
R&D
Where your curiosity drives the
miracles of
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Senior Scientist, Process Chemistry
At a glance
Bring your curiosity to a team where deep immunoscience meets cutting-edge innovation. Across oncology, rare diseases, neurology, and vaccines, you’ll work at the intersection of lab science and AI-powered discovery — all while collaborating across boundaries to turn breakthrough ideas into real-world impact. Whether you want to deepen your scientific expertise or grow as a leader, you’ll find the opportunity here.
Job Title: Senior Scientist, Process Chemistry
Location: Cambridge, MA
About the Job
We are an innovative global healthcare company with one purpose: to chase the miracles of science to improve people’s lives. We’re also a company where you can flourish and grow your career, with countless opportunities to explore, make connections with people, and stretch the limits of what you thought was possible. Ready to get started?
The Commercial Process Development team, part of the CMC Synthetics Platform within the Sanofi R&D organization, is responsible for mid-to-late-stage process development for drug substances undergoing clinical development and for the chemical process to deliver the drug substance quality target profile. The Chemical Process Development team owns the eco-design strategy for the drug substance and, in collaboration with Analytical Sciences, Process Engineering and Clinical Manufacturing/External Technologies, defines the control strategy for the DS synthetic process. We strongly believe that innovation in synthetic concepts and technologies, leveraging modeling, AI/ML and integration of biocatalysis are key drivers to transform drug substance process development to deliver drug substances in the most efficient, robust, economical, environmentally benign, and intrinsically safe way.
We are looking for a highly motivated and collaborative individual with expertise in synthetic organic chemistry, late-stage clinical development experience to join our Process Chemistry team at the Principal Scientist level. Under the direction of Process Chemistry R&D leadership, the primary responsibility of this role is to perform and oversee multi-step route evaluation and route development activities, with the aim of establishing commercial drug substance manufacturing processes through management and execution of internal and outsourced laboratory activities. This role may oversee the activities of one or more collaborators and be responsible for their professional development.
We are an innovative global healthcare company with one purpose: to chase the miracles of science to improve people’s lives. We’re also a company where you can flourish and grow your career, with countless opportunities to explore, make connections with people, and stretch the limits of what you thought was possible. Ready to get started?
Main Responsibilities:
- Contribute to the design of novel and efficient synthetic pathways for drug substances undergoing clinical development
- Conduct and oversee route scouting in laboratory to demonstrate synthetic viability
- Use all imaginable chemistry tools and methods to develop and optimize commercial process for selected drug substance route (photochemistry, biocatalysis, flow chemistry, electrochemistry, on-line analysis/PAT, high-throughput experimentation, structural analysis, computational chemistry, etc.)
- Design, plan and execute experimental plans to optimize reaction, purification and isolation unit operations, guided by technical risk assessments, to deliver safe, efficient, robust and scalable drug substance manufacturing processes that perform reliably at intended scale in batch or continuous format
- Collaborate within project teams by working closely with analytical chemists, process engineers, pilot plant experts and project managers within the CMC Synthetics organization
- Communicate scientific results in a clear, concise, and accurate manner via electronic laboratory notebook documentation, development reports, project discussions and presentations
- Provide concise technical presentations to communicate work to project teams, cross functional teams and management. Document all work on projects and continuous improvements in eLNB experiments and summarize in technical reports
- Establish/extend external network by providing representation and leadership on academic, industrial, or government sponsored collaborations.
- Champion continuous improvements through pursuit of scientific and technical innovations, workflow optimizations, and incorporation of digital tools
About You:
- Ph.D. in organic or synthetic chemistry.
- Knowledge in at least one of the following areas: advanced analytics, flow chemistry, high throughput experimentation.
- Experience in chemocatalysis or biocatalysis including characterization of catalytic processes and/or mechanistic analysis.
- Computational capabilities and basic coding skills.
- Strong publication record in peer-reviewed journals.
- Excellent written and verbal communication skills.
- Ability to operate with flexibility in a dynamic environment and with tight deadlines.
Preferred Qualifications:
- Post-doctoral experience.
- Proficiency with Microsoft suite.
- Familiarity with digital tools (e.g. Scifinder-n, and Reaxys) and advanced data analysis software (e.g. Spotfire).
- Design of experiment, statistical and/or thermo-kinetic modeling.
- Strategic and innovative thinker with a track record of fresh insightful thinking by developing creative approaches to processes and practices.
- French language skills.
Why Choose Us?
- Bring the miracles of science to life alongside a supportive, future-focused team.
- Discover endless opportunities to grow your talent and drive your career, whether it’s through a promotion or lateral move, at home or internationally.
- Enjoy a thoughtful, well-crafted rewards package that recognizes your contribution and amplifies your impact.
Take good care of yourself and your family, with a wide range of health and wellbeing benefits including high-quality healthcare, prevention and wellness programs and at least 14 weeks’ gender-neutral parental leave.
Sanofi Inc. and its U.S. affiliates are Equal Opportunity and Affirmative Action employers committed to a culturally diverse workforce. All qualified applicants will receive consideration for employment without regard to race; color; creed; religion; national origin; age; ancestry; nationality; marital, domestic partnership or civil union status; sex, gender, gender identity or expression; affectional or sexual orientation; disability; veteran or military status or liability for military status; domestic violence victim status; atypical cellular or blood trait; genetic information (including the refusal to submit to genetic testing) or any other characteristic protected by law.
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All compensation will be determined commensurate with demonstrated experience. Employees may be eligible to participate in Company employee benefit programs, and additional benefits information can be found here.
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Pursue Progress. Discover Extraordinary.
Join Sanofi and step into a new era of science - where your growth can be just as transformative as the work we do. We invest in you to reach further, think faster, and do what’s never-been-done-before. You’ll help push boundaries, challenge convention, and build smarter solutions that reach the communities we serve. Ready to chase the miracles of science and improve people’s lives? Let’s Pursue Progress and Discover Extraordinary – together.
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Why work with us
- Expand your horizons. Grow through curiosity, with support to move, learn, and lead in a culture that champions mentorship, mobility, and bold development.
- Accelerate results with technology. Harness the power of AI and automation to push scientific boundaries and reimagine what's possible in drug discovery.
- Impact through inclusive innovation. Help deliver better science and fairer outcomes by driving inclusive research that reaches more people, in more meaningful ways.
- Turn patient needs into breakthrough science. Drive scientific breakthroughs that start with patient needs—and end in treatments that change lives.
Meet Nils Libert, Associate Scientist
Meet Nils Libert, an Associate Scientist in Belgium, where he plays a key role in advancing groundbreaking research. Learn how his work helps drive innovation, uncover new scientific possibilities, and contribute to life-changing treatments that impact patients around the world.

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EVP & Head of R&D
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