Principal Assay Development Scientist (Reagent)

About Us

DELFI Diagnostics, Inc. (DELFI Diagnostics) is developing next-generation, blood-based tests that are reliable, accessible and deliver a new way to help detect cancer. Employing advanced machine-learning methods to whole-genome sequencing data, the DELFI ("DNA EvaLuation of Fragments for early Interception") platform is built to address the highest-burden health challenges. DELFI Diagnostics prioritizes solutions that have the potential to save lives on a global scale, including for historically underserved populations. DELFI Diagnostics’ platform relies on fragmentomics – the discovery that cancer cells are more chaotic than normal cells and, when they die, leave behind tell-tale patterns and characteristics of cell-free DNA (cfDNA) fragments. FirstLook Lung, for individuals eligible for lung cancer screening, is DELFI Diagnostics’ first laboratory-developed screening test and can be part of routine blood work. FirstLook Lung uses millions of data points to reliably identify individuals who may have cancer detected through low-dose CT, including early stage disease with a negative predictive value of 99.8 percent. This test has not been cleared or approved by the FDA.

In our passionate pursuit to radically improve health outcomes, we serve humanity when we:

Lead with Science, Anchor in Pragmatism: We pioneer life-changing science by ensuring quality, transparency, and rigor at all times. We explore thoughtfully, experiment smartly, and deliver impact with conviction.

Build With & For All: We embrace diverse backgrounds to innovate and achieve together. We are not just building a product - we aim to disrupt the path of cancer for all - no matter geography or socioeconomic class 

Put We over I: We are a home for high-performing people. Through teamwork, we build collective intelligence. Each of us wins when those we serve and those who serve with us--win. We show up with empathy, humility, and integrity at every step of the journey.

DELFI has 1-2 designated in-office working days each week for employees who live within within 50 miles of Palo Alto CA or Baltimore MD offices

As a Development Scientist,  you will play a critical role in developing in vitro diagnostic (IVD) reagents by establishing reagent specifications, transferring reagents to contract reagent manufacturers, and managing R&D relationships with vendors. Once reagents are established, this role will also contribute to other assay development activities for DELFI’s molecular diagnostic assays. The ideal candidate will have a strong scientific foundation in Next-Generation Sequencing (NGS) with liquid biopsies,  technical leadership, and experience working under a Design Control framework to develop and validate regulated diagnostic products.  This is a lab-based position that requires being on-site up to 5 days a week when needed.

• Lead the IVD reagent development plan execution by developing reagent specifications for finished reagents that will be used for DELFI’s molecular diagnostic assays.
• Define reagent criticality (key, ancillary, general use) for DELFI’s molecular diagnostic assays, and develop appropriate manufacturing and QC methods to conform to 21 CFR Part 820, ISO 1384, and CAP CLIA by collaborating closely with Quality and Regulatory.
• Evaluate Contract Reagent Manufacturers to transfer the reagents manufacturing. Be the primary point of contact and accountable for the completion of process development and the generation of pilot builds for R&D needs by developing various scopes of work (SOWs) and helping implement supplier agreements.
• Establish R&D relationships with different vendors and participate in Quality audits.
• Plan reagent stability to set preliminary expiry specifications required for Verification and Validation activities.
• Perform rigorous design of experiment, data analysis, and act as subject matter expert by collaborating with assay biostatisticians, bioinformaticians, engineers, and scientists. Participate in laboratory on-site work when required.
• Maintain reagent development plan, develop reagent FMEA, and contribute to other design documents such as protocols and reports under Design Control to meet product development and project milestones.

• Successful execution of the reagent development plan and transfer of reagent manufacturing to a contract reagent manufacturer.
• Be able to understand regulatory requirements, perform risk assessments, and participate in the elaboration of plans and data-driven decisions to prioritize IVD development.

• Required
• PhD with 7+ years or Master’s with 10+ years industry assay/reagent development with experience in Molecular Biology, Biochemistry, Chemistry, or a similar discipline.
• 3+ years of developing IVD diagnostic tests with NGS cfDNA/multi-omic assay technologies from plasma (e.g., DNA fragments, RNA, small variants, methylation, or immunoassays).
• 2+ years of experience developing reagent specifications (format, fill volume tolerance, closure, label, shelf, and in-use stability), reagent integrations with automated platforms, and transferring reagent manufacturing from R&D to an internal department or an external contract reagent manufacturer.
• Hands-on with reagent development and assay optimization for IVD or LDT product development experience, working in a regulated laboratory environment (GLP).
• Experience in writing protocols, designing experiments, analyzing, and documenting results in reports.
• Clear communication skills, ability to work with team members in the same and adjacent disciplines, and experience mentoring and training junior scientists and other cross-functional stakeholders to foster a collaborative, knowledge-sharing and data-driven culture.
• Ability to work on-site at our Palo Alto laboratory five days a week when required to be hands-on in the laboratory, with periodic travel to the reagent manufacturer sites for audit purposes.
• Preferred
• Experience with IVD reagent kitting and reagent interchangeability
• Experience in developing reagent QC methods and Process Validation for reagent manufacturing.
• Experience in managing R&D relationships and auditing reagent suppliers.

We are an equal opportunity employer and value diversity at our company. We do not discriminate on the basis of race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status.

This position is not eligible for agency partnership. Resumes and outreach from staffing representatives will be declined.