Senior Principal/Principal Scientist – NGS & Molecular Assays (Cell & Gene Therapy)

About the position

Legend Biotech is seeking a Senior Principal/Principal Scientist – NGS & Molecular Assays (Cell & Gene Therapy) as part of the Bioanalytic Sciences team based in Somerset, NJ. We are seeking an experienced and highly motivated Bioanalytical Lead to develop and oversee molecular and NGS-based assays supporting preclinical IND-enabling through clinical-stage cell and gene therapy programs. This role will focus on autologous and allogeneic CAR-T, NK, γδT, and in vivo CAR-T gene editing therapies. The ideal candidate will have expertise in NGS, gene editing analysis (on/off-target), qPCR/ddPCR, and viral vector integration site analysis. This role involves designing and executing cutting-edge sequencing experiments, leading data analysis efforts, managing external vendors, and ensuring regulatory compliance.

Responsibilities

• Lead and execute NGS-based assays for gene editing and cell therapy applications, including Guide-seq, RhAMP-seq, PEM-seq, UDiTas related to on/off-target gene editing analysis.
• LVV/RVV integration analysis for lentiviral and retroviral vector insertion site profiling.
• TCR-seq and BCR-seq to assess TCR/BCR clonality in engineered cell therapies.
• Critically review and evaluate on/off-target gene editing analysis reports from internal teams and CROs.
• Design and execute single-cell RNA sequencing (scRNA-seq) experiments using patient-derived cells.
• Develop and validate qPCR/ddPCR assays for CAR transgene quantification and vector copy number analysis.
• Work with cross-functional teams to address key efficacy, safety, and product integrity questions regarding gene-modified cell therapies.
• Lead bioinformatics analysis of sequencing data, including single-cell RNA-seq, TCR-seq, BCR-seq, and off-target gene editing analysis.
• Ensure data quality control and interpretation using industry-standard bioinformatics tools and pipelines.
• Collaborate with computational biology teams to develop and optimize data analysis pipelines for NGS-based bioanalytical assays.
• Work with CROs for sample submission, assay development, validation, and data transfer.
• Ensure compliance with quality and regulatory requirements for outsourced bioanalytical testing.
• Troubleshoot and resolve technical and compliance-related issues with vendors.
• Maintain up-to-date written documentation of completed experiments in an electronic lab notebook.
• Ensure bioanalytical assays align with global regulatory guidelines (FDA, EMA, ICH) for gene editing and cell therapy products.
• Support regulatory submissions (IND, BLA) by providing bioanalytical data and justifications for assay selection and validation strategies.

Requirements

• Expertise in NGS techniques including single-cell RNA sequencing (scRNA-seq), library preparation, sequencing platforms, and data analysis.
• Hands-on experience in gene editing tools (CRISPR-based) and genetic modification of human primary cells or cell lines.
• Experience in designing and executing on- and off-target analysis assays, including Guide-seq, RhAMP-seq, PEM-seq, UDiTas.
• Knowledge of LVV/RVV integration analysis and immune repertoire sequencing (TCR-seq, BCR-seq).
• Experience with qPCR/ddPCR assays for CAR transgene quantification and genomic characterization.
• Strong understanding of immune cell isolation, purification, and molecular biology techniques relevant to NGS.
• Proficiency in bioinformatics tools for NGS data analysis, quality control, and interpretation.
• Familiarity with genome editing readouts and computational tools for off-target evaluation.
• Experience managing CROs and external vendors for bioanalytical assay development and validation.
• Working knowledge of GLP, GCP, and regulatory expectations for gene and cell therapy bioanalytical assays.
• Prior involvement in regulatory submissions (IND, BLA) and regulatory agency interactions.
• Ability to work cross-functionally with Research, Translational Science, Process Development, and Clinical teams.
• Excellent communication and problem-solving skills in a fast-paced, collaborative environment.