Senior Principal Scientist, Bispecifics & Antibody Engineering

Build our future together: At Regeneron, we use science and innovation to develop life-changing medicines for people with serious diseases. We are seeking a Senior Principal Scientist to lead a small team within our Bispecific Antibodies group, using structural insight to design, engineer, and optimize next-generation bispecific and multispecific antibody therapeutics. In this role, you will integrate structural data with AI/ML-enabled design and high-throughput, automated experimental validation, co-championing programs with biology leads from concept to IND. This position offers the opportunity to contribute to a fast-growing, science-driven organization making a meaningful difference to patients worldwide. When & where: • Location: Tarrytown, NY • Work model/flexibility: Onsite Discover your role: • Set molecular design strategy for bispecific and multispecific antibodies based on target biology, structure, and mechanism of action • Lead structure-guided design of novel formats, including binding-arm selection, epitope and geometry optimization, and chain pairing, using tools such as AlphaFold, Rosetta, MOE, and PyMOL • Drive protein engineering campaigns that integrate AI/ML and in silico design into iterative design-build-test-learn cycles with computational partners • Oversee high-throughput construct generation, expression, purification, biophysical characterization, and cell-based functional assays to rank molecules on activity and developability • Build curated engineering datasets and design rules that strengthen the bispecific platform across oncology, immunology, and infectious disease • Lead, mentor, and develop a team of scientists, partnering with internal and external groups to advance the pipeline • Apply structural biology to solve hard antibody and protein engineering problems, combining experimental data with computational and AI/ML-driven design • Lead multiple projects in parallel with strong organization and flexibility, communicating structural insights clearly to non-specialist audiences This role requires: • Ph.D. in Structural Biology, Biochemistry, Biophysics, Protein Engineering, Computational Biology, Immunology, or a related field • 8+ years of post-Ph.D. experience, including at least 5 years in the biotech/pharmaceutical industry • At least 2 years of direct people management experience with a record of success developing scientists • A record of innovation and research accomplishments in antibody or protein therapeutic engineering (publications, patents, or programs advanced into development) • Experience engineering bispecific or multispecific antibody formats, with deep hands-on expertise in molecular cloning, protein expression, purification, and biochemical/biophysical characterization • Experience with mammalian cell culture and cell-based assay development • Preferred: experience applying computational design and AI/ML tools to protein engineering, and with automated or high-throughput protein engineering workflows Does this sound like you? Apply now to take your first step towards living the Regeneron Way! We are committed to building a workplace with an inclusive culture. Regeneron is an equal opportunity employer and all  qualified applicants will receive consideration for employment without regard to race, color, religion or belief (or lack thereof), sex, sexual orientation, gender identity or expression, gender reassignment, marital or civil partnership status, civil status, pregnancy or parental status, age, disability, nationality, citizenship status, ethnic or national origin, membership of the Traveler community, familial status, genetic information, military or veteran status, or any other characteristic protected under applicable law. Where required, we will p