Senior Associate Scientist - Assay Development

Senior Associate Scientist Assay Development Group Build our future together: At Regeneron, we use science and innovation to develop life-changing medicines for people with serious diseases. Regeneron's Assay Development Group (ADG), located in Tarrytown, NY, is seeking a Sr Associate Scientist to join our team. In this role, you will develop/optimize and execute mass spectrometry-based methods to quantify and investigate biologics, siRNAs, and novel antibody conjugates; generate high-quality data; and communicate findings that advance programs across the pipeline. This position offers the opportunity to work cross-functionally in a fast-paced, science-driven environment, applying technical expertise, creativity, and sound scientific judgment to solve complex challenges and help deliver meaningful therapies to patients worldwide. When & where: Location: Tarrytown, NY Discover your role: Optimize, troubleshoot, and execute quantitative mass spectrometry assays for biomarkers, therapeutic proteins, peptides, siRNAs, antibody conjugates, small molecules, and linker-payloads. Perform hands-on laboratory work using HPLC/UHPLC, mass spectrometry, KingFisher-based purification or extraction, and related quantitation/characterization techniques. Analyze and interpret complex datasets; maintain accurate electronic laboratory notebook records; and present findings clearly to technical, departmental, leadership, and cross-functional audiences. Manage multiple assays and projects concurrently and evaluate emerging technologies and assay formats. Maintain GLP-compliant laboratory practices and documentation for assay validations in accordance with FDA regulations and company SOPs. Collaborate within Bioanalytical Sciences, across Regeneron, and with CROs to troubleshoot challenges, align priorities, and support program execution. This role requires: A Bachelor's or Master's degree in Biophysics, Biochemistry, Chemistry, Engineering, or a related field, with at least 3 to 6 years of relevant industry experience appropriate to level. Ability to independently design experiments, analyze and interpret data, draw sound conclusions, and communicate findings to technical and cross-functional audiences. Hands on experience in operating and troubleshooting HPLC/UHPLC and mass spectrometry instrumentation (QQQ, Q-TOF and Orbitrap). Strong initiative, scientific curiosity, organization, and ability to prioritize multiple projects with minimal supervision in a collaborative environment. Excellent oral and written communication skills and a commitment to timely, compliant laboratory documentation. Preferred: Experience developing and executing quantitative mass spectrometry assays to support PK, PD, biomarker bioanalysis for large molecule therapeutic modalities. Preferred: Experience with KingFisher systems, high-throughput extraction, and other related automated sample preparation platforms. Experience in samples preparation for immunoaffinity capture, SPE and other fit-for-purpose bioanalytical approaches in different biological matrices. Preferred: Experience in developing novel bioanalytical assay platforms or introducing new assay formats and emerging technologies. Preferred: Understanding of protein/antibody structure-function relationships and PK/PD principles. Preferred: Biopharmaceutical industry experience, including collaboration with cross-functional teams and external partners such as CROs. Preferred: Prior experience in bioanalytical (regulated) assay execution and able to work collaboratively with a team mindset. 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,