Senior Scientist, Process Development

At Gilead, we’re creating a healthier world for all people. For more than 35 years, we’ve tackled diseases such as HIV, viral hepatitis, COVID-19 and cancer – working relentlessly to develop therapies that help improve lives and to ensure access to these therapies across the globe. We continue to fight against the world’s biggest health challenges, and our mission requires collaboration, determination and a relentless drive to make a difference. Every member of Gilead’s team plays a critical role in the discovery and development of life-changing scientific innovations. Our employees are our greatest asset as we work to achieve our bold ambitions, and we’re looking for the next wave of passionate and ambitious people ready to make a direct impact. We believe every employee deserves a great leader. People Leaders are the cornerstone to the employee experience at Gilead and Kite. As a people leader now or in the future, you are the key driver in evolving our culture and creating an environment where every employee feels included, developed and empowered to fulfil their aspirations. Join Gilead and help create possible, together. Job Description The Senior Scientist, Purification Process Development & Technology Transfer will provide scientific and technical leadership for the development, scale-up, characterization, technology transfer, and manufacturing implementation of biologics drug substance purification processes. This role spans the purification process from harvest through bulk drug substance, including harvest clarification, chromatography, virus inactivation, virus filtration, ultrafiltration/diafiltration, formulation, and drug substance final filtration. The successful candidate will combine strong hands-on purification expertise with demonstrated experience transferring drug substance processes to internal manufacturing sites and external partners or contract development and manufacturing organizations and supporting GMP manufacturing execution. Key Responsibilities Serve as the purification technical lead for assigned pivotal and commercial programs, providing scientific direction, identifying technical risks, and communicating recommendations, trade-offs, and mitigation strategies to project and functional teams. Lead drug substance technology-transfer workstreams to internal manufacturing sites and external partners or contract development and manufacturing organizations, including process scale-up, facility fit, manufacturing readiness, and transfer execution. Lead the development, optimization, scale-up, and characterization of robust, scalable, and manufacturable biologics purification processes. Provide hands-on technical leadership across harvest clarification, chromatography, virus inactivation, virus filtration, other filtration operations, ultrafiltration/diafiltration, formulation, and final filtration. Design, execute, and interpret process characterization and scale-down studies using appropriate scientific and statistical approaches, including Design of Experiments. Establish scientifically justified operating ranges and contribute to the development of integrated process control strategies. Develop project plans, coordinate technical activities, manage risks, and deliver purification work products in alignment with program objectives and timelines. Provide technical support during engineering, clinical, process performance qualification, and other GMP manufacturing campaigns, including on-site and person-in-plant support as needed. Lead or support troubleshooting, deviation investigations, root-cause assessments, and technical investigations related to process performance and GMP manufacturing. Author and review development reports, study protocols, process descriptions, technology-transfer documentation, standard operating procedures, manufacturing batch records, and CMC regulatory content. Collaborate across Process Development, Manufacturing and MSAT, Analytical Development, Formulation Development, Quality, Regulatory Affairs, Supply Chain, and other CMC functions. Mentor junior scientists and contribute to the advancement of purification technologies, platform processes, and organizational best practices. Travel as needed to support technology transfers and provide technical oversight at internal and external manufacturing facilities. Basic Qualifications PhD in Chemical Engineering, Biochemical Engineering, Bioengineering, Biochemistry, or a related scientific discipline with 2 or more years of relevant experience; MS in a relevant scientific or engineering discipline with 6 or more years of relevant experience; or BS in a relevant scientific or engineering discipline with 8 or more years of relevant experience. Preferred Qualifications Experience in biologics purification process development, characterization, scale-up, and GMP manufacturing implementation. Demonstrated experience leading drug substance technology transfers to internal manufacturing sites, external partners, or contract development and manufacturing organizations. Broad technical expertise in harvest clarification, chromatography, virus inactivation, virus filtration, ultrafiltration/diafiltration, formulation, and final filtration. Experience supporting engineering, clinical, process performance qualification, and commercial manufacturing campaigns, including batch-record review and on-site or person-in-plant support. Experience establishing and qualifying scale-down models and applying Design of Experiments and statistical analysis to define operating ranges and characterize process performance. Experience developing process control strategies and supporting process validation readiness. Experience authoring or contributing to CMC regulatory filings and responses to health authority questions. Demonstrated ability to identify and resolve complex technical risks using sound scientific judgment. Strong technical writing, communication, cross-functional collaboration, and project leadership skills. The salary range for this position is: $169,320.00 - $219,120.00. Gilead considers a variety of fact