Dl-Alpha-Tocopherol
| 證據等級: L5 | 預測適應症: 10 個 |
目錄
DL-alpha-Tocopherol: From Antioxidant Supplement to Immature Cataract
One-Sentence Summary
DL-alpha-Tocopherol is the synthetic racemic form of Vitamin E, a fat-soluble antioxidant widely used to protect cells from oxidative stress damage. The TxGNN model predicts it may be effective for Immature Cataract, with 0 clinical trials and 1 observational study currently supporting this direction.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | No formally registered indication (used as nutritional antioxidant supplement) |
| Predicted New Indication | Immature Cataract |
| TxGNN Prediction Score | 99.975% |
| Evidence Level | L4 |
| South Africa Market Status | Not Marketed |
| Number of SAHPRA Registrations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available from the DrugBank record for this compound. Based on well-established pharmacological knowledge, DL-alpha-Tocopherol is the synthetic racemic form of Vitamin E — a lipid-soluble, chain-breaking free radical scavenger. It neutralises reactive oxygen species (ROS) by donating a hydrogen atom to lipid peroxy radicals, thereby interrupting the peroxidation cascade in cell membranes. It also works synergistically with the reduced glutathione (GSH) system and glutathione peroxidase (GSH-Px) to maintain the cellular redox balance.
Immature cataract is characterised by progressive, partial opacification of the lens due to oxidative cross-linking of crystallin proteins and lipid peroxidation in lens epithelial cells. These tissues are continuously exposed to light-induced oxidative stress, making the antioxidant defence network particularly critical. The primary pathological mechanism — ROS-driven protein aggregation — directly aligns with alpha-tocopherol’s established antioxidant action. This mechanistic overlap provides the biological basis for the TxGNN prediction.
It should be noted, however, that mechanistic plausibility does not equate to clinical efficacy. The sole supporting study in this evidence pack is a small observational trial conducted in 1999 (n=50), with no randomised controlled trials specifically evaluating DL-alpha-Tocopherol in immature cataract. Advancing this candidate requires prospective clinical investigation.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 10749028 | 1999 | Cohort/Observational | Annals of Nutrition & Metabolism | 50 patients with unilateral/bilateral idiopathic immature senile cataract (cortical n=25, nuclear n=25) received Vitamin E (n=12 per subgroup) or placebo (n=13 per group) for 30 days; study measured GSH, MDA, and GSH-Px levels in lens homogenates as markers of oxidative stress |
South Africa Market Information
DL-alpha-Tocopherol (DrugBank ID: DB14476) is not currently registered with SAHPRA and holds no active product licences in South Africa. There are no approved dosage forms or registered indications on record.
Safety Considerations
Please refer to the SAHPRA-approved Professional Information (PI) for safety information. Report adverse drug reactions to SAHPRA.
Conclusion and Next Steps
Decision: Hold
Rationale: Although the mechanistic link between alpha-tocopherol’s antioxidant properties and immature cataract prevention is biologically plausible, the current evidence base is limited to a single small observational study from 1999. This is insufficient to advance beyond a research question stage, and the compound carries no SAHPRA registration in South Africa.
To proceed, the following is needed:
- Retrieve the full DrugBank MOA record (DG002) to formally document the pharmacological rationale
- Obtain SAHPRA-approved Professional Information (PI) and full safety/contraindication data (DG001) as a blocking prerequisite for safety screening
- Commission or identify prospective Phase 2/3 randomised controlled trials evaluating DL-alpha-Tocopherol specifically in immature cataract populations
- Define the appropriate delivery route (oral supplementation versus topical ocular formulation) and target dose range for this indication
- Conduct a formal drug–drug interaction review for commonly co-prescribed medications in the target population (elderly patients with concurrent cardiovascular or metabolic conditions)
- Evaluate whether existing Vitamin E (alpha-tocopherol) products registered under other indications in South Africa could support a compassionate use or section 21 authorisation pathway
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.