Zidovudine

證據等級: L5

預測適應症: 6 個

Zidovudine: From HIV/AIDS Antiretroviral Therapy to Prevention of Congenital HIV Transmission

One-Sentence Summary

Zidovudine (AZT) is the original nucleoside reverse transcriptase inhibitor (NRTI), long established for treating HIV-1 infection/AIDS. Of six indications TxGNN predicted in this evidence pack, Congenital Human Immunodeficiency Virus (perinatal / mother-to-child transmission prevention) is the only candidate with strong, credible support — 33 clinical trials and 20 publications, including the landmark ACTG 076/PACTG-derived prophylaxis regimens. This largely reflects zidovudine's already-established PMTCT role rather than a genuinely novel indication; the other five predictions in this batch (feline/simian AIDS animal models, a rare neurodevelopmental disorder, and an obsolete hyperlipidemia ontology term) lack credible human clinical relevance and are not recommended for further evaluation (see "Other Predicted Indications Screened" below).

Quick Overview

Item	Content
Original Indication	Not available from Finland licensing data (drug not marketed there); based on general pharmacological knowledge — HIV-1 infection / AIDS (adult antiretroviral therapy)
Predicted New Indication	Congenital Human Immunodeficiency Virus (perinatal/mother-to-child transmission prevention)
TxGNN Prediction Score	99.19%
Evidence Level	L1
Finland Market Status	✗ Not marketed
Number of Authorizations	0
Recommended Decision	Proceed with Guardrails

Why is This Prediction Reasonable?

Currently, detailed mechanism of action data is not available from DrugBank for this record. Based on well-established pharmacological knowledge, zidovudine is a thymidine nucleoside analogue reverse transcriptase inhibitor (NRTI): it is phosphorylated intracellularly to its active triphosphate form, which is incorporated into nascent viral DNA by HIV-1 reverse transcriptase, causing chain termination and blocking viral replication. Its efficacy in adult HIV-1 infection/AIDS has been established since 1987 (the first antiretroviral drug ever approved).

Mechanistically, the same reverse-transcriptase-blocking action applies directly to interrupting mother-to-child (in-utero, intrapartum, and early neonatal) transmission of HIV-1 — the virus and its reverse transcriptase are identical; only the patient population (pregnant women and neonates) differs. This is reflected in real regulatory history: the landmark ACTG 076/PACTG 076 trial established that zidovudine prophylaxis (given antepartum/intrapartum to the mother and for six weeks to the newborn) reduces perinatal HIV transmission by roughly two-thirds, becoming the founding evidence base for PMTCT programs worldwide.

Because this evidence pack's original_indications field is empty (a documented drug-level data gap, DG002), the model's "predicted new indication" substantially overlaps with zidovudine's already-recognized antiretroviral/PMTCT role rather than a true off-label repurposing opportunity. This should be read as a data-completeness artifact rather than a novel scientific hypothesis — the underlying clinical evidence is nonetheless strong.

Clinical Trial Evidence

Trial Number	Phase	Status	Enrollment	Key Findings
NCT00386230	Phase 3	Completed	1,554	Short-course ZDV regimen non-inferior to long ACTG-076-like regimen for reducing perinatal HIV transmission risk in Thailand
NCT00000751	Phase 3	Completed	1,600	Evaluated HIVIG vs IVIG added to intrapartum/neonatal AZT for further reducing maternal-fetal HIV transmission
NCT01061151	Phase 3	Completed	3,747	PROMISE study — optimal antiretroviral strategies (incl. AZT-based regimens) for antepartum, intrapartum, and postpartum/breastfeeding MTCT prevention
NCT00164736	Phase 3	Completed	2,369	Maternal/infant antiretroviral interventions and nutritional supplementation during breastfeeding to prevent MTCT
NCT00197587	N/A	Completed	1,200	"Mashi" study — prevention of milk-borne HIV-1C transmission in Botswana
NCT01511237	Phase 3	Completed	379	PHPT-5 — perinatal antiretroviral intensification for women with <8 weeks of prior HAART during pregnancy
NCT00102960	Phase 3	Completed	377	Compared antiretroviral course lengths for infants infected with HIV at birth, in a resource-poor setting
NCT00001007	Phase 1	Completed	18	Safety and pharmacokinetics of IV and oral zidovudine in infants with perinatal HIV exposure (age 1 day–3 months)
NCT03642704	Phase 4	Completed	56	Strategy evaluation of early HIV diagnosis plus reinforced preventive antiretroviral treatment at birth (Guinea)

