Principal Scientist, Long-Acting Injectable Sterile Product Development
Merck
- Location
- Rahway, New Jersey, United States of America
- Employment
- Full Time
- Work model
- On-Site
- Level
- Principal
- Salary
- $173.2k – $272.6k/yr
- Posted
- Sep 4, 2026
Skills
About this role
Job Description
The Sterile Product Development group is responsible for the development of parenteral dosage forms, including long-acting injectables (LAIs), across small molecules, peptides, and biologics from preclinical development through commercialization. Our teams enable robust and scalable drug product and delivery solutions through deep scientific understanding of formulation, drug–excipient interactions, delivery system performance, and manufacturing processes, ensuring product quality, safety, efficacy, and patient-centric design. This role is a Principal Scientist–level technical leadership position with a primary focus on long-acting injectable drug products, including depot formulations, extended-release systems, and injectable sustained-delivery technologies. The successful candidate will serve as a scientific leader across multidisciplinary teams, shaping LAI formulation and development strategy across the portfolio. Primary Duties Serve as a principal-level LAI formulation scientist, providing scientific leadership for the design, development, and lifecycle management of long-acting injectable drug products, including depot, sustained-release, and controlled-delivery parenteral dosage forms Lead LAI formulation and delivery strategy development, including selection and optimization of release mechanisms (e.g., polymer-based depots, suspensions, microspheres, in situ forming systems), excipient systems, and delivery approaches to meet target product profiles Provide strategic technical leadership on cross-functional program teams, ensuring alignment of formulation, drug substance properties, delivery system performance, container/closure systems, manufacturability, and clinical use considerations throughout development Design and interpret studies to understand and control release kinetics, stability, and performance, including: Drug–excipient and drug–polymer interactions In vitro and in vivo performance relationships Physical stability, aggregation, and particle size control Syringeability, injectability, and device compatibility Support early- and late-stage development programs, including: Selection of scalable manufacturing processes for LAIs Definition of formulation and process design space Support for clinical and commercial process scale-up and validation Technology transfer to GMP manufacturing facilities Partner closely with Clinical, Non-Clinical, Quality, Regulatory, Manufacturing, and Engineering teams to: Define critical quality attributes (CQAs) and critical process parameters (CPPs) relevant to LAI performance Support clinical strategy through formulation design and risk mitigation Contribute to CMC regulatory submissions and health authority interactions Provide scientific oversight and mentoring to junior scientists, fostering capability development in LAI formulation science, experimental design, and data-driven decision making Maintain awareness of emerging LAI technologies and delivery platforms, contributing to internal capability assessments, external collaborations, and innovation initiatives aligned with portfolio and organizational strategy Minimum Education Requirements Ph.D. with 7+ years industry experience, or M.S. with 10+ years, or B.S. with 14+ years in Pharmaceutics, Pharmaceutical Sciences, Chemical Engineering, Biochemical Engineering, Chemistry, Materials Science, or a related discipline Required Experience and Skills Deep expertise in parenteral drug product development, with demonstrated experience in long-acting injectable or sustained-release formulations Strong scientific understanding of: Controlled-release mechanisms and LAI delivery systems Drug–polymer and drug–excipient interactions Formulation stability and performance characterization Experience applying Quality by Design (QbD) principles and DOE approaches to formulation and process development Experience supporting process scale-up, validation, and technology transfer for sterile injectable