Scientist/Senior Scientist, Companion Diagnostics (CDx) – IHC Development
About The Position
SystImmune is a leading and well-funded clinical-stage biopharmaceutical company located in Redmond, WA and Princeton, NJ. It specializes in developing innovative cancer treatments using its established drug development platforms, focusing on bi-specific, multi-specific antibodies, and antibody-drug conjugates (ADCs). SystImmune has multiple assets in various stages of clinical trials for solid tumor and hematologic indications. Alongside ongoing clinical trials. SystImmune has a robust preclinical pipeline of potential cancer therapeutics in the discover and IND-enabling stages, representing cutting-edge biologics development. We offer an opportunity for you to learn and grow while making significant contributions to the company's success. We are seeking a Scientist or Senior Scientist to lead and support immunohistochemistry (IHC) assay development for companion diagnostic (CDx) kits supporting oncology drug development. This role is responsible for end-to-end IHC assay development, including antibody selection, assay optimization, analytical validation, and clinical trial implementation, with a clear development path from RUO/LDT to IVD CDx commercialization. The ideal candidate has strong expertise in pathology, IHC assay development, and CDx regulatory expectations, and can work effectively across R&D, clinical, regulatory, QA, and external CROs and central laboratories.
Requirements
- PhD in Pathology, Molecular Biology, Immunology, Oncology, or a related field
- MS or BS with significant CDx or IVD industry experience may be considered
- 3–5+ years of hands-on experience in IHC assay development, preferably in a CDx or IVD setting
- Direct experience supporting oncology biomarkers and clinical trials
- Experience across the CDx development lifecycle (RUO/LDT through IVD readiness)
- Strong understanding of IHC scoring methodologies (e.g., TPS, H-score, CPS)
- Familiarity with analytical validation and regulatory expectations for CDx
- Demonstrated ability to work effectively in cross-functional teams
- Strong scientific rigor with excellent documentation and data interpretation skills
- Ability to operate in a fast-paced, matrix environment
- Clear and effective communication with both technical and non-technical stakeholders
- Experience working with global teams is a plus
Nice To Haves
- Prior experience with late-stage or FDA-approved CDx programs
- Experience developing and justifying biomarker cut-off strategies
- Familiarity with NSCLC, GI cancers, or other solid tumors
- Experience interacting with health authorities or supporting regulatory meetings
Responsibilities
- Lead development of IHC-based CDx assays, from biomarker discovery through assay optimization and validation.
- Select and evaluate primary antibodies, detection systems, and staining platforms (e.g., Ventana, Dako, Leica).
- Optimize assay parameters, including epitope retrieval, antibody dilution, detection chemistry, and staining conditions.
- Establish scoring algorithms, cut-off strategies, and interpretation guidelines in collaboration with pathologists.
- Support biomarker strategies for patient selection and stratification in clinical trials.
- Design and oversee analytical performance studies, including: Sensitivity and specificity Precision and reproducibility (intra-run, inter-run, inter-site) Accuracy and robustness Linearity and limit of detection, where applicable
- Prepare, review, and approve validation protocols, reports, and SOPs in alignment with CDx expectations.
- Support implementation of IHC assays in clinical trials, including: Central laboratory qualification and oversight Pathologist training and alignment Slide logistics, staining consistency, and scoring harmonization
- Collaborate with clinical teams on sample strategy, feasibility studies, and biomarker cut-off justification.
- Work closely with Regulatory Affairs and Quality Assurance to ensure compliance with: FDA CDx guidance (US) NMPA/CDE requirements (China), where applicable IVDR (EU), as relevant
- Support preparation of regulatory documentation, including: IDE/IND biomarker sections CDx bridging strategies (RUO/LDT → IVD) Analytical and clinical performance summaries
- Ensure assay development aligns with QMS requirements, design controls, and document traceability.
- Serve as a technical subject-matter expert, interacting with: CROs, central laboratories, and IVD partners Antibody vendors and staining platform providers
- Provide scientific input to project teams, governance meetings, and external collaborations.
- Mentor junior scientists and contribute to team capability building, as appropriate.
Benefits
- 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.
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What This Job Offers
Job Type
Full-time
Career Level
Mid Level
Education Level
Ph.D. or professional degree
Number of Employees
11-50 employees
