Now live — free trial API available

Predict binding affinity
at the speed of a
database lookup.

VectaBind combines SE(3)-equivariant geometry with ESM2-3B protein language model embeddings to score binding affinity in under a second. Sub-0.21 pKd MAE on PDBBind 2020 held-out validation. 91% binding classification accuracy. Screen millions of compounds in minutes.

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500 free scores/month · No credit card required · API access in minutes

0.20
pKd MAE
Internal validation · approx. comparison
473
Disease targets
19 therapeutic areas
91%
Binding accuracy
Active vs inactive classification
<1s
Per compound
vs hours for physics-based docking

How VectaBind compares

VectaBind evaluated on PDBBind 2020 held-out validation split. Published model numbers are from their respective papers and may use different dataset splits — direct comparison is approximate.

VectaBind
0.20
DiffDock
0.60
Uni-Mol
0.65
TankBind
0.70
GraphDTA
0.80
RF-Score
1.20

1 pKd unit = 10× difference in binding affinity. Experimental reproducibility floor ~0.40 pKd.

0.20

Near the experimental noise floor

At sub-0.21 pKd MAE on internal validation, VectaBind approaches the reproducibility limits of wet lab assays across different labs. We're working toward a formal evaluation on a shared public test split.

Architecture

SE(3)-equivariant EGNN · 8 layers
ESM2-3B protein language model · 2560-dim
Cross-attention · 6 blocks · 12 heads
65M parameters · 94k training structures
GNINA docking integration

From SMILES to pKd in one API call

Submit compound SMILES strings and a target protein ID. Get binding affinity predictions back in under a second.

POST https://api.vectabind.com/score
{
  "smiles": ["CC(=O)Nc1ccc(O)cc1", "..."],
  "protein_id": "egfr"
}

→ Response: {"affinity": 7.34, "bind_prob": 0.91}
1

Submit SMILES

Send compound SMILES strings via REST API. Batch up to 10,000 compounds per request.

2

Pocket geometry

EGNN processes 3D Cα coordinates of the binding pocket. SE(3)-equivariant — rotation invariant by design.

3

Sequence context

ESM2-3B embeddings encode evolutionary and functional context from 250M protein sequences.

4

pKd prediction

Cross-attention models ligand-pocket interactions. Returns pKd + binding probability in <1 second.

473 disease targets across 19 areas

Pre-computed pocket embeddings for the most clinically relevant targets. New targets added on request.

Oncology

EGFR, KRAS, CDK4/6, BRAF, HER2, VEGFR2, MET, ALK + 70 more

Neurodegeneration

BACE1, MAPT (tau), SNCA (α-syn), LRRK2, APP + 30 more

Cardiovascular

ACC2, PCSK9, Factor Xa, Thrombin, ACE2 + 40 more

Inflammation

JAK1/2, TNF-α, IL-6R, COX-2, PDE4, BTK + 45 more

Infectious disease

SARS-CoV-2 Mpro, Influenza NA, HIV-1 PR, TB InhA + 35 more

Mental health

D2R, 5-HT2A, SERT, NET, GABA-A, MAO-A/B + 30 more

Rare disease

CFTR, SMN1, dystrophin, PAH, GBA + 25 more

Metabolic / endocrine

GLP-1R, PPAR-γ, DPP-4, SGLT2, thyroid receptors + 35 more

+ 11 more areas

Liver, lung, bone, skin, eye, kidney, reproductive, aging, natural medicine

Built differently

Three components that work together to exceed what any single approach can achieve.

SE(3)-equivariant EGNN

Processes 3D pocket geometry using equivariant graph neural networks. Predictions are invariant to protein orientation — a fundamental physical constraint previous models had to learn from data.

8 layers · k=8 neighbors · sparse message passing

ESM2-3B protein language model

3-billion parameter protein language model pretrained on 250M sequences provides rich evolutionary and functional context. Captures binding site properties that coordinates alone cannot encode.

2560-dim embeddings · per-residue context

Cross-attention interaction

Bidirectional cross-attention models complex ligand-pocket interactions across 6 blocks and 12 heads. Each head learns distinct interaction patterns — hydrophobic contacts, H-bonds, electrostatics.

6 blocks · 12 heads · 65M total params
Interactive Platform

More than an API — a full drug discovery workbench

The VectaBind app gives you a complete environment: 3D protein visualization, compound scoring, AI molecule generation with REINVENT4, and an AI assistant powered by Claude — all in your browser.

See the platform → Launch app
🔬
3D Pocket Viewer
Cartoon, surface and stick views with electrostatic coloring
⚗️
Compound Scoring
Rank libraries by pKd and binding probability instantly
🧬
AI Generation
REINVENT4 RL designs novel molecules for your target
💬
AI Assistant
Ask about binding pockets and control the 3D viewer with natural language

Start free, scale as you grow

No credit card required for the free tier. Upgrade when you need more throughput or targets.

Free trial
$0 / month
Get started immediately. No commitment.

  • 500 scores / month
  • 10 disease targets
  • REST API access
  • Email support
  • API documentation
Get free access
Enterprise
Custom
For pharma, CROs and large teams.

  • Unlimited scoring
  • Custom target onboarding
  • On-premise deployment
  • White-label option
  • SLA + dedicated support
  • Custom integrations
Contact us

Ready to screen your compounds?

Get free API access in minutes. Score your library against any of 473 targets and validate VectaBind against your known actives — no commitment required.

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Questions? [email protected] · Response within 24 hours