> Markdown version of [/jobs/ext/1949611-principal-scientist-data-science](https://www.wearedevelopers.com/jobs/ext/1949611-principal-scientist-data-science). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Principal Scientist Data Science - **Company:** Johnson & Johnson, S.a. - **Location:** Barcelona, Spain - **Salary:** €117,000.0 - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Health Informatics, Clinical Trial Management Systems, Program Optimization, Computer Literacy, Continuous Integration, Data Visualization, DevOps, Information Extraction, Python (Programming Language), Linear Programming, Machine Learning, Natural Language Processing, Operational Data Store, SQL Databases, Reinforcement Learning, Electrical and Computer Engineering, Large Language Models, Electronic Medical Records, Gitlab, Git, Scikit Learn, Information Technology, Optimization Algorithms, Xgboost, Machine Learning Operations, Jenkins, Programming Languages - **Published:** August 6, 2026 - **Apply:** https://www.jobleads.com/es/job/ee1ffcbf94268fc7efeab62e2537b50ab ## About the Role * A Ph.D. degree in a quantitative discipline (e.g., computer science, electrical and computer engineering, biostatistics, health economics, biomedical informatics, applied mathematics, or similar), * 5+ years of industry experience delivering on data science projects using ML predictive modeling, multi-objective optimization, natural language processing, and GenAI. * Hands-on experience with multi-modal ML predictive modeling and stochastic simulations for time-series forecasting. * Experience building multi-objective optimization engines to navigate complex trade-offs using evolutionary algorithms, reinforcement learning, or mixed-integer linear programming. * Experience with GenAI and clinical LLMs for document parsing and clinical concept disambiguation and harmonization. * Proficient in MLOps practices and tools (MLflow, Kedro); Git usage, CI/CD stacks (Jenkins, GitLab) DevOps tools. * Proficiency with programming languages Python and SQL, * Experience with python LLM tools (e.g., DSPy, LangChain), optimization tools (e.g., pymoo) and ML tools (e.g., Scikit-learn, XGBoost, Optuna, PyMc), * Demonstrated experience and familiarity with clinical operational data, real world data, electronic health records and claims, and financial data., * Prior experience in a data science AI/ML role in healthcare, MedTech, and pharmaceutical industries. * Hand-on experience utilizing clinical trial protocols, registry, cost data, CTMS, EDC and/or EHR to build ML models for estimating operational outcomes or RWE outcomes., * Advanced Analytics, Coaching, Critical Thinking, Data Analysis, Data Privacy Standards, Data Quality, Data Reporting, Data Savvy, Data Science, Data Visualization, Digital Fluency, Econometric Models, Organizing, Process Improvements, Strategic Thinking, Technical Credibility, Workflow Analysis ## Description J&J Innovative Medicine - Data, Data Science, and AI - Global Development (DDSAI GD) is recruiting a Principal Scientist. The ideal candidate will leverage, adapt, and extend machine learning (ML), optimization techniques, and GenAI techniques to create computational pipelines supporting global clinical operations including enrollment forecasting, cost estimation and optimization, and country/site selection., * Conceive, develop, and implement ML, multi-objective optimization, GenAI solutions to support clinical trial operations. * Leverage operational, RWD, and cost data to build ML predictive models and optimization engines to 1) predict outcomes of interest, 2) highlight tradeoffs between competing objectives, 3) recommend optimal operational scenarios, and 4) generate actionable insights, enabling early intervention and risk management. * Adapt large language models (LLMs) for tailored information extraction and to create solutions including conducting comparative analytics on clinical trial protocols and trial similarity assessment, * clinical trial data harmonization and standardization, * schedule of activity optimization, and * eligibility criteria evaluation, * Stochastic enrollment simulations to forecast operational and patient journey outcomes including enrollment and study completion. * Clearly articulate highly technical methods and results to diverse audiences and partners to drive decision-making. * Coaches and trains junior colleagues in techniques, processes, and responsibilities. ## Related Videos - [WeAreDevelopers LIVE - Modern DevOps for IoT Devices and More](https://www.wearedevelopers.com/videos/1805-wearedevelopers-live-modern-devops-for-iot-devices-and-more) - [Data Science in Retail](https://www.wearedevelopers.com/videos/586-data-science-in-retail) - [How a Small Team Shrank a Microsoft Monorepo by 94%](https://www.wearedevelopers.com/videos/1236-how-a-small-team-shrank-a-microsoft-monorepo-by-94) - [From DevOps to Scaled DevOps: How We’re Rebuilding Continuous Delivery as a Platform](https://www.wearedevelopers.com/videos/100018-from-devops-to-scaled-devops-how-we-re-rebuilding-continuous-delivery-as-a-platform) - [Blueprints for Success: Steering a Global Data & AI Architecture](https://www.wearedevelopers.com/videos/1577-blueprints-for-success-steering-a-global-data-ai-architecture) - [Git for Code Reviews](https://www.wearedevelopers.com/videos/429-git-for-code-reviews) ## Related Articles - [Coffee with Developers - Maria Apazoglou - Making AI understandable for all in production](https://www.wearedevelopers.com/magazine/475-coffee-with-developers-maria-apazoglou-making-ai-understandable-for-all-in-production) - [MLOps – What’s the deal behind it?](https://www.wearedevelopers.com/magazine/125-mlops-what-s-the-deal-behind-it) - [How to Become an AI Engineer](https://www.wearedevelopers.com/magazine/331-how-to-become-an-ai-engineer) - [Graph and AI Trends 2026: Why Is AI Running but Not Yet Delivering?](https://www.wearedevelopers.com/magazine/680-graph-and-ai-trends-2026-why-is-ai-running-but-not-yet-delivering) - [What Industries Outside of AI Are Hiring The Most AI Experts?](https://www.wearedevelopers.com/magazine/98-what-industries-outside-of-ai-are-hiring-the-most-ai-experts) - [MLOps And AI Driven Development](https://www.wearedevelopers.com/magazine/82-mlops-and-ai-driven-development)