Downstream Scientist/Senior Associate Scientist

Legend Biotech is a global biotechnology company dedicated to treating, and one day curing, life-threatening diseases. Headquartered in Somerset, New Jersey, we are developing advanced cell therapies across a diverse array of technology platforms, including autologous and allogenic chimeric antigen receptor T-cell, T-cell receptor (TCR-T), and natural killer (NK) cell-based immunotherapy. From our three R&D sites around the world, we apply these innovative technologies to pursue the discovery of safe, efficacious and cutting-edge therapeutics for patients worldwide.

Legend Biotech entered into a global collaboration agreement with Janssen, one of the pharmaceutical companies of Johnson & Johnson, to jointly develop and commercialize ciltacabtagene autolecuel (cilta-cel). Our strategic partnership is designed to combine the strengths and expertise of both companies to advance the promise of an immunotherapy in the treatment of multiple myeloma.

Legend Biotech is seeking a Downstream Scientist/Senior Associate Scientist as part of the US R&D team based in Philadelphia, PA.

Role Overview

Legend Biotech is seeking a Senior Associate Scientist or Scientist to join the Vector Biology team in the department of R&D to support research-stage and early process development for lentiviral vector (LV) downstream workflows. This role will design and execute experiments to rapidly evaluate and optimize purification strategies from harvest through final filtration, enabling internal discovery programs and early translational activities. The ideal candidate is highly hands-on, experimental, and comfortable operating in an iterative R&D environment where speed, learning, and data quality matter.

Key Responsibilities

• Design and execute early-stage downstream process (DSP) experiments to explore purification concepts, identify bottlenecks, and establish fit-for-purpose viral vector downstream process approaches.
• Rapidly optimize the downstream operations including optimal harvest strategy, clarification, chromatography, concentration (TFF), final filtration and final formulation preparation.
• Perform routine viral vector purification runs (weekly or as program needs dictation) to generate material for internal research teams, assay development and preclinical enablement.
• Partner closely with the Upstream team to define handoffs, characterize feed streams, and align harvest timing/conditions with downstream performance.
• Collaborate with Analytical colleagues to select fit-for-purpose assay and interpret results to guide process decisions and next experiments.
• Independently plan, conduct, analyze, and present data, translating experimental outcomes into clear next steps and recommendations.
• Track timelines and deliverables for small-scale early PD work activities, communicating progress, risks and tradeoffs in a fast-moving R&D setting.
• Support early tech transfer readiness by capturing process learnings, rationale, and draft procedures as processes mature.
• Prioritize experiments based on learning value, program urgency, and material needs, balancing exploratory studies with routine production support.
• Recommend DSP path forward using data-driven tradeoffs.
• Escalate risks and propose mitigations when process performance, timelines, or resource needs could impact research deliverables. 

Requirements

• PhD in Biochemistry, virology, cell & gene therapy bioengineering or related field.
• MS with 3-4+ years or BS with 5-6+ years of relevant industry experience.
• Hands-on experience with viral vector downstream processing in a research and/or early process development environment, with a demonstrated ability to iterate quickly and translate learning into next step experiments.
• Demonstrated experience designing and executing lab- or PD-scale downstream workflows spanning harvest/clarification, chromatography, TFF and sterile filtration to generate material and internal research and early translational needs.
• Experience partnering with Upstream, Molecular Biology, and Analytical teams to align harvest timing, culture conditions, sampling plans, assay selection, and data interpretation to guide experimental direction.
• Track record of producing clear, decision-enabling data packages that support down-selection of downstream process options and inform early platform/process strategy.