Scientist/Senior Scientist, Companion Diagnostics (CDx) – IHC Development

<div><div style="width:6.6493in;"><div style="width:6.6493in;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;">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.<br>&#160;<br><span style="line-height:115%;">We are seeking a <strong>Scientist or Senior Scientist </strong>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.</span><br><br><span style="line-height:115%;">The ideal candidate has strong expertise in pathology, IHC assay development, and CDx regulatory expectations, and can work effectively across R&amp;D, clinical, regulatory, QA, and external CROs and central laboratories.</span><br><br><b><span style="line-height:115%;">Key Responsibilities</span></b><br><br><span style="line-height:115%;"><b>IHC Assay &amp; CDx Development</b></span></span></span><ul style="margin-bottom:11px;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Lead development of IHC-based CDx assays, from biomarker discovery through assay optimization and validation.</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Select and evaluate primary antibodies, detection systems, and staining platforms (e.g., Ventana, Dako, Leica).</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Optimize assay parameters, including epitope retrieval, antibody dilution, detection chemistry, and staining conditions.</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Establish scoring algorithms, cut-off strategies, and interpretation guidelines in collaboration with pathologists.</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Support biomarker strategies for patient selection and stratification in clinical trials.</span></span></span></li></ul><br><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;"><b>Analytical Validation &amp; Performance</b></span></span></span><ul style="margin-bottom:11px;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Design and oversee analytical performance studies, including:</span></span></span><ul style="list-style-type:circle;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Sensitivity and specificity</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Precision and reproducibility (intra-run, inter-run, inter-site)</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Accuracy and robustness</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Linearity and limit of detection, where applicable</span></span></span></li></ul></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Prepare, review, and approve validation protocols, reports, and SOPs in alignment with CDx expectations.</span></span></span></li></ul><br><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;"><b>Clinical Trial &amp; Central Lab Support</b></span></span></span><ul style="margin-bottom:11px;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Support implementation of IHC assays in clinical trials, including:</span></span></span><ul style="list-style-type:circle;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Central laboratory qualification and oversight</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Pathologist training and alignment</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Slide logistics, staining consistency, and scoring harmonization</span></span></span></li></ul></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Collaborate with clinical teams on sample strategy, feasibility studies, and biomarker cut-off justification.</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;"><b>Regulatory &amp; Quality Collaboration</b></span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Work closely with Regulatory Affairs and Quality Assurance to ensure compliance with:</span></span></span><ul style="list-style-type:circle;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">FDA CDx guidance (US)</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">NMPA/CDE requirements (China), where applicable</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">IVDR (EU), as relevant</span></span></span></li></ul></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Support preparation of regulatory documentation, including:</span></span></span><ul style="list-style-type:circle;"><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">IDE/IND biomarker sections</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">CDx bridging strategies (RUO/LDT &#8594; IVD)</span></span></span></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Analytical and clinical performance summaries</span></span></span></li></ul></li><li style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;">Ensure assay development aligns with QMS requirements, design controls, and document traceability.</span></span></span></li></ul><div style="margin-bottom:11px;"><span style="font-size:14px;"><span style="font-family:Arial, Helvetica, sans-serif;"><span style="line-height:115%;"><b>Cross-Functional &amp; External Collaboration</b></span></span></span>