Principal Scientist, Toxicologist/Study Director

Job Description Principal Scientist, Toxicologist/Study Director Job Description: The Nonclinical Drug Safety department is seeking a motivated and talented toxicologist with immunology and/or biologics experience to conduct and/or monitor toxicity studies (GLP and non-GLP) as a Study Director or Study Monitor and serve as a departmental representative on drug development teams. Toxicologists at our Company are integral members and leaders of collaborative cross functional scientific teams, addressing challenges from early discovery to late development. Our toxicologists provide scientific leadership in the design and overall conduct of in vivo studies and integrate the findings from all contributing scientists into reports that characterize the safety profile of drug candidates. Key Responsibilities Serve as the single point of control (Study Director) on assigned acute through chronic general toxicology studies across all modalities. Interact with technical, veterinary, and scientific staff to ensure that the study is in compliance with the protocol, amendments, Standard Operating Procedures, regulations, safety guidelines, and company policies and procedures. Critically analyze and interpret data. Integrate data from other areas (e.g., clinical pathology, pathology, toxicokinetics) in written reports used for regulatory submissions, and communicate results within established timelines. Ensure regulatory rigor, proactive risk identification, and timely study execution. Participate on cross-functional group teams to investigate mechanisms of toxicity, utilizing additional tools and applications that are available on site. Serve as a departmental representative on a product development team, overseeing the strategy and design of nonclinical safety studies and generation of regulatory strategies and communications with global regulatory agencies to support the development of drug candidates. Demonstrate enterprise mindset and strategic thinking, proactively identifying opportunities, anticipating challenges, and contributing to solutions aligned with broader organizational priorities. Build strong collaborative relationships and influences without authority, contributing to an inclusive team environment and actively learning to coach, develop, and elevate others. Deliver high-quality results with accountability and agility, translating objectives into action while continuously improving, embracing change, and showing potential to lead larger initiatives over time. Education PhD and/or DVM with graduate and/or post-graduate work training in toxicology, pharmacology, or related scientific discipline Requirements Minimum of 8 (eight) years of relevant experience as a Toxicologist or Study Director in pharma, biotech, or at a CRO Demonstrated understanding of and experience with Good Laboratory Practices (US FDA 21 CFR Part 58) Strong interest in collaborating with diverse cross-functional teams and communicating openly and often with colleagues Strong listening, collaboration, and leadership skills Ability to communicate clearly using verbal and written formats, including presentations and meetings Expertise in immunology and/or biologics, especially regulatory requirements and testing Preferred Knowledgeable about drug developmentstrategies for biotherapeutics and large molecules Familiarity with outsourced study monitoring Experience serving as toxicology expert on a drug discovery and development team Representation of nonclinical safety in regulatory agency interactions Required Skills: Clinical Immunology, Clinical Pathology, Cross-Functional Teamwork, Detail-Oriented, Environmental Toxicology, Experimentation, GLP Regulations, Good Laboratory Practices (GLPs), Identifying Risks, Immunoassays, Immunology, Immunotherapy, Mentoring Staff, Preclinical Toxicology (Inactive), Professional Integrity, Professional Networking, Regulatory Requirements, Report Preparation, Study Directing, Study Monitoring, Technical Advising, Toxicity Studies, Toxicology, Toxicology Research Preferred Skills: Current Employees apply HERE Current Contingent Workers apply HERE US and Puerto Rico Residents Only: Our company is committed to inclusion, ensuring that candidates can engage in a hiring process that exhibits their true capabilities. Please click here if you need an accommodation during the application or hiring process. As an Equal Employment Opportunity Employer, we provide equal opportunities to all employees and applicants for employment and prohibit discrimination on the basis of race, color, age, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, disability status, or other applicable legally protected characteristics. As a federal contractor, we comply with all affirmative action requirements for protected veterans and individuals with disabilities. For more information about personal rights under the U.S. Equal Opportunity Employment laws, visit: EEOC Know Your Rights EEOC GINA Supplement We are proud to be a company that embraces the value of bringing together, talented, and committed people with diverse experiences, perspectives, skills and backgrounds. The fastest way to breakthrough innovation is when people with diverse ideas, broad experiences, backgrounds, and skills come together in an inclusive environment. We encourage our colleagues to respectfully challenge one another’s thinking and approach problems collectively. Learn more about your rights, including under California, Colorado and other US State Acts The salary range for this role is $173,200.00 - $272,600.00 This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An employee’s position within the salary range will be based on several factors including, but not limited to relevant education, qualifications, certifications, experience, skills, geographic location, government requirements, and business or organizational needs. The successful candidate will be eligible for annual bonus and long-term incentive, if applicable. We offer a comprehensive package of benefits. Available benefits include medical, dental, vision healthcare and other insurance benefits (for employee and family), retirement benefits, including 401(k), paid holidays, vacation, and compassionate and sick days. More information about benefits is available at You can apply for this role through (or via the Workday Jobs Hub if you are a current employee). The application deadline for this position is stated on this posting. San Francisco Residents Only: We will consider qualified applicants with arrest and conviction records for employment in compliance with the San Francisco Fair Chance Ordinance Los Angeles Residents Only: We will consider for employment all qualified applicants, including those with criminal histories, in a manner consistent with the requirements of applicable state and local laws, including the City of Los Angeles’ Fair Chance Initiative for Hiring Ordinance Search Firm Representatives Please Read Carefully Merck & Co., Inc., Rahway, NJ, USA, also known as Merck Sharp & Dohme LLC, Rahway, NJ, USA, does not accept unsolicited assistance from search firms for employment opportunities. All CVs / resumes submitted by search firms to any employee at our company without a valid written search agreement in place for this position will be deemed the sole property of our company. No fee will be paid in the event a candidate is hired by our company as a result of an agency referral where no pre-existing agreement is in place. Where agency agreements are in place, introductions are position specific. Please, no phone calls or emails. Employee Status: Regular Relocation: Domestic/International VISA Sponsorship: Yes Travel Requirements: 10% Flexible Work Arrangements: Not Applicable Shift: Not Indicated Valid Driving License: No Hazardous Material(s): N/A Job Posting End Date: 07/23/2026 *A job posting is effective until 11:59:59PM on the day BEFORE the listed job posting end date. Please ensure you apply to a job posting no later than the day BEFORE the job posting end date. Our company is a global health care leader with a diversified portfolio of prescription medicines, vaccines and animal health products. The difference between potential and achievement lies in the spark that fuels innovation and inventiveness; this is the space where we have codified our legacy for over a century. Our success is backed by ethical integrity, forward momentum, and an inspiring mission to achieve new milestones in global healthcare.