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 will bring strong expertise in pathology, IHC assay development, and CDx regulatory expectations, and will be able to collaborate effectively across R&D, clinical, regulatory, quality assurance, and external CROs and central laboratories.
Key Responsibilities IHC Assay & CDx Development
- 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.
- 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 to 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, 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.
- PhD in Pathology, Molecular Biology, Immunology, Oncology, or a related field
- MS or BS with significant CDx or IVD industry experience may also 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, from RUO/LDT through IVD readiness
- Strong understanding of IHC scoring methodologies such as TPS, H-score, and 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, matrixed environment
- Clear and effective communication with both technical and non-technical stakeholders
- Experience working with global teams is a plus
- 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
Estimated Min Rate: $98000.00
Estimated Max Rate: $140000.00
What’s In It for You?
We welcome you to be a part of the largest and legendary global staffing companies to meet your career aspirations. Yoh’s network of client companies has been employing professionals like you for over 65 years in the U.S., UK and Canada. Join Yoh’s extensive talent community that will provide you with access to Yoh’s vast network of opportunities and gain access to this exclusive opportunity available to you. Benefit eligibility is in accordance with applicable laws and client requirements. Benefits include:
- Medical, Prescription, Dental & Vision Benefits (for employees working 20+ hours per week)
- Health Savings Account (HSA) (for employees working 20+ hours per week)
- Life & Disability Insurance (for employees working 20+ hours per week)
- MetLife Voluntary Benefits
- Employee Assistance Program (EAP)
- 401K Retirement Savings Plan
- Direct Deposit & weekly epayroll
- Referral Bonus Programs
- Certification and training opportunities
Note: Any pay ranges displayed are estimations. Actual pay is determined by an applicant's experience, technical expertise, and other qualifications as listed in the job description. All qualified applicants are welcome to apply.
Yoh, a Day & Zimmermann company, is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.
Visit https://www.yoh.com/applicants-with-disabilities to contact us if you are an individual with a disability and require accommodation in the application process.
For California applicants, qualified applicants with arrest or conviction records will be considered for employment in accordance with the Los Angeles County Fair Chance Ordinance for Employers and the California Fair Chance Act. All of the material job duties described in this posting are job duties for which a criminal history may have a direct, adverse, and negative relationship potentially resulting in the withdrawal of a conditional offer of employment.
It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.
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