Alfacalcidol
| Evidence Level: L5 | Predicted Indications: 3 |
Table of Contents
Alfacalcidol: From Hyperparathyroidism to Craniofacial Conodysplasia
One-Sentence Summary
Alfacalcidol is an active vitamin D analog. The TxGNN model’s top prediction is craniofacial conodysplasia, but no clinical trials and no publications support it. The best-supported lead among the predictions is renal tubular acidosis, which has 5 case reports and no trials.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Hyperparathyroidism, osteitis fibrosa, hypoparathyroidism, renal osteodystrophy (relations recorded in the knowledge graph; the local licence records contain no indication text) |
| Predicted New Indication | Craniofacial conodysplasia |
| TxGNN Prediction Score | 0.9955 |
| Evidence Level | L5 |
| India Market Status | Listed in a compiled Indian medicine price dataset (6 of 6) – CDSCO approval status is not included in this data |
| Number of Listed Products | 6 (valid: 6) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not currently available. Alfacalcidol is known as 1-alpha-hydroxycholecalciferol, an active vitamin D analog that acts on calcium and phosphate balance and bone mineralization.
The link to craniofacial conodysplasia, a rare skeletal dysplasia, is plausible only through general bone metabolism. No specific evidence supports it, and the prediction rests on the TxGNN model (deep learning) score alone, which may reflect similarities the model learned between related diseases, not biological evidence. The same applies to the second-ranked prediction, acromesomelic dysplasia (Campailla-Martinelli type, score 0.9953). That condition is a genetic disorder that typically involves growth-factor signaling, and vitamin D analog therapy has no established mechanism to correct such a defect, so its rationale is weak.
The third-ranked prediction, renal tubular acidosis (score 0.9927), is more biologically coherent. Chronic acidosis and phosphate wasting in this condition can cause osteomalacia and impaired vitamin D activation. Alfacalcidol supplies active vitamin D without needing renal activation, which may help bone mineralization. It would act on the secondary bone disease and not on the tubular acidification defect itself.
Clinical Trial Evidence
Currently no related clinical trials registered for craniofacial conodysplasia, nor for the other two predicted diseases.
Literature Evidence
No literature is available for craniofacial conodysplasia. For the third-ranked prediction, renal tubular acidosis, the data compiled for this report include five case reports, listed below for reference. They do not study the top-ranked disease.
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 22740247 | 2013 | Case report | Modern Rheumatology | Osteomalacia from RTA with Sjögren’s syndrome treated with sodium bicarbonate, risedronate, alfacalcidol and prednisolone. Bone density normalized by 24 months |
| 33398781 | 2021 | Case report | CEN Case Reports | Osteomalacia from atypical RTA with vitamin D deficiency, in a patient previously on active vitamin D |
| 28509074 | 2012 | Case report and review | CEN Case Reports | Osteomalacia secondary to distal RTA due to Sjögren’s syndrome |
| 11518137 | 2001 | Case report | Internal Medicine | Rapid osteomalacia improvement in a patient with Sjögren’s syndrome, rheumatoid arthritis and RTA type 1, treated with alkali and an alfacalcidol-containing regimen |
| 36412607 | 2023 | Case report and review | Kidney & Blood Pressure Research | Severe hypophosphatemia, Fanconi’s syndrome and distal RTA related to zoledronic acid |
In these reports alfacalcidol was used together with alkali therapy and other treatments, so its individual contribution cannot be separated.
India Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 2235 | Alphadol-C Soft Gelatin Capsule | Strip of 10 soft gelatin capsules | Not stated in the licence record |
| 1308 | Alphadol 0.5mcg Soft Gelatin Capsule | Strip of 10 soft gelatin capsules | Not stated in the licence record |
| 328 | Alphadol 0.25mcg Capsule | Strip of 10 soft gelatin capsules | Not stated in the licence record |
| 2489 | Alphadol 1mcg Soft Gelatin Capsule | Strip of 10 soft gelatin capsules | Not stated in the licence record |
| 64293 | Decalcid 0.25mcg Tablet | Strip of 10 tablets | Not stated in the licence record |
A sixth licence (235436, Vitalpha Soft Gelatin Capsule) is also valid. All six are oral single-ingredient products.
Safety Considerations
Please refer to the package insert for safety information.
Conclusion and Next Steps
Decision: Hold
Rationale: The top-ranked prediction, craniofacial conodysplasia, rests only on a model score, with no trials or publications, so the evidence level is L5. The only supporting literature concerns renal tubular acidosis, and it consists of case reports in which alfacalcidol was combined with other treatments. That is a research question and not a basis for advancing the top prediction.
To proceed, the following is needed:
- Mechanism of action data for alfacalcidol
- Package insert warnings and contraindications from the licence holders, since no safety data are available
- Any published or registered studies on craniofacial conodysplasia, or a decision to prioritize renal tubular acidosis for a structured literature review or controlled study
- Confirmation of the approved indication text for the Indian licences
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.