Scientist II, Antibody Engineering

About Astellas

Astellas is a global life sciences company committed to turning innovative science into VALUE for patients. We provide transformative therapies in disease areas that include oncology, ophthalmology, urology, immunology and women's health. Through our research and development programs, we are pioneering new healthcare solutions for diseases with high unmet medical need. Learn more at

Astellas is a global life sciences company committed to turning innovative science into VALUE for patients. We provide transformative therapies in disease areas that include oncology, ophthalmology, urology, immunology and women's health. Through our research and development programs, we are pioneering new healthcare solutions for diseases with high unmet medical need. Learn more at

We're seeking passionate individuals who thrive in dynamic environments, embrace new ideas, and aren't afraid to take intelligent risks. People who act with unwavering integrity and are deeply committed to making a tangible impact.

This Scientist II role in the Antibody Engineering department will drive the discovery and development of next-generation biologics and immuno-oncology therapeutics in Oncology Research by integrating antibody engineering, structural biology, and AI-enabled protein design. The role will contribute to innovative therapeutic modalities including T-cell engagers (TCEs), ADCs, multispecific antibodies, and cytokine-based therapeutics to improve safety and efficacy for patients. Working closely with Cancer Biology, Translational Science, AI/ML and global Biologics Engineering organization in South San Francisco and Japan, this scientist role will lead / support research programs, advance platform technologies, and translate novel concepts into differentiated therapeutic candidates.

The position is expected to contribute scientific innovation, intellectual property generation, and technology development that enables future biologics discovery and development.

• Design, engineer, and characterize bispecific antibodies, T-cell engagers (TCEs), engineered cytokines, and other multifunctional biologics.
• Apply iterative design-make-test-learn cycles to biologics discovery, lead optimization, and candidate selection. Generate and interpret experimental data to guide project decisions.
• Partner with teams across Cancer Biology, Translational Science, AI/ML and global Biologics Engineering organization in South San Francisco and Japan to advance therapeutic candidates from discovery through preclinical development.
• Coordinate activities with CROs and external technology partners, including outsourced protein production, analytical characterization, and collaborative research efforts.
• Apply emerging antibody engineering, structural biology, and AI/ML technologies, including AI-enabled SaaS platforms and autonomous AI agents, to enhance biologics discovery and optimization.
• Analyze experimental and computational data, maintain accurate records in LIMS, ELN, and communicate findings to project teams, senior leadership, and external scientific audiences. Document workflows, contribute to technical reports, publications, invention disclosures, and patent applications, and present research at scientific conferences when appropriate.

• PhD with 2+ years of industry experience in antibody/protein engineering, structural biology, biophysics, and biochemistry, preferably within oncology and/or immuno-oncology drug discovery.
• Demonstrated expertise in antibody and protein design, including the application of AI/ML-enabled protein engineering approaches. Experience may include generative protein design, structure prediction, and optimization of antibodies/formats, TCEs, ADCs, cytokine-based therapeutics, using protein language models and structural modeling tools.
• Experience in antibody purification including chromatography methods such as protein A, Ni-NTA, HIC, IEX, SEC.
• Proficiency in molecular biology techniques, including DNA construct design, PCR, DNA purification, cloning, and plasmid engineering.
• Hands-on experience in antibody engineering platform development and implementation of biochemical and biophysical characterization assays, such as Octet/BLI, ELISA, FRET-based assays, CE-SDS.
• Demonstrated ability to independently design, execute, troubleshoot, and interpret experiments, including development and…