Losartan
| 證據等級: L5 | 預測適應症: 8 個 |
目錄
Losartan: From Hypertension to Malignant Renovascular Hypertension
One-Sentence Summary
Losartan is an angiotensin II receptor blocker (ARB), a drug class established for treating hypertension. The TxGNN model predicts it may be effective for Malignant Renovascular Hypertension, but this is currently supported only by mechanistic reasoning and 2 low-tier publications (a case report and a preclinical study) — no dedicated clinical trials exist for this indication.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Hypertension (ARB class — not independently confirmed by SAHPRA registration data in this evidence pack; see note below) |
| Predicted New Indication | Malignant Renovascular Hypertension |
| TxGNN Prediction Score | 99.73% |
| Evidence Level | L4 |
| South Africa Market Status | Not marketed |
| Number of SAHPRA Registrations | 0 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is flagged as a data gap in this pack. Based on known pharmacology, losartan is an angiotensin II type 1 (AT1) receptor antagonist that directly blocks the renin-angiotensin-aldosterone system (RAAS) — the pathway central to the pathophysiology of malignant and renovascular hypertension.
The mechanistic rationale supplied with this prediction notes that AT1 blockade is pharmacologically well-matched to malignant renovascular hypertension’s disease biology. A supporting animal-model study (PMID 30809002, linked to the closely related predicted indication “malignant hypertensive renal disease”) independently validates the angiotensin II / NF-κB pathway as pathogenic in this disease model, lending indirect mechanistic support.
However, this same mechanistic pathway carries a well-recognized clinical caveat: ARBs are known to risk precipitating acute kidney injury in patients with bilateral renal artery stenosis. This is an established safety consideration for the drug class in this population, not a new finding — it must be weighed alongside the therapeutic rationale.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 10667645 | 2000 | Case Report | Angiology | Enalapril + losartan improved blood pressure in a Takayasu’s arteritis patient with malignant hypertension due to renal artery stenosis, refractory to conventional treatment and not amenable to angioplasty |
| 22294399 | 2009 | Preclinical/Animal (SHR model) | Current Protocols in Pharmacology | Methodological protocol for assessing antihypertensive activity in conscious-rat hypertension models; not losartan-specific efficacy data |
South Africa Market Information
No SAHPRA registration records are present in this evidence pack — losartan is recorded as not currently marketed under this dataset (0 registrations). Market status should be independently verified against the current SAHPRA register before any further action.
Safety Considerations
Please refer to the SAHPRA-approved Professional Information (PI) for safety information. Report adverse drug reactions to SAHPRA.
Known class-effect risk (from evidence rationale, not from SAHPRA PI data): ARBs, including losartan, carry a recognized risk of precipitating acute kidney injury in patients with bilateral renal artery stenosis — directly relevant given the predicted indication involves renovascular pathology. This should be a specific focus once formal PI/safety data is obtained.
Conclusion and Next Steps
Decision: Hold
Rationale: A Blocking-severity data gap (missing SAHPRA/TFDA-equivalent PI warnings and contraindications) prevents this candidate from even entering the S1 safety review stage. Evidence is limited to L4 (a single case report and an unrelated preclinical methods paper), with no clinical trials, and the drug has zero current SAHPRA registrations in this dataset.
To proceed, the following is needed:
- SAHPRA-approved Professional Information (warnings, contraindications, drug interactions) to complete the S1 safety review
- Confirmed original indication and MOA data for losartan from an authoritative source
- Targeted evaluation of AKI risk in renal artery stenosis populations before considering this indication further
- Dedicated clinical evidence (case series or trial data) specific to losartan in malignant renovascular hypertension, beyond the single case report currently available
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.