This project provides a Python script to analyze clinical trial data from ClinicalTrials.gov, specifically focusing on trials with a status of TERMINATED. For each terminated trial, the script fetches the "Why Stopped" reason from the ClinicalTrials.gov API, helping researchers and analysts better understand the causes of early trial termination.
WHY is this useful: The CSV export from Clinicaltrials.gov provides the "Trial Status" info. We can know if a trial is TERMINATED. However, the reason for termination is available in the posting but not in the extract. Hence, this code
I have used the same input file as in my other repositories.
Search query at CTG: https://clinicaltrials.gov/search?cond=Obesity&aggFilters=phase:3,status:rec Data retrieved on: 3 Jul 2025
This code pulled the Trial Termination reason for 140 trials in 57 seconds!
- Filters terminated studies from your dataset.
- Automates API calls to ClinicalTrials.gov for each terminated trial.
- Appends the "Why Stopped" reason to your DataFrame.
- Exports the results to an Excel file for further analysis.
Make sure you have the following Python libraries installed:
pandastqdmrequests
You can install them via pip:
pip install pandas tqdm requests
- Input: The script reads a CSV file containing clinical trial data.
- Filtering: It selects only the trials with a status of
TERMINATED. - API Query: For each terminated trial, it queries ClinicalTrials.gov to retrieve the "Why Stopped" reason.
- Output: The script prints a summary and saves the results as
Terminated trials.xlsx.
- Place your clinical trials CSV file in the project directory. Update the CSV file path in the script to match your file location: df = pd.read_csv('/path/to/your/input.csv')
- Update the script with the correct path to your CSV file.
- Run the script:
python terminated_trials_analysis.py
- After execution, check the output Excel file (
Terminated trials.xlsx) for results.
| NCT Number | Study Status | Why Stopped |
|---|---|---|
| NCT01977417 | TERMINATED | No Funding |
| NCT03991299 | TERMINATED | Sponsor Decision. |
- Ensure your CSV contains columns named "Study Status" and "NCT Number". Here the file used is a direct download from Clinicaltrials.gov and hence the column names. Ensure to use the same column names or adjust the reference in the code to NCT IDs as needed.
- API calls are limited by network speed and ClinicalTrials.gov rate limits.
This project is open source and available under the MIT License.
Contributions, suggestions, and improvements are welcome! Please open an issue or submit a pull request.
Happy analyzing!