Protein Engineering — Senior Principal Scientist / Associate Director / Director

While professional experience and qualifications are key for this role, make sure to check you have the preferable soft skills before applying if required.

Location: Seattle, WA (onsite) Company: Breakwater Therapeutics (stealth mode)

About the Company We’re an early-stage venture-backed biotech operating in stealth mode, and we are focused on mAb-based therapeutics. We’re building a nimble team that thrives in ambiguity, moves quickly from idea to experiment, and collaborates closely across science and operations to inform decision-making.

The Opportunity This is a foundational, first-in-lab hire. You’ll help stand up our internal lab—procure and commission equipment, establish day-to-day workflows, and set the bar for scientific rigor, safety, and documentation—while running critical protein production, characterization, and developability workstreams that de-risk and accelerate our programs.

What You’ll Do

Build and run the lab Stand up the lab (BSL-2 environment), including instrument selection/commissioning, qualification, preventive maintenance, inventory, ELN/LIMS, and safety/compliance workflows. Own day-to-day operations (ordering/receiving, vendor coordination, facilities interface, waste streams, calibrations).

Protein production & purification Execute small-scale antibody production for assay supply (e.g., transient CHO-K1), including cloning handoff, transfection, expression, and harvest. Produce recombinant antigens to support binding assays (e.g., ELISA/BLI). Purify proteins using standard workflows (Affinity → polishing via IEX/SEC); perform routine analytics (UV/Vis, SDS-PAGE, CE-SDS, HPLC-SEC).

Binding & comparability Design and run ELISAs and BLI-based binding assays; perform FcRn binding across relevant pH conditions for comparability/PK-enabling readouts.

Developability triage Execute rapid biophysical screens (e.g., nanoDSF/DSF-light, DLS, micro/small-scale viscosity, analytical SEC) to flag liabilities early and prioritize leads.

Formulation scouting Screen buffers/excipients and assess impacts on aggregation, stability, and viscosity; contribute to formulation strategy for high-concentration readiness.

Collaboration & communication Operate and troubleshoot independently with strategic oversight from the CSO; summarize and present data clearly for senior leadership decision-making. Coordinate with external partners/CROs to complement internal capabilities and shorten cycle times. Author technical reports and contribute to regulatory submissions

Mentorship As the team grows, provide day-to-day guidance to 1–2 Research Associates (prioritization, data review, SOP/safety adherence) while remaining a hands-on contributor. Train and onboard RAs on core workflows (transient CHO expression, purification, ELISA/BLI) to ensure consistency and quality.

What You’ll Bring

Minimum qualifications Ph.D. (or equivalent doctorate: PhD/DPhil/ScD) in protein sciences, biochemistry, bioengineering, or related field; 5+ years of relevant industry experience preferred. Hands-on expertise with mammalian transient CHO-K1 expression for antibodies and recombinant protein production. Solid purification skills (Protein A/affinity, IEX, SEC) and routine analytics (SDS-PAGE, HPLC-SEC). Practical experience with ELISA and BLI (Octet or similar) assay design, execution, and data analysis. Experience running developability/biophysical methods (e.g., DSF/DSC-light, DLS, small-scale viscosity, analytical SEC). Familiarity with formulation buffer/excipient screening and stability assessments. Proven ability to operate and troubleshoot independently in a fast-moving lab; strong documentation discipline (ELN/SOPs) and data visualization skills for cross-functional audiences.

Preferred qualifications Experience setting up a new lab or significantly expanding lab capabilities (procurement, instrument commissioning, safety programs). Direct experience in mAb protein engineering, such as affinity maturation (display libraries or computational-guided), humanization and deimmunization (B/T-cell epitope risk mitigation), Fc/Fab engineering (including FcRn and effector tuning), and stability/solubility/developability engineering Formulation DOE for buffer/excipient optimization and high-concentration suitability FcRn binding assay execution/interpretation Comfort with high-throughput plate-based workflows and basic automation. Working knowledge of statistics for assay development/acceptance criteria. Prior collaboration with CROs/CDMOs; ability to draft/track study plans and QC data packages. Knowledge of GMP requirements and ICH guidelines

Traits for success Highly motivated self-starter with high activation energy, scientific curiosity, and a roll-up-your-sleeves mindset. Flexible, detail-oriented, and quality-driven; eager to learn new methods and optimize workflows. Clear, concise communicator who can distill complex data for senior leadership and cross-functional partners.

Tools & Environment (representative) Mammalian culture (shakers/incubators/CO₂), FPLC/ÄKTA or equivalent, plate readers, BLI (Octet or similar), HPLC-SEC, DLS, nanoDSF/DSF, viscometry, basic chem/biochem lab equipment; ELN and inventory systems.

Title & Level

Level open: we anticipate hiring between Senior Principal Scientist and Director ; exceptional Scientist/Senior Scientist candidates will also be considered.

Why Join Us Play a foundational role in a venture-backed startup, shaping both the science and the lab culture. Work closely with seasoned company builders and scientific leadership across the Frazier Life Sciences network.

Equal Opportunity Employer. We are an equal opportunity employer and celebrate diversity. We’re committed to building an inclusive environment for all employees.

How to Apply: Please send your CV and a brief note highlighting relevant hands-on experience with CHO-based expression, binding assays (ELISA/BLI), and developability screening.