused by excess zinc intake, certain genetic variants, or altered zinc-binding protein levels. No known pathway links RAR signalling to systemic zinc homeostasis in a way that would support therapeutic use. The high score of 0.9951 most likely reflects network proximity in the model (for example shared zinc- or retinoid-related gene and protein associations) rather than biological or clinical validity. Adapalene is also applied topically with low systemic absorption, so an effect on plasma zinc is improbable. The prediction should be treated as a weak, unvalidated hypothesis.
Canada Market Information
| DIN | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 02148749 | DIFFERIN | Not recorded | Not recorded |
| 02274000 | DIFFERIN XP | Not recorded | Not recorded |
| 02231592 | DIFFERIN | Not recorded | Not recorded |
| 02517205 | SANDOZ ADAPALENE / BENZOYL PEROXIDE FORTE | Not recorded | Not recorded |
| 02456923 | TARO-ADAPALENE/BENZOYL PEROXIDE | Not recorded | Not recorded |
Ten valid licences are on record; the five main ones are listed above.
Safety Considerations
- Drug Interactions: 58 potential interactions were identified in the interaction database, all with an unspecified severity level. Examples include doxycycline, minocycline, tetracycline, metronidazole, prednisone, triamcinolone, budesonide, ibuprofen and fluconazole.
Please refer to the package insert for further safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The prediction has a high model score but no supporting clinical trials or literature, no plausible mechanistic link between retinoid receptor signalling and plasma zinc, and minimal systemic exposure from topical use.
To proceed, the following is needed:
- Any study directly addressing adapalene and plasma zinc levels
- Mechanism-of-action data and a plausible biological pathway
- Package insert warnings and contraindications from Health Canada
- Evidence on systemic absorption and route compatibility for a systemic condition
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.