ttd

is an Aggregator.

The Therapeutic Target Database (TTD) is a comprehensive aggregator providing information about known and explored therapeutic protein and nucleic acid targets, targeted diseases, pathway information, and corresponding drugs directed at these targets. TTD 2024 includes extensive druggability information across three perspectives: molecular interactions/regulations, human system profiles, and cell-based expression variations. The database encompasses 3,730 targets (including 532 successful, 1,442 clinical trial, 239 preclinical/patented, and 1,517 literature-reported targets) and 39,862 drugs, with druggability characteristics covering ligand-specific binding pockets, protein-protein interaction networks, microbiota-drug regulations, target similarity profiles, pathway involvements, tissue distributions, and cell-based expression variations across different diseases and perturbations.

Domains

biomedical, drug discovery, genomics, proteomics, pharmacology

License

Freely accessible for research and educational purposes

Homepage

ttd

Repository

Unknown

Infores ID

infores:ttd

FAIRsharing ID

Unknown

Product Summary

Products

From this Resource
ID Name URL Category Format Description
ttd.portal TTD Web Portal ttd GraphicalInterface http Main web portal for browsing and sear...
ttd.targets-raw ⚠ TTD Targets Information P1-01-TTD_target_download.txt Product txt Raw format target information includi...
ttd.drugs-raw ⚠ TTD Drug Information P1-02-TTD_drug_download.txt Product txt Raw format drug information including...
ttd.crossmatch ⚠ Cross-matching Drug IDs P1-03-Drug_xrefs.txt Product txt Cross-matching identifiers between TT...
ttd.synonyms ⚠ Drug Synonyms P1-04-Drug_synonyms.txt Product txt Synonyms of drugs and small molecules...
ttd.drug-disease ⚠ Drug-Disease Mapping P1-05-Drug_disease.txt Product txt Drug to disease mapping with ICD iden...
ttd.target-disease ⚠ Target-Disease Mapping P1-06-Target_disease.txt Product txt Target to disease mapping with ICD id...
ttd.target-drug ⚠ Target-Drug Mapping P1-07-Drug-TargetMapping.xlsx Product csv Target to drug mapping with mode of a...
ttd.biomarker-disease ⚠ Biomarker-Disease Mapping P1-08-Biomarker_disease.txt Product txt Biomarker to disease mapping with ICD...
ttd.target-compound ⚠ Target-Compound Activity Data P1-09-Target_compound_activity.txt Product txt Target to compound mapping with exper...
ttd.uniprot-all ⚠ All Target UniProt IDs P2-01-TTD_uniprot_all.txt Product txt UniProt IDs for all targets in TTD
ttd.sequences-all ⚠ All Target Sequences P2-06-All_target_seq.txt Product fasta Sequence data for all targets in FAST...
ttd.structures-all ⚠ All Drug Structures P3-01-Drug_structure.sdf Product sdf Structure data for all drugs in SDF f...
ttd.smiles-inchi Drug SMILES and InChI P3-06-Drug_SMILE_InChI.txt Product txt SMILES and InChI representations for ...
ttd.kegg-pathways ⚠ Target KEGG Pathways P4-01-Target_KEGG_pathway.txt Product txt KEGG pathway data for all targets
ttd.wiki-pathways Target WikiPathways P4-06-Target_wikipathway.txt Product txt WikiPathways data for all targets
ttd.drug-combinations ⚠ Drug Combinations P5-01-Drug_combination_synergism_anti-counteractive.txt Product txt Drug combination data including syner...
ttd.help ⚠ TTD Help Documentation help DocumentationProduct http Help documentation and user guide for...
From other Resources
ID Name URL Category Format Description
pharmkg.graph PharmKG graph 4077338 GraphProduct ❔ Cleaned benchmark graph (PharmKG-8k) ...
translator.ttd.graph Translator TTD KGX Graph latest GraphProduct kgx-jsonl KGX JSONL graph package for TTD distr...
translator.translator_kg.graph Translator Aggregate KGX Graph latest GraphProduct kgx-jsonl Aggregated KGX JSONL graph package co...

Details

Therapeutic Target Database

Overview

The Therapeutic Target Database (TTD) is a comprehensive aggregator providing specialized information about therapeutic protein and nucleic acid targets, their targeted diseases, pathway information, and corresponding drugs. TTD serves as an essential resource for drug discovery and development, facilitating target assessment, validation, and druggability evaluation.

Mission and Scope

TTD’s primary mission is to facilitate research and early development of targeted therapeutics by providing comprehensive druggability information for therapeutic targets. The database aggregates and integrates data from multiple sources including FDA approvals, clinical trial databases (ClinicalTrials.gov), pharmaceutical company pipeline reports, patent databases, and scientific literature.

