Associate Principal Scientist, Biopharmaceutics

Job DescriptionWe are seeking an experienced Associate Principal Scientist to join our team and lead biopharmaceutics strategy for subcutaneously (SC) administered biologics across the pipeline—from early formulation screening through late-stage commercialization and lifecycle management. Working in close collaboration with formulation, analytical, device engineering, pharmacokinetics, and clinical pharmacology teams, you will apply fundamental mechanistic principles, quantitative translational modeling, and experimental frameworks to evaluate SC absorption, formulation and device compatibility, product bridging, and immunogenicity risk. The ideal candidate will combine deep scientific rigor with strong matrix leadership to de-risk clinical delivery and influence program decision-making at key governance milestones.Key Responsibilities:Lead SC Biopharmaceutics Strategy: Define integrated experimental and modeling strategies to guide formulation, dose volume, injection site, and device decisions across development.Drive Translation and Product Bridging: Apply mechanistic and quantitative approaches to translate preclinical findings, assess exposure variability, and support formulation, device, process, scale, and site changes.Assess Immunogenicity and Bio performance Risk: Evaluate how product quality attributes, formulation, particles, aggregates, and delivery conditions may affect local tolerability, pharmacokinetics, and immunogenicity.Influence Governance and Regulatory Strategy: Communicate risks and recommendations at program and governance forums and author or review relevant regulatory submissions and health authority briefing materials.Advance Scientific Capabilities: Develop predictive tools and experimental approaches, mentor scientists, and contribute to external scientific engagement.Qualifications:Education Minimum Requirements:Ph.D. in Pharmaceutical Sciences, Biochemistry, Chemical or Biomedical Engineering, or related scientific disciplinewith 3+ years of relevant experience; ORMaster’s degree in a relevant discipline with 8+ years of relevant industry experience.Required Experience and Skills:Demonstrated expertise in biologics drug product development with a strong focus on the mechanistic principles governing subcutaneous absorption, interstitial transport, and translational pharmacokinetics.Proven track record as a biopharmaceutics, formulation, or translational PK lead within cross-functional matrix development teams.Hands-on experience developing and executing biopharmaceutics risk assessments for product comparability, device transitions (e.g., vial to PFS/autoinjector), and formulation bridging.Working understanding of the interplay between biologic quality attributes (e.g., aggregation, opalescence, viscosity, particle formation), delivery devices, and clinical immunogenicity / ADA impact.Strong critical thinking and problem solving, with the ability to translate complex or incomplete data into clear development decisions.Outstanding oral, written, and presentation skills, with the ability to communicate technical complexity clearly to senior leadership and cross-functional teams.Preferred Experience and Skills:Hands-on proficiency with mechanistic modeling and simulation platforms (e.g., GastroPlus, Simcyp, Phoenix WinNonlin, PK-Sim, MATLAB, or Python/R).Experience with high-concentration and/or large-volume SC biologic delivery, including co-formulation approaches or permeation-enhancing technologies.Direct experience authoring biopharmaceutics and comparability sections for regulatory filings (IND/BLA) or supporting agency briefing books.Prior experience evaluating device-biologic interactions and human factors considerations for pre-filled syringes, autoinjectors, or wearable delivery systems.Record of sustained scientific contributions, including peer-reviewed publications, invited presentations, or active participation in cross-industry consortia.Required Skills:Biologics Drug Product, Biopharmaceutics, Bridging Strategies, Comparability, Drug Delivery, Formulation Characterization, Immunogenicity Risk Assessment, In Vitro-In Vivo Translation, Matrix Leadership, Pharmacokinetics (PK), Pre-Filled Syringes & Autoinjectors, Regulatory Submissions, Subcutaneous Absorption, Translational Modeling.Required Skills: Biopharmaceuticals, Cell Line Development, Clinical Pharmacology, Downstream Process Development, Drug Delivery Technology, Drug Development, Expression Vectors, Immunogenicity, Molecular Biology, Pharmaceutical Formulations, Pharmaceutical Process Development, Pharmaceutical Sciences, Pharmacokinetics, Physical Characterization, Stable Cell LinesPreferred Skills: Current Employees apply HERECurrent Contingent Workers apply HEREUS 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 RightsEEOC 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 ActsThe primary location for this posting is:USA - New Jersey - RahwayWhere required by law, the compensation range for this role is provided below.The salary range for the primary location of this role is:$142,400.00 - $224,100.00This range reflects the Company's reasonable expectation of the base salary applicable to this role at the time of 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 .Additional location(s): Please note the salary range above applies to the Primary Location of the position. Where a role has other listed locations, different compensation guidelines may apply. You may find the salary ranges for additional locations below. If the salary range is not listed for the location you are applying to, our Talent Acquisition team will provide further information to you relevant to your location.Additional location(s) Compensation Information:San Francisco Residents Only: We will consider qualified applicants with arrest and conviction records for employment in compliance with the San Francisco Fair Chance OrdinanceLos 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 OrdinanceSearch 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: RegularRelocation:DomesticVISA Sponsorship:NoTravel Requirements:10%Flexible Work Arrangements:Not ApplicableShift:Not IndicatedValid Driving License:NoHazardous Material(s):n/sJob Posting End Date:11/20/2026*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. SummaryLocation: USA - New Jersey - RahwayType: Full time