Abacavir
| Evidence Level: L5 | Predicted Indications: 3 |
Table of Contents
Abacavir: From HIV Infection / AIDS to Simian Immunodeficiency Virus Infection
One-Sentence Summary
Abacavir is a nucleoside reverse transcriptase inhibitor originally used to treat HIV infection and AIDS. The TxGNN model predicts it may be effective for simian immunodeficiency virus (SIV) infection, a non-human primate disease model. Support is limited to 0 clinical trials and 1 in vitro publication, so this is largely a knowledge-graph extension of the original HIV use rather than a true human repurposing opportunity.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | HIV infectious disease; AIDS (from the knowledge graph, because no approved indication text is available in the New Zealand licence records) |
| Predicted New Indication | Simian immunodeficiency virus infection |
| TxGNN Prediction Score | 99.79% |
| Evidence Level | L4 (preclinical / in vitro evidence only) |
| New Zealand Market Status | Cancelled only (no currently valid licences) |
| Number of Authorizations | 2 (both cancelled) |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Detailed mechanism of action data is not currently available in the data compiled for this report. Based on known pharmacology, abacavir is a nucleoside reverse transcriptase inhibitor. It is phosphorylated inside cells to carbovir triphosphate, which terminates proviral DNA chain elongation.
SIV is a lentivirus closely related to HIV and has a homologous reverse transcriptase, so mechanistic plausibility is high. The high TxGNN score most likely reflects this viral similarity to HIV rather than a genuinely new therapeutic opportunity. SIV infection is a non-human primate model, not a human clinical indication.
Two other predictions were also generated:
- Feline acquired immunodeficiency syndrome (score 99.79%, L4): FIV is also a lentivirus whose reverse transcriptase can be inhibited by NRTIs. Evidence is a 2002 in vitro study of zidovudine, lamivudine and abacavir against FIV. This is a veterinary condition with limited relevance to human medicine.
- Neurodevelopmental disorder with ataxic gait, absent speech, and decreased cortical white matter (score 99.78%, L5): No mechanistic link, clinical trials or literature were identified. This is a rare genetic disorder with no established relevance to abacavir's mechanism, so the prediction is speculative.
Clinical Trial Evidence
Currently no related clinical trials registered.
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 15040537 | 2004 | In vitro susceptibility study | Antiviral Therapy | Tested 16 approved anti-HIV drugs and one experimental drug against HIV-2, SIV and SHIV strains to inform treatment and post-exposure prophylaxis |
New Zealand Market Information
| Authorization Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 378038 | Ziagen (cancelled) | Tab 300 mg | Not available |
| 2632365 | Abacavir/Lamivudine Viatris (cancelled) | Tab 600 mg with lamivudine 300 mg | Not available |
Safety Considerations
- Knowledge-graph contraindications (from drug-disease contraindication links, not package insert text): liver failure, liver disease, fatty liver disease, non-alcoholic steatohepatitis, kidney disease, pancreatitis, gallbladder disease, pyoureter, lactic acidosis, neutropenia, agranulocytosis, anaemia (including macrocytic anaemia), hypertriglyceridaemia, obesity disorders, myopathy and other muscle diseases (including myositis, dermatomyositis, familial periodic paralysis).
- Drug Interactions: 93 interactions are recorded in total. The two rated Moderate are naltrexone and orlistat. Many others (for example metformin, morphine, omeprazole, pantoprazole, prednisone, vancomycin, amphotericin B) have no severity rating.
- Additional consideration: abacavir carries a recognised risk of HLA-B*57:01-associated hypersensitivity.
Please refer to the package insert for full warnings and contraindications; the New Zealand package insert data could not be retrieved for this report.
Conclusion and Next Steps
Decision: Hold
Rationale: The only support is indirect in vitro evidence for a non-human primate model, with no clinical trials. The prediction mostly restates abacavir's existing anti-HIV activity, and the product is no longer actively licensed in New Zealand.
To proceed, the following is needed:
- Retrieval and review of the Medsafe package insert (warnings and contraindications), which is a blocking gap for safety screening
- Mechanism of action data from DrugBank
- A clear human clinical rationale, since SIV and FIV are animal conditions
- Mechanistic validation if the neurodevelopmental disorder prediction is to be pursued
- Confirmation of current regulatory and supply status in New Zealand, since both licences are cancelled
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.