Database Content

Targets and Drugs

As of the 2024 update, TTD contains:

  • 3,730 therapeutic targets categorized by development status:
    • 532 successful targets (targeted by FDA-approved drugs)
    • 1,442 clinical trial targets
    • 239 preclinical/patented targets
    • 1,517 literature-reported targets
  • 39,862 drugs across development stages:
    • 2,895 approved drugs
    • 11,796 clinical trial drugs
    • 5,041 preclinical/patented drugs
    • 20,130 experimental drugs

Druggability Information

TTD 2024 introduces comprehensive druggability characteristics from three distinct perspectives:

1. Molecular Interactions and Regulations

  • Ligand-Specific Binding Pockets: Over 22,431 co-crystal structures providing drug binding pocket information for 1,237 targets, with residues interacting with drugs at distances <5Å highlighted
  • Protein-Protein Interaction Networks: Network properties (degree, betweenness centrality, clustering coefficient, etc.) calculated for 2,163 targets based on a human PPI network of 9,309 proteins and 52,713 interactions
  • Microbiota-Drug Bidirectional Regulations: 9,812 interactions between 663 drugs and 686 microbes across 20 phyla, describing how microbiota affects drug metabolism and how drugs regulate microbe abundance

2. Human System Features

  • Target Similarity Profiles: Similarity to human proteins outside target families calculated via BLAST (E-value <0.005) for 3,005 targets, helping assess off-target interactions
  • Pathway Involvements: 241 life-essential KEGG pathways associated with 2,881 targets, indicating target positions in critical biological processes
  • Tissue/Organ Distributions: Protein expression data across 32 human tissues for 2,001 targets, helping evaluate potential adverse drug reactions

3. Cell-Based Expression Variations

  • Varied Expressions Across Cell Types: Expression profiles for 2,845 targets across 1,742 cell types from 7,289 samples, covering 121 disease classes defined by WHO ICD-11
  • Exogenous Stimulus-Induced Differential Expression: Expression changes induced by 625 exogenous factors (drugs, infections, environmental stimuli) for 2,862 targets across 313 cell lines
  • Endogenous Factor-Modified Expression: Expression alterations by 447 endogenous factors (mutations, expression variations) for 2,841 targets across 198 cell lines

Data Organization and Access

Search and Browse Functions

TTD provides multiple search interfaces:

  • Full-text search across targets and drugs
  • Search by ICD-11 defined disease classes
  • Biomarker search
  • Drug scaffold search
  • Batch search for multiple TTD IDs

Downloadable Data

TTD offers comprehensive downloadable datasets including:

  • Target Information: UniProt IDs, sequences (FASTA), pathway data (KEGG and WikiPathways) for all targets or filtered by development status
  • Drug Information: Structures (SDF format), SMILES/InChI representations, biologic drug sequences, cross-references to public databases
  • Mapping Data: Target-disease, drug-disease, biomarker-disease, target-drug, and target-compound activity mappings
  • Drug Combinations: Synergistic, additive, and antagonistic drug combination data with mechanistic classifications
  • Synonym Data: Comprehensive synonyms for drugs and small molecules

Key Features and Updates

2024 Update Highlights

The TTD 2024 update significantly expanded druggability information:

  • Nine categories of druggability characteristics collected via systematic review
  • Druggability data organized into three perspectives: molecular, system, and cellular
  • Batch search functionality for uploading lists of TTD IDs
  • Full download capability for all search results
  • Enhanced cross-linking to pathway databases

Historical Development

TTD has undergone continuous enhancement since 2002:

  • 2022: Added structure-based activity landscapes, prodrug information, co-target data
  • 2020: Integrated target regulators (microRNAs, transcription factors), patented agents with activity values
  • 2018: Incorporated differential expression profiles in patients vs. healthy individuals, multitarget drug combinations
  • 2016: Added pathway cross-links for targets and drugs
  • 2014: Introduced biomarkers and drug scaffolds
  • 2012: Added target validation information and QSAR models
  • 2010: Included clinical trial drugs and similarity search

Applications and Impact

TTD data has been widely adopted for:

  • Drug Repurposing: Tools like LigAdvisor and DrugRep utilize TTD data
  • Target Discovery: Servers like CoVex and DeepCancerMap leverage TTD information
  • Adverse Drug Reaction Prediction: Systems like MEDICASCY and H-RACS use TTD data
  • Scientific Research: Hundreds of studies use TTD for genetic variant-disease associations, molecular characteristics of infections, target variability, and antifungal therapy discovery

Technical Infrastructure

TTD is maintained by the College of Pharmaceutical Sciences at Zhejiang University (China) in collaboration with the Department of Pharmacy at the National University of Singapore. The database is freely accessible without login requirements at https://idrblab.org/ttd/ and supports research and educational purposes.

Data Quality and Curation

Target and drug data in TTD undergo rigorous validation:

  • Approved drugs collected from authoritative FDA publications
  • Clinical trial drugs sourced from ClinicalTrials.gov, PhRMA reports, and company pipelines
  • Preclinical/patented drugs extracted from company reports and patent databases
  • Target status determined by highest drug development status
  • Target validation requires demonstrated functional roles in disease and drug modulation capability

Funding and Support

TTD development is supported by:

  • Natural Science Foundation of Zhejiang Province
  • Alibaba-Zhejiang University Joint Research Center of Future Digital Healthcare
  • Alibaba Cloud
  • Information Technology Center of Zhejiang University

Future Directions

TTD continues to expand its coverage of druggability characteristics and aims to facilitate the exploration of novel targets and discovery of new therapeutics. Future updates will focus on:

  • Integration of additional single-cell expression data
  • Expanded coverage of drug-target-disease relationships
  • Enhanced computational tools for druggability assessment
  • Improved cross-referencing with other biomedical databases

Citation

When using TTD, please cite:

Zhou Y, Zhang YT, Zhao DH, Yu XY, Shen XY, Zhou Y, Wang SS, Qiu YQ, Chen YZ, Zhu F. TTD: Therapeutic Target Database describing target druggability information. Nucleic Acids Research. 2024; 52(D1):D1465-D1477. doi:10.1093/nar/gkad751. PMID: 37713619.

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Created: October 29, 2025 | Last modified: October 29, 2025