We are seeking a Principal Scientist to provide technical leadership for the development of immunohistochemistry (IHC) companion diagnostics supporting oncology drug programs. This individual will serve as a subject matter expert responsible for CDx assay strategy, analytical validation, and clinical implementation from early feasibility through regulatory submission and commercialization readiness.
The Principal Scientist will lead complex CDx IHC development initiatives, ensure compliance with global regulatory and quality standards, and influence biomarker strategy through deep technical expertise. This is a hands-on scientific leadership role requiring strong collaboration with pathology, translational science, regulatory, clinical development, and external diagnostic partners to ensure successful CDx execution aligned with therapeutic timelines.
This position is full-time onsite at our Redmond, WA location.
Responsibilities CDx IHC Kit Development & Strategy- Lead development of IHC-based CDx assays and kits from early feasibility through IVD readiness.
- Define assay design, platform selection, and development strategy aligned with CDx regulatory expectations.
- Oversee antibody selection, assay optimization, and standardization across platforms (e.g., Ventana, Dako, Leica).
- Guide development of scoring algorithms, cut-offs, and interpretation frameworks with pathology leadership.
Analytical Validation & Design Control- Lead analytical validation strategy and execution for CDx IHC assays, including sensitivity, specificity, precision, accuracy, and robustness.
- Ensure validation activities meet regulatory expectations and are conducted under design control.
- Oversee preparation and approval of validation protocols, reports, and technical documentation.
- Ensure traceability, risk management, and documentation in compliance with QSR 820 and ISO 13485.
Clinical & CDx Implementation- Provide oversight for implementation of CDx IHC assays in clinical trials and central laboratories.
- Ensure assay consistency, pathologist alignment, and scoring harmonization across sites.
- Support biomarker strategy, sample plans, and clinical cut-off justification.
Regulatory & Quality- Partner with Regulatory Affairs and QA to support CDx regulatory strategy and submissions (e.g., IND/IDE, PMA/IVD).
- Ensure compliance with global regulatory requirements (FDA, NMPA, IVDR).
- Support bridging strategies from RUO/LDT to IVD CDx and contribute to regulatory interactions.
- Drive alignment with QMS, including design controls, change control, and audit readiness.
Cross-Functional Leadership- Act as subject matter expert for CDx IHC development across internal and external stakeholders.
- Lead collaborations with CROs, central labs, and IVD partners.
- Mentor team members and contribute to building CDx development capabilities.
Qualifications- PhD in Pathology, Immunology, Molecular Biology, or related life science field
- 8-12+ years of industry experience in CDx, IVD, or biomarker assay development
- Proven experience leading IHC assay development and analytical validation
- Strong knowledge of design controls and QMS (21 CFR Part 820, ISO 13485)
- Experience supporting clinical trials and CDx regulatory submissions
- Strong understanding of IHC scoring methods (TPS, CPS, H-score)
- Experience working in oncology biomarker development environments
Preferred Qualifications- Experience with approved or late-stage CDx programs
- Background in oncology biomarkers (e.g., NSCLC, GI cancers)
- Experience interacting with health authorities (FDA, NMPA, EU)
Compensation and Benefits:
The expected base salary range for this position is $130,000 - $160,000 annually. Actual compensation will be based on a variety of factors, including but not limited to a candidate's level qualifications, experience, and skills.
While most offers typically fall within the low to mid-point of the range, we may extend an offer toward the higher end for exceptional candidates whose background and expertise exceeds the requirements of the role.
SystImmune offers a comprehensive benefits package including: 100% paid employee premiums for medical/dental/vision, also STD, LTD, a 401(k) plan with a 50% company match of up to 3% and a vesting schedule of only 5 years, 15 PTO days per year, sick leave, plus 11 paid holidays and MORE.
