Senior Scientist, Pharmacokinetics

Senior Research Scientist (R3) - Biotransformation & Metabolite Identification Location: West Point, Pennsylvania (On-site) The DMPK group at our company's Research Laboratories is seeking a highly skilled and driven Senior Research Scientist (R3) with expertise in biotransformation (metabolite identification), mass spectrometry, and mechanistic enzymology. The successful candidate will leverage deep knowledge of drug metabolism and biotransformation mechanisms to design and execute experiments that identify and characterize drug metabolites, elucidate metabolic pathways, and solve complex metabolism-related challenges, supporting our drug discovery and development pipeline. You will work in a highly collaborative environment, influencing cross-functional teams through a deep understanding of how enzyme-mediated metabolic processes impact drug efficacy, safety, and developability, while driving innovation and maintaining the highest standards of scientific rigor. Primary Responsibilities Apply strong enzymology knowledge by designing and conducting targeted in vitro/in vivo studies using sub-cellular fractions, hepatocytes, recombinant enzymes and radiolabeled isotopes (3H, 14C) to elucidate biotransformation pathways and identify the enzymes responsible for metabolite formation and bioactivation. Independently design and execute experiments to profile and structurally elucidate drug metabolites, leveraging high-resolution and triple quadrupole mass spectrometers for purpose driven metabolite identification. Optimize sample preparation, chromatographic separation, and mass spectrometric techniques to improve metabolite detection and structural elucidation sensitivity and throughput. Interpret metabolite profiling data within the broader ADME/DMPK context, applying enzymology insights to correlate metabolic routes and rates with overall drug clearance, pharmacokinetics, and safety implications. Effectively document experiments and results, ensuring high-quality data capture, and clearly communicate scientific findings in electronic lab notebooks, reports, and presentations. Work closely with interdisciplinary teams to integrate metabolite identification results and mechanistic insights into broader project strategies and decision-making. Contribute to maintaining efficient lab operations, including instrument upkeep, compliance with safety and quality standards, and mentoring junior staff. Education Requirements Ph.D. in Pharmaceutical Sciences, Analytical Chemistry, Biochemistry, Pharmacology, or a related field, or a Master's degree in a relevant discipline with 4+ years of industry experience leveraging mass spectrometry for metabolite identification. (Candidates anticipating Ph.D. completion in Required Skills and Experience Clear understanding of biotransformation pathways and metabolite identification workflows (e.g., in vitro assays, metabolite isolation techniques, mass spectral analysis), with demonstrated ability to design experiments that elucidate metabolite structures and identify the enzymes involved in their formation (including bioactivation pathways). Strong written and verbal communication skills, with experience translating complex analytical data into clear, actionable conclusions and presenting findings to diverse scientific audiences. Proficiency in LC-MS operation, maintenance, and troubleshooting. Ability to work effectively on cross-functional teams and collaborate across disciplines (chemistry, biology, toxicology, etc.) to advance project goals. Excellent organizational skills, with the capability to manage multiple experiments or projects simultaneously, meet deadlines, and adapt to evolving priorities in a fast-paced environment. Preferred Skills and Experience Expertise in enzyme kinetics and factors influencing systemic metabolic rates and routes (e.g., drug-drug interactions, pharmacogenomic variations). Understanding of pharmacokinetic/pharmacodynamic (PK/PD) relationships and an appreciation of how parent drug and metabolite exposure levels impact efficacy and safety endpoints. Track record of scientific achievement through peer-reviewed publications and presentations at scientific conferences. Familiarity with regulatory guidelines on drug metabolites (e.g., ICH M3(R2) and FDA MIST guidance) and their implications for drug development. Familiarity with advanced high-resolution mass spectrometry platforms (such as time-of-flight [TOF/Q-TOF] and Orbitrap systems) and their application to metabolite identification and structural elucidation Familiarity with the preparation, handling, and analysis of radioactive samples and the use of instrumentation for radioactivity measurements. Required Skills: ADME, Biochemical Assays, Detail-Oriented, Drug Metabolism, High Resolution Mass Spectrometry (HRMS), Liquid Chromatography-Mass Spectrometry (LC-MS), Mass Spectrometry Analysis, Metabolite Identification, Pharmacokinetics, Teamwork 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. 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, background, 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 $117,000.00 - $184,200.00 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 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. Employee Status: Regular Relocation: Domestic VISA Sponsorship: No Travel Requirements: No Travel Required Flexible Work Arrangements: Not Applicable Shift: Not Indicated Valid Driving License: No Hazardous Material(s): N/A Job Posting End Date: 08/17/2026 *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. Requisition ID: R397962 #J-18808-Ljbffr Merck & Co.