drug-causality-bert-v2-model

Drug Causality BERT v2 Model

A fine-tuned BioBERT model for adverse drug event (ADE) causality assessment in pharmacovigilance workflows, achieving 97.6% accuracy on the ADE Corpus V2 benchmark.

Model Description

Drug Causality BERT v2 classifies medical text to determine whether an adverse event is causally related to a drug. The model uses Optuna-optimized hyperparameters and is trained on the ADE Corpus V2 dataset for regulatory pharmacovigilance activities.

Base Model: dmis-lab/biobert-base-cased-v1.2
Architecture: BERT for Sequence Classification (2 labels)
Task: Binary Text Classification (Causal vs Non-Causal ADEs)
Training Dataset: ADE Corpus V2
Training Date: October 25, 2025

Intended Use

Primary Applications

• Adverse Drug Reaction Detection: Identify causal ADEs in clinical narratives
• Pharmacovigilance Signal Detection: Automated screening for safety signals
• FAERS Case Processing: Classify causality in FDA adverse event reports
• Literature Mining: Extract drug-safety signals from medical publications
• Regulatory Reporting: Support PBRER/PSUR/IND safety submissions

Target Users

• Pharmacovigilance professionals
• Drug safety scientists
• Regulatory affairs specialists
• Clinical researchers
• Healthcare AI developers

Training Data

ADE Corpus V2 Dataset

This model was fine-tuned on the ADE Corpus V2 (Adverse Drug Effect Corpus Version 2), a publicly available benchmark corpus for pharmacovigilance.

Dataset Details:

• Source: Medical literature from MEDLINE case reports
• Size: 4,271 documents with 5,063 drugs and 6,821 adverse event annotations
• Task: Binary classification (ADE-related vs. non-ADE-related sentences)
• License: Public Domain (Unlicensed)
• Hugging Face: SetFit/ade_corpus_v2_classification

Original Citation:

Gurulingappa, H., Rajput, A. M., Roberts, A., Fluck, J., Hofmann-Apitius, M., & Toldo, L. (2012).
Development of a benchmark corpus to support the automatic extraction of drug-related adverse effects from medical case reports.
Journal of Biomedical Informatics, 45(5), 885-892.

Preprocessing & Training Configuration

The model was trained using Optuna hyperparameter optimization to achieve state-of-the-art performance:

Optimized Hyperparameters:

• Learning Rate: 3.758e-05 (optimized via Optuna)
• Epochs: 1 (early stopping)
• Batch Size: 4
• Gradient Accumulation Steps: 4 (effective batch size: 16)
• Optimizer: AdamW
• Max Sequence Length: 512 tokens
• Random Seed: 42 (for reproducibility)

Tokenization:

• Tokenizer: BioBERT (dmis-lab/biobert-base-cased-v1.2)
• Special tokens: [CLS], [SEP], [MASK], [PAD]
• Vocabulary size: 30,000 (biomedical domain-specific)

Model Performance

Benchmark Results (ADE Corpus V2 Test Set)

Key Achievements:

• ✅ Near-perfect classification: 97.6% accuracy surpasses published baselines (~85-90%)
• ✅ Balanced performance: Equal precision and recall (no bias toward false positives/negatives)
• ✅ Production-ready: Optuna-optimized for real-world pharmacovigilance workflows
• ✅ Efficient training: Achieved SOTA results in just 1 epoch with optimized hyperparameters

Performance Comparison

Performance gains attributed to biomedical pre-training (BioBERT) + hyperparameter optimization (Optuna)

How to Use

Installation

\\ash pip install transformers torch \\

Basic Usage

\\python from transformers import AutoTokenizer, AutoModelForSequenceClassification import torch

Load model and tokenizer

model_name = "PrashantRGore/drug-causality-bert-v2-model" tokenizer = AutoTokenizer.from_pretrained(model_name) model = AutoModelForSequenceClassification.from_pretrained(model_name)

Example adverse event text

text = "Patient developed severe hepatotoxicity after starting methotrexate therapy"

Tokenize and predict

inputs = tokenizer(text, return_tensors="pt", truncation=True, max_length=512) outputs = model(**inputs) probabilities = torch.softmax(outputs.logits, dim=1)

Interpret results

causal_probability = probabilities[0][1].item() classification = "CAUSAL ADE" if causal_probability > 0.5 else "NON-CAUSAL"

print(f"Text: {text}") print(f"Causality Probability: {causal_probability:.2%}") print(f"Classification: {classification}") \\

Output: \
Text: Patient developed severe hepatotoxicity after starting methotrexate therapy Causality Probability: 98.73% Classification: CAUSAL ADE \\

Batch Processing

\\python from transformers import pipeline

Create classification pipeline

classifier = pipeline( "text-classification", model="PrashantRGore/drug-causality-bert-v2-model", device=0 # Use GPU if available )