Literature Evidence

PMID	Year	Type	Journal	Key Findings
7913986	1994	Guideline	MMWR Recomm Rep	US PHS Task Force recommendations for ZDV use to reduce perinatal HIV transmission, based on ACTG 076 results (~2/3 risk reduction)
8879761	1996	Review	Clin Infect Dis	Progress report two years post-ACTG 076: real-world MTCT rates fell substantially when counseling and ZDV therapy were offered
9240849	1997	Cohort	Acta Paediatr Suppl	Timing of perinatal HIV transmission and its implications for designing ZDV-based preventive/therapeutic interventions
12197800	2002	Cohort	Arch Pediatr Adolesc Med	Population-level effectiveness of zidovudine prophylaxis on mother-to-infant HIV-1 transmission, before vs. after its introduction
8419601	1993	Phase I trial	J Pediatr	Safety, tolerability, and pharmacokinetics of IV/oral zidovudine in 32 infants born to HIV-infected mothers
28537936	2017	Cohort/registry	AIDS	Assessed association between zidovudine use in pregnancy and congenital malformations; evidence inconsistent for increased risk
26687320	2016	Registry study	Eur J Obstet Gynecol Reprod Biol	Antiretroviral Pregnancy Registry data on prenatal ZDV exposure and risk of ventricular septal/congenital heart defects
33541012	2021	Systematic review/meta-analysis	Epidemiol Health	Meta-analysis on whether antiretroviral therapy (incl. ZDV) during pregnancy causes congenital malformations
40011239	2025	Case/non-case study	Eur J Clin Pharmacol	European congenital anomaly registry analysis of antiretroviral drug exposure in pregnancy and malformation risk
2126136	1990	Case report	Pediatr Infect Dis J	Early case report describing zidovudine treatment of an infant with congenital HIV infection

Finland Market Information

Zidovudine is not currently marketed in Finland — the regulatory query returned 0 valid marketing authorizations, so no product name, dosage form, or approved-indication text is available. Any repurposing pathway would require a new marketing authorization application (or import/named-patient route) before local use.

Other Predicted Indications Screened

Five additional TxGNN predictions were reviewed in this evidence pack and are not recommended for further evaluation:

Disease	Score	Evidence Level	Reason for Exclusion
Feline acquired immunodeficiency syndrome	99.96%	L4	Cross-species knowledge-graph artifact (feline FIV model); no human clinical relevance
Simian immunodeficiency virus infection	99.96%	L4	Primate disease model used as an HIV analogue in preclinical research; not a human indication
Neurodevelopmental disorder with ataxic gait, absent speech, decreased cortical white matter	99.96%	L5	No mechanistic link, no supporting trials or literature; likely embedding-similarity false positive
Obsolete familial combined hyperlipidemia	99.62%	L5	Ontology term marked "obsolete"; no known lipid-related mechanism, zero evidence
AIDS related complex	99.19%	L1	Same underlying finding as the reported indication above — reflects AZT's already-established antiretroviral role, not a novel candidate

Safety Considerations

Please refer to the package insert for safety information. Key warnings, contraindications, and drug-drug interaction data were not available in this evidence pack (TFDA/Fimea package insert query pending — flagged as a Blocking data gap, DG001).

Conclusion and Next Steps

Decision: Proceed with Guardrails

Rationale: The clinical evidence base for zidovudine in preventing congenital/perinatal HIV transmission is strong (L1: 33 trials including multiple large completed Phase 3 studies, plus 20 publications spanning efficacy and pregnancy-safety literature). However, this substantially overlaps with the drug's already-established antiretroviral/PMTCT use rather than representing a genuinely new indication, and two blocking data gaps prevent a full go decision: local (Finland) package-insert safety data and formal MOA documentation are both missing, and the drug is not currently marketed in Finland.

To proceed, the following is needed:

TFDA/Fimea package insert (warnings, contraindications) — Blocking, required for initial safety screening (S1)
Formal DrugBank/regulatory-sourced mechanism of action documentation
Clarification of true original approved indication(s), since original_indications is currently empty in source data
Regulatory pathway assessment for Finland market entry (new MA application or import route), given 0 current licenses
Confirmation that the "new indication" framing (PMTCT-specific) offers meaningful clinical/regulatory differentiation from AZT's existing antiretroviral use before committing further repurposing resources
Disclaimer

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