Senior Scientist I, Bioassay at Exelixis in Alameda, CA

Job description

SUMMARY/JOB PURPOSE: The Senior Scientist I, Analytical Development, Biologics CMC will support CMC analytical development for biologic therapeutics by establishing and advancing phase-appropriate cell-based bioassay, potency, functional, and binding assay capabilities. This hands-on role will independently develop, optimize, qualify, transfer, and manage fit-for-purpose assays that reflect product mechanism of action and relevant critical quality attributes across ADCs, monoclonal antibodies, bispecifics, multispecifics, Fc-fusion proteins, VHH-Fc constructs, and other novel biologic modalities. The position exists to ensure scientifically rigorous, regulatory-relevant, cost-effective, and timely potency assay strategies through strong laboratory execution, technical ownership, and effective collaboration with Discovery, Translational Sciences, Process Development, Quality, Regulatory, CDMOs, CTLs, and external partners. ESSENTIAL DUTIES/RESPONSIBILITIES: Develop complex cell-based bioassays and potency assays from initial concept through optimization, qualification, and method transfer for biologic therapeutics. Perform hands-on mammalian cell culture, transient transfection, engineered cell model development, receptor-expression confirmation, and assay-ready cell support. Develop and troubleshoot functional bioassays, including reporter-gene, cytotoxicity, proliferation/inhibition, receptor blockade, ADCC/CDC, and immune-cell engagement assays. Apply flow cytometry, ELISA or plate-based binding assays, SPR/BLI, and other orthogonal methods to support assay development, comparability, and structure-function understanding. Evaluate assay performance, robustness, system suitability, relative potency, parallelism, and critical assay parameters to enable phase-appropriate method qualification and transfer. Author and review assay procedures, development reports, qualification or transfer documents, technical summaries, and CMC-relevant regulatory supporting materials. Collaborate with Discovery, Translational Sciences, Process Development, Quality, Regulatory, CDMOs, CTLs, and external partners to align assay strategy with program needs. Contribute to building internal bioassay capabilities, including cell culture workflows, flow cytometry practices, plate-reader methods, data analysis tools, and critical reagent management. SUPERVISORY RESPONSIBILITIES: No direct people management responsibility is required. The incumbent may provide technical guidance, training, and work direction to junior scientists, research associates, consultants, CDMOs, CTLs, and other external partners. EDUCATION/EXPERIENCE/KNOWLEDGE & SKILLS: Education: Ph.D. in cell biology, immunology, molecular biology, biochemistry, bioengineering, biophysics, pharmaceutical sciences, analytical sciences, or a related life sciences discipline with relevant industry experience; or, Master’s degree in cell biology, immunology, molecular biology, biochemistry, bioengineering, biophysics, pharmaceutical sciences, analytical sciences, or a related life sciences discipline with 5+ years of relevant industry experience; or, Bachelor’s degree in cell biology, immunology, molecular biology, biochemistry, bioengineering, biophysics, pharmaceutical sciences, analytical sciences, or a related life sciences discipline with 7+ years of relevant industry experience; or, Equivalent combination of education and experience. Experience: Hands-on experience developing complex cell-based bioassays or functional assays from concept through optimization, qualification, troubleshooting, documentation, and method transfer. Experience with mammalian cell culture, assay-ready cells, transient transfection or engineered cell models, flow cytometry, plate-based assays, and functional potency readouts is strongly preferred. Knowledge, Skills and Abilities: Advanced knowledge of cell-based bioassay and potency assay development for biologic therapeutics, including mammalian cell culture, flow cy