Efavirenz

證據等級: L5

預測適應症: 3 個

Efavirenz: From HIV-1 Infection to Simian Immunodeficiency Virus Infection

One-Sentence Summary

Efavirenz is a non-nucleoside reverse transcriptase inhibitor (NNRTI) whose established pharmacological class targets HIV-1 infection in humans. The TxGNN model predicts a possible application to Simian Immunodeficiency Virus (SIV) Infection, but the supporting evidence — 1 clinical trial (withdrawn, low relevance) and 16 publications — largely describes efavirenz being used as a research tool in an engineered SIV/HIV-1 chimeric virus model (RT-SHIV) rather than demonstrating native efficacy against wild-type SIV. Current evidence is preliminary and requires careful reinterpretation before advancing.

Quick Overview

Item	Content
Original Indication	Not formally documented (efavirenz is not marketed in Finland; no license text available). Its established pharmacological class is NNRTI antiretroviral therapy for HIV-1 infection
Predicted New Indication	Simian Immunodeficiency Virus Infection
TxGNN Prediction Score	99.80%
Evidence Level	L3
Finland Market Status	✗ Not Marketed
Number of Authorizations	0
Recommended Decision	Hold

Why is This Prediction Reasonable?

Detailed mechanism-of-action data for efavirenz is not available in this evidence pack. Based on the information that is available (from the repurposing rationale), efavirenz is known to act as an NNRTI, binding a non-nucleoside pocket on the HIV-1 reverse transcriptase (RT) enzyme to block viral replication.

The predicted link to SIV infection, however, needs careful interpretation. Wild-type SIV reverse transcriptase differs substantially from HIV-1 RT, and NNRTIs such as efavirenz are generally not effective against native SIV. The clinical and preclinical evidence collected here almost entirely concerns "RT-SHIV" — a laboratory-engineered chimeric virus in which SIV's own RT gene has been replaced with HIV-1's RT gene, specifically so that researchers can study HIV-1 NNRTI drugs (including efavirenz) and resistance dynamics in a nonhuman-primate (macaque) model. In other words, this evidence supports "efavirenz used as a tool to study an engineered HIV-1-RT-carrying virus in animals," not "efavirenz has native antiviral activity against SIV." This distinction is central to interpreting the TxGNN score and should not be conflated with a genuine new indication.

For context, TxGNN also flagged two additional low-confidence candidates for efavirenz in this run: feline acquired immunodeficiency syndrome (FIV; Evidence Level L5, based on an in vitro structural comparison study showing likely low cross-species affinity) and an ultra-rare genetic neurodevelopmental disorder (Evidence Level L5, no clinical or literature evidence at all). Both were scored "Hold" and are not carried further in this report.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT00863668	N/A	Withdrawn	0	Studied HIV/SIV viral decay kinetics with the integrase inhibitor raltegravir, not efavirenz; trial was withdrawn with zero enrollment. Relevance graded "C" (low) — flagged as a likely search-mapping artifact rather than direct efavirenz evidence

Literature Evidence

PMID	Year	Type	Journal	Key Findings
15328115	2004	Animal Study	Antimicrob Agents Chemother	First demonstration of efavirenz antiviral activity in rhesus macaques infected with RT-SHIV (SIV/HIV-1 RT chimera)
15919889	2005	Animal Study	J Virology	HAART regimen (efavirenz 200 mg + lamivudine + tenofovir) suppressed RT-SHIV viral load in rhesus macaques
19889213	2009	Animal Study	Retrovirology	Short-course efavirenz monotherapy followed by combination ART studied in RT-SHIV-infected pigtail macaques; tracked resistant subpopulation dynamics
21084490	2011	Preclinical/Virology	J Virology	Genetic diversity of RT-SHIV persists in macaques despite ART, including efavirenz monotherapy phases
24777106	2014	Animal Study	Antimicrob Agents Chemother	Enhanced 4–5 drug HAART regimens improved RT-SHIV viral decay kinetics in rhesus macaques
20032180	2010	Preclinical/Virology	J Virology	Characterized viral sanctuary sites during HAART in the RT-SHIV nonhuman primate AIDS model
20668516	2010	Preclinical/Virology	PLoS One	Viral decay kinetics characterized in HAART-treated RT-SHIV rhesus macaque AIDS model
15564466	2004	In vitro	J Virology	In vitro characterization of the SIV-HIV RT-SHIV chimera developed to study NNRTI antiviral resistance in pigtail macaques
22933296	2012	Preclinical/Virology	J Virology	Ultrasensitive allele-specific PCR detected rare pre-existing drug-resistant RT-SHIV variants in macaques
35856680	2022	In vitro/Imaging	Antimicrob Agents Chemother	Mass spectrometry imaging mapped distribution of 6 antiretrovirals (including efavirenz-class agents) relative to RT-SHIV RNA and fibrosis in macaque spleens

Note: All ten publications concern the RT-SHIV engineered chimeric virus model used for HIV-1 drug research in nonhuman primates, not native SIV disease.

Finland Market Information

Efavirenz is currently not marketed in Finland — no marketing authorizations are on record (total_licenses: 0), so no product/license table can be generated.

Safety Considerations

Please refer to the package insert for safety information.

Conclusion and Next Steps

Decision: Hold

Rationale: The only clinical trial identified is irrelevant (wrong drug, withdrawn, zero enrollment), and the literature base — while numerous (10+ publications) — almost entirely describes efavirenz's use as a research reagent in an artificially engineered RT-SHIV virus rather than evidence of activity against native SIV. Combined with a Blocking-severity data gap on TFDA package insert/safety data (DG001), the candidate cannot yet advance to the S1 safety pre-assessment stage.

To proceed, the following is needed:

TFDA/regulatory package insert data (warnings, contraindications) — currently blocking (DG001)
Confirmed mechanism-of-action documentation via DrugBank (DG002)
Clarification of whether "SIV infection" represents a genuine translatable indication or solely reflects RT-SHIV research-tool overlap with efavirenz's existing HIV-1 indication
If veterinary application (FIV) is of interest, dedicated species-specific pharmacokinetic and RT-binding affinity data, given the current L5 evidence level and low predicted cross-species activity
Disclaimer

This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.