Associate Scientist, Immunogenicity Assessment

About Xaira Therapeutics Xaira is an innovative biotech startup focused on leveraging AI to transform drug discovery and development. The company is leading the development of generative AI models to design protein and antibody therapeutics, enabling the creation of medicines against historically hard-to-drug molecular targets. It is also developing foundation models for biology and disease to enable better target elucidation and patient stratification. Collectively, these technologies aim to continually enable the identification of novel therapies and to improve success in drug development. Xaira is headquartered in the San Francisco Bay Area, Seattle, and London. About the Role We are seeking a Scientist to join our Immunogenicity team within Biology & Pharmacology to lead and execute immunogenicity risk assessment for de novo protein therapeutics. This role is central to our Immunogenicity Risk Assessment and Management framework, encompassing pre-clinical immunogenicity characterization, ADA assay development, and risk-tiering of novel biologic formats including VHH antibodies, minibinders, and T cell engager (TCE) bispecific antibodies. You will operate at the interface of translational science and assay development, partnering closely with discovery biology, process development, and clinical teams to ensure immunogenic risk is identified and managed across the development pipeline. About You The successful candidate is a hands-on immunogenicity scientist with a strong grasp of antibody biology, T and B cell immunology, and bioanalytical assay development. At this level, you independently design and execute experiments of significant scope and complexity — establishing experimental strategy, selecting appropriate methods, drawing conclusions, and defining next steps with minimal supervision. You are comfortable evaluating variable factors in complex datasets, exercising scientific judgment to interpret relationships and solve problems within defined frameworks, and knowing when to seek guidance on broader implications. You actively collaborate, share knowledge, and support peers across the immunogenicity and broader translational sciences team. You are comfortable contributing to cross-functional updates and have a track record of identifying opportunities for improvement and implementing changes within your personal scope. You thrive in fast-paced environments and bring a rigorous yet pragmatic approach to assay design, data interpretation, and risk communication. You are comfortable leveraging AI tools to accelerate experimental design, synthesize complex datasets, and surface actionable insights. Key Responsibilities Independently design and execute immunogenicity risk assessments including pre-existing ADA screening and T cell reactivity profiling. Develop and optimize ADA assay platforms (liquid-phase bridging MSD ECL); independently define cut points, validation strategies, and risk classification. Design and execute T cell activation assays with fresh and cryopreserved PBMCs; interpret MSD V-Plex cytokine readouts using appropriate metrics and recommend assay adjustments based on results. Leverage AI tools to support experiment design, data summarization, and interpretation of complex immunogenicity datasets; apply AI-assisted approaches to identify patterns across multi-donor and multi-analyte studies and generate hypothesis-driven insights. Align immunogenicity programs with EMA and FDA guidance; Assist in preparing risk summaries and data packages for IND-enabling and clinical support. Collaborate with discovery and process development teams to de-risk immunogenicity at candidate selection; share knowledge and support peers across functions. Identify and implement improvements to immunogenicity workflows within personal scope; contribute to our risk assessment framework evolution and internal best practices. Maintain rigorous records and SOPs; contribute to cross-functional updates and develop internal training materials and risk assessment guidance documents. Qualifications BS or M.S. (6+ years industry experience) in Immunology, Biochemistry, Bioengineering, or a closely related field; industrial biopharmaceutical experience strongly preferred. Proven expertise in ADA assay development and validation, including bridging immunoassay formats (MSD ECL, ELISA), with hands-on experience defining cut points, drug tolerance, and tiered confirmation strategies. Demonstrated experience with T cell reactivity assays using PBMCs; proficiency in cytokine multiplexing platforms (MSD V-Plex or equivalent) and interpretation of stimulation indices. Understanding of antigen presentation, T/B cell collaboration, and the molecular mechanisms driving ADA induction to endogenous proteins and biologic drugs. Familiarity with bispecific antibody formats, novel scaffold biologics (VHH, minibinders), or T cell engager modalities and their unique immunogenicity risk profiles. Proven track record of independent project ownership, cross-functional collaboration, and delivering scientific output in fast-paced discovery or development environments. Strong quantitative skills; experience designing composite risk metrics, managing multi-donor PBMC datasets, and applying statistical methods to immunogenicity data. Comfort using AI-assisted tools for scientific tasks including experiment design, literature synthesis, data summarization, and pattern recognition in complex immunogenicity datasets; openness to integrating emerging AI capabilities into day-to-day workflows. Dedicated to inclusive scientific leadership and maintaining a collaborative, respectful team environment. Compensation We offer a competitive compensation and benefits package, seeking to provide an open, flexible, and friendly work environment to empower employees and provide them with a platform to develop their long-term careers. A Summary of Benefits is available for all applicants. We offer a competitive package that includes base salary, bonus, and equity. The base pay range for this position is expected to be $101,000 - $126,000 annually; however, the base pay offered will vary depending on the market, job-related knowledge, skills and capabilities, and experience. Xaira Therapeutics an equal-opportunity employer. We believe that our strength is in our differences. Our goal to build a diverse and inclusive team began on day one, and it will never end. TO ALL RECRUITMENT AGENCIES: Xaira Therapeutics does not accept agency resumes. Please do not forward resumes to our jobs alias or employees. Xaira Therapeutics is not responsible for any fees related to unsolicited resumes.