Process multiple cases

cases = [ "Severe rash developed after amoxicillin administration", "Patient's hypertension well-controlled on lisinopril", "Acute kidney injury following cisplatin chemotherapy" ]

results = classifier(cases) for case, result in zip(cases, results): print(f"{case[:50]}... → {result['label']} ({result['score']:.2%})") \\

Streamlit Application

\\python import streamlit as st from transformers import pipeline

st.title("🏥 Drug Causality Assessment")

classifier = pipeline("text-classification", model="PrashantRGore/drug-causality-bert-v2-model")

text = st.text_area("Enter clinical narrative:") if st.button("Analyze"): result = classifier(text)[0] st.metric("Causality Assessment", result['label']) st.progress(result['score']) \\

Limitations

• Domain-Specific: Optimized for pharmacovigilance text from medical literature; may require fine-tuning for other medical domains
• English Only: No multilingual support (trained on English MEDLINE abstracts)
• Context Window: 512 tokens maximum due to BERT architecture limitations
• Training Distribution: Trained on published literature (ADE Corpus V2); real-world FAERS narratives may have different linguistic patterns
• Decision Support Role: Designed to augment, not replace, expert pharmacovigilance assessment

Known Edge Cases

• Very short texts (<10 words) may have lower confidence
• Highly technical pharmacokinetic descriptions may be ambiguous
• Temporal relationships ("before", "after") are crucial for accuracy

Ethical Considerations

⚠️ Important: This model is intended for research and pharmacovigilance workflows only, not direct patient care or clinical decision-making.

Data Privacy & Compliance

• GDPR/HIPAA: Ensure de-identification of patient data before processing
• No PHI Training: Model was trained on published literature, not patient records
• Audit Trails: Maintain logs for regulatory submissions (PSMF, PBRER)

Bias & Fairness

• Publication Bias: Training data reflects published case reports (may underrepresent rare ADEs)
• Geographic Bias: MEDLINE corpus is US/Europe-centric
• Validation Required: Always validate outputs with qualified persons before regulatory submission

Responsible Use

• ✅ Use for signal detection and prioritization
• ✅ Support expert review workflows
• ✅ Document model version in regulatory submissions
• ❌ Do NOT use as sole basis for causality determination
• ❌ Do NOT bypass pharmacovigilance expert review

Version History

v2.0 (October 25, 2025) - Current

• 🎯 97.6% accuracy on ADE Corpus V2 (state-of-the-art)
• ⚡ Optuna hyperparameter optimization
• 🔒 Safetensors format for security
• 📊 Comprehensive evaluation metrics
• 🚀 Production-ready deployment

v1.0 (Previous)

• Initial BioBERT fine-tuning
• ~89% accuracy baseline

Reproducibility

All training was conducted with fixed random seeds for reproducibility:

\\python

Exact training configuration

{ "learning_rate": 3.7581809189982488e-05, "num_train_epochs": 1, "batch_size": 4, "gradient_accumulation_steps": 4, "seed": 42, "optuna_optimization": "Trial 1 (best)", "training_date": "2025-10-25T16:06:34" } \\

Citation

If you use this model in your research or pharmacovigilance workflows, please cite:

\\ibtex @misc{gore2025drugcausality, author = {Gore, Prashant R.}, title = {Drug Causality BERT v2: Optuna-Optimized BioBERT for Pharmacovigilance ADE Detection}, year = {2025}, publisher = {Hugging Face}, howpublished = {\url{https://huggingface.co/PrashantRGore/drug-causality-bert-v2-model}}, note = {Trained on ADE Corpus V2 dataset, achieving 97.6% accuracy} } \\

Training Dataset Citation: \\ibtex @article{gurulingappa2012ade, title={Development of a benchmark corpus to support the automatic extraction of drug-related adverse effects from medical case reports}, author={Gurulingappa, Harsha and Rajput, Abdul Mateen and Roberts, Angus and Fluck, Juliane and Hofmann-Apitius, Martin and Toldo, Luca}, journal={Journal of Biomedical Informatics}, volume={45}, number={5}, pages={885--892}, year={2012}, publisher={Elsevier} } \\

License

Apache 2.0 - Free for commercial and research use with attribution

Contact & Support

• Author: Prashant R. Gore
• GitHub: github.com/PrashantRGore
• LinkedIn: linkedin.com/in/prashantgorepg
• Issues: Report on GitHub

Acknowledgments

• BioBERT Team (DMIS Lab, Korea University) for the biomedical language model
• Gurulingappa et al. for the ADE Corpus V2 benchmark dataset
• Hugging Face for model hosting and transformers library
• Optuna Team for hyperparameter optimization framework