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Salary
$72k – $196k per year (Estimated)
Location
Remote (United Kingdom)
Seniority
Principal
Employment
Full-Time
Overview
Company
Impact
Profile match
Merck & Co. is an American pharmaceutical company founded in 1891 as the United States arm of the German firm Merck and made independent after the First World War, trading as MSD outside the United States and Canada. Its portfolio is dominated by the immuno-oncology drug Keytruda, alongside vaccines such as Gardasil and Vaxneuvance, hospital acute care products, and a large animal health business covering livestock and companion animals. The company is headquartered in Rahway, New Jersey, listed on the New York Stock Exchange, and spends a very large share of revenue on research into oncology, infectious disease and cardiometabolic therapies.

Job Description

The Associate Principal Scientist reports into the External Capabilities group within Small Molecule Process Research & Development.

The successful candidate will be responsible for providing scientific leadership and oversight for teams of scientists at our external partners. The role provides regular scientific direction and timely problem-solving in the areas of synthetic route design, route scouting, process optimization and development, and active pharmaceutical ingredient, API, delivery in support of the Company’s small-molecule pipeline.

The incumbent collaborates effectively with Process Chemistry, Discovery Process Chemistry, Enabling Technologies, Chemical Engineering Research & Development, Analytical Research & Development, Quality, and other partner groups to develop innovative and practical solutions to synthetic chemistry and process-development challenges. The individual will work across internal and external teams to help ensure successful API deliveries under demanding project timelines.

The position requires strong subject-matter expertise in synthetic organic chemistry and broad knowledge of pharmaceutical development. The incumbent is expected to apply sound scientific judgment, identify and manage technical risks, and influence project teams through data-driven recommendations and effective problem-solving.

As a scientific contributor and project leader within Small Molecule Process Research & Development, the incumbent is expected to build a broad internal network, contribute technically and strategically across a portfolio of programs, and support the scientific development of colleagues within the organization. The individual may mentor less-experienced scientists and contribute to functional or cross-functional scientific initiatives.

The Associate Principal Scientist builds and maintains strong working relationships with scientists and management at strategic external partners. The incumbent promotes a culture of scientific excellence, trust, collaboration, quality, safety, and compliance across Company and partner teams.

Strong communication, negotiation, influencing, and relationship-management skills are essential for establishing effective partnerships across diverse geographies and cultures. The successful candidate must be able to communicate technical expectations clearly, constructively challenge scientific proposals, align stakeholders, and drive external teams toward high-quality and timely outcomes.

Primary Responsibilities

  • Provide scientific leadership and day-to-day technical oversight for process chemistry activities conducted at external partners.

  • Guide synthetic route design, route scouting, process optimization, reaction understanding, impurity-control strategy, process robustness, and preparation of intermediates and APIs.

  • Serve as a key scientific interface between external partners and internal project teams, ensuring that technical priorities, deliverables, risks, and timelines are clearly understood.

  • Critically evaluate experimental plans, data packages, development reports, and technical proposals from external partners.

  • Identify emerging scientific, operational, quality, and delivery risks, and work with internal and external stakeholders to establish practical mitigation plans.

  • Apply innovative and rigorous problem-solving approaches to complex synthetic chemistry and process-development challenges.

  • Collaborate with Process Chemistry, Discovery Process Chemistry, Enabling Technologies, Chemical Engineering Research & Development, Analytical Research & Development, Quality, and other partner functions to advance programs and support successful API delivery.

  • Contribute to technical and strategic decisions for assigned projects or a portfolio of programs through clear, data-based recommendations.

  • Establish productive relationships with scientists and management at external partner organizations and promote transparent communication and timely issue escalation.

  • Support effective knowledge transfer between external partners and internal project teams.

  • Promote high standards of scientific rigor, documentation, quality, data integrity, safety, and compliance across external activities.

  • Contribute to the development and implementation of external capability strategies, working practices, scientific standards, and continuous-improvement initiatives.

  • Mentor and support the scientific development of colleagues and external-partner scientists, as appropriate.

  • Communicate project progress, technical risks, key decisions, and recommended actions clearly to scientific and cross-functional stakeholders.

Qualifications

Education Requirement

  • Ph.D. in synthetic organic chemistry or a closely related field.

Required Experience and Skills

  • Relevant pharmaceutical or biotechnology industry experience in synthetic chemistry, process chemistry, or closely related drug-development activities.

  • Demonstrated ability to independently lead complex scientific activities and effectively guide multidisciplinary or external project teams.

  • Strong knowledge of synthetic organic chemistry, route design, process development, reaction optimization, impurity control, and scale-up considerations.

  • Demonstrated record of delivering high-quality scientific results through innovation, sound judgment, and proactive problem-solving.

  • Ability to critically analyze complex experimental data, identify technical risks, and recommend practical development strategies.

  • Experience collaborating across scientific and operational functions to achieve project objectives and delivery commitments.

  • Strong interpersonal, written, and verbal communication skills.

  • Effective negotiation, influencing, collaboration, and relationship-management skills.

  • Ability to work effectively across organizational boundaries, cultures, geographies, and time zones.

  • Demonstrated commitment to scientific excellence, data integrity, quality, safety, compliance, and ethical decision-making.

  • Evidence of scientific contribution through publications, presentations, patents, internal technical reports, process-development accomplishments, or other relevant forms of scientific impact.

  • Ability and willingness to travel approximately 25% of the time, based on business needs.

Preferred Experience

  • Experience providing scientific oversight for work performed at contract development and manufacturing organizations or other external research and development partners.

  • Experience with synthetic route development and process scale-up from laboratory studies through multikilogram or manufacturing-scale execution.

  • Experience supporting API deliveries across one or more stages of pharmaceutical development.

  • Familiarity with technology transfer, external manufacturing, analytical control strategies, process safety, quality systems, and regulatory expectations relevant to pharmaceutical development.

  • Experience working on multiple projects or programs with competing technical priorities and timelines.

  • Experience mentoring scientists or providing technical guidance to project teams.

  • Demonstrated ability to establish effective working relationships with external scientists, project leaders, and partner-site management.

We are proud to be a company that embraces the value of bringing diverse, talented, and committed people together. The fastest way to breakthrough innovation is when diverse ideas come together in an inclusive environment. We encourage our colleagues to respectfully challenge one another’s thinking and approach problems collectively. We are an equal opportunity employer, committed to fostering an inclusive and diverse workplace.

Required Skills:

Analytical Chemistry, Chemical Synthesis, Chemistry, Clinical Judgment, Contract Research Organizations (CROs), Cross-Cultural Awareness, Data Analysis, Next Generation Science Standards, Organic Chemistry, Research Development, Researching, Scientific Analysis, Scientific Presentations, Scientific Research, Scientific Reviews, Small Molecules, Synthetic Chemistry

Preferred Skills:

Current Employees apply HERE

Current Contingent Workers apply HERE

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:

VISA Sponsorship:

Travel Requirements:

Flexible Work Arrangements:

Remote

Shift:

Valid Driving License:

Hazardous Material(s):

Job Posting End Date:

09/24/2026

*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.

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