Principal Scientist, Long-Acting Injectable Sterile Product Development

MSD; Rahway (NJ); On-site; USD 173,000 - 273,000; Full time

Benefits offered by this job

Annual bonus

Long-term incentive

Healthcare benefits

401(k) retirement plan

Paid holidays and vacation

Job summary

Merck & Co., Inc. in Rahway, NJ seeks a Principal Scientist to lead LAI formulation development across depot, sustained-release, and injectable delivery platforms.

You will guide cross-functional teams, design strategies for release mechanisms, and ensure robust formulation science from early development through scale-up. The role requires deep expertise in parenteral drug product development, QbD/DOE, and strong mentoring skills, with responsibility for regulatory interactions and technology

Qualifications

• Ph.D. with 7+ years industry experience or MS with 10+ years or BS with 14+ years in relevant fields.
• Deep expertise in parenteral drug product development, including LAIs and sustained-release formulations.
• Experience applying QbD and DOE to formulation/process development.
• Experience with process scale-up, validation, and technology transfer for sterile injectables.
• Knowledge of CMC regulatory expectations for parenteral/extended-release products.
• Proven ability to lead cross-functional teams and communicate complex science.

Responsibilities

• Provide scientific leadership for LAI design, development, and lifecycle management.
• Lead LAI formulation and delivery strategy development and optimization.
• Collaborate with Clinical, Regulatory, Manufacturing, and Engineering teams to align CQAs and CPPs.
• Design and interpret studies on release kinetics, stability, and performance.
• Support scale-up, process design space, and GMP manufacturing transfer.
• Mentor junior scientists and foster data-driven decision making.
• Contribute to regulatory submissions and health authority interactions.

Skills

Parenteral development

LAI formulation

QbD principles

DOE methods

Cross-functional leadership

Regulatory submissions

Mentoring

Drug–polymer interactions

Scale-up manufacturing

Sterile injectable

Education

Ph.D. with 7+ years

Job description

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 products.
• Working knowledge of CMC regulatory expectations for parenteral and extended-release products, including development-stage and commercial submissions.
• Demonstrated ability to lead cross-functional teams, influence strategy, and communicate complex scientific concepts clearly.
• Proven mentoring and scientific leadership skills at the senior/principal level.

Preferred Experience and Skills

• Experience with LAI-specific platforms, such as polymer depots, microspheres, nanosuspensions, or in situ forming systems.
• Experience with device–drug product integration, including prefilled syringes or delivery systems relevant to LAIs.
• Understanding of clinical and patient-centric considerations influencing LAI design (e.g., dosing interval, injection volume, administration route).
• Experience supporting global regulatory filings and health authority interactions.
• Track record of contributing to publications, patents, or external scientific collaborations in drug delivery or formulation science.

Required Skills

• Adaptability
• Adaptability
• Cell Culture Process Development
• Cell Line Development
• Combination Products
• Data Analysis
• Drug Delivery
• Drug Development
• Drug Formulations
• Finite Element Analysis (FEA)
• Functional Management
• Innovative Thinking
• Leadership
• Mentoring
• Pharmaceutical Process Development
• Pharmaceutical Products
• Pharmaceutical Research
• Pharmaceutical Sciences
• Pharmaceutics
• Process Development (PD)
• Process Scale Up
• Product Development
• Product Development Lifecycle
• Product Formulation
• Professional Collaboration
• Professional Networking

Employee Status and Work Details

• Regular
• Relocation: Domestic
• 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: 10/26/2026

Compensation and Benefits

• Salary range for the primary location of this role: $173,200.00 - $272,600.00
• Annual bonus and long-term incentive, if applicable
• 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

Company

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.

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.

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.

Where required by law, the compensation range for this role is provided below. The salary range for the primary location of this role is: $173,200.00 - $272,600.00 This 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.

Additional location(s) and 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 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.

Job Posting End Date: 10/26/2026 is effective until 11:59:59PM on the day BEFORE the listed 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.