PhD Biostatistician & FDA Clinical Trial Expert

Specialties & Experience of this Expert Witness

Additional Information

Lei Li, PhD, is a biostatistician and former FDA CDRH statistical reviewer with extensive experience in regulatory statistics, Real-World Evidence (RWE), medical device submissions, and pharmaceutical development. At FDA, Dr. Li evaluated statistical components of 510(k) and PMA submissions, assessed safety and effectiveness evidence for medical devices, reviewed RWE and post-market studies, and advised on complex statistical issues for regulatory decision-making. His FDA work included evaluation of study design adequacy, endpoint justification, sample-size rationale, bias and confounding, missing data robustness, and interpretation of clinical performance metrics under regulatory standards. In industry, Dr. Li served as Statistical Project Leader at Sanofi and Principal Biostatistician at Edwards Lifesciences, supporting global clinical and regulatory programs across multiple therapeutic areas, including rare diseases, inflammatory diseases, vaccines, oncology, and cardiovascular medicine. He has designed and analyzed Phase I–III clinical trials, post-market surveillance studies, device performance evaluations, and observational RWE studies. Dr. Li has contributed to INDs, BLAs, 510(k) submissions, PMAs, protocol development, SAP drafting, interim monitoring, and preparation for regulatory agency meetings. Dr. Li specializes in clinical trial methodology and advanced statistical inference. His areas of expertise include Bayesian and group sequential designs, adaptive and platform trial designs, blinded sample-size re-estimation, survival modeling, time-to-event analysis, longitudinal and mixed-effects modeling, multiplicity control, AE/SAE analysis, and extensive work with missing data (MAR, MNAR, sensitivity analyses, tipping point analyses). He is experienced in evaluating study integrity, randomization imbalance, protocol deviations, subgroup evaluations, and data quality issues relevant to litigation and regulatory review. Dr. Li provides expert consultation on: • Statistical causation and inference • Evaluation of study design flaws and bias • Reanalysis of clinical trial and RWE evidence • Medical device safety and performance statistics • Vaccine effectiveness and immunogenicity analysis • Statistical robustness and sensitivity analyses • Data integrity, protocol compliance, and error assessment • FDA regulatory expectations and evidence interpretation Dr. Li holds a PhD in Statistics from George Mason University and has published multiple peer-reviewed articles in biostatistics, statistical inference, robust estimation, divergence-based methods, sequential design, and clinical trial theory. His scholarly work includes methodological research on mixture models, robust inference techniques, and advanced statistical algorithms, providing a rigorous scientific foundation for his expert evaluations. He has extensive experience presenting complex statistical concepts to attorneys, clinicians, and regulators, and is skilled in preparing clear expert reports, explaining statistical issues to non-technical audiences, and supporting litigation through statistical review, expert testimony, and data-driven evaluation of causation. Dr. Li also works extensively in artificial intelligence and machine-learning model validation, including algorithmic fairness assessment, model robustness evaluation, and validation of clinical prediction models for regulatory and legal use cases. His combined background in FDA regulatory statistics, clinical trial methodology, medical devices, and AI model validation makes him uniquely qualified to support litigation, regulatory review, and statistical expert witness engagements.