Job title: Principal Scientist - Study Lead

• Location: Marcy l’Etoile
• Grade: L3
• Hiring Manager: Lucie ENGELHART

About the job

As Principal Scientist - Study Lead within our Predictive Sciences Platform (Vaccines R&D), you'll lead in vivo studies from design through delivery, while bringing your veterinary and immunology expertise to shape how we develop and evaluate vaccines. Based in Marcy l'Etoile, you'll work at the heart of Sanofi's vaccine R&D organization, collaborating across teams to drive scientific excellence, champion animal welfare, and contribute to the evolution of our in vivo capabilities. Ready to get started? Join the engine of Sanofi's mission — where deep immunoscience meets bold, AI-powered research. In R&D, you'll drive breakthroughs that could turn the impossible into possible for millions.

About Sanofi:

We're an R&D-driven, AI-powered biopharma company committed to improving people's lives and delivering compelling growth. Our deep understanding of the immune system – and innovative pipeline – enables us to invent medicines and vaccines that treat and protect millions of people around the world. Together, we chase the miracles of science to improve people's lives.

Main responsibilities:

• Lead in vivo studies end-to-end — oversee study direction for preclinical vaccine studies across multiple R&D departments, ensuring scientific quality, regulatory compliance, and on-time delivery
• Shape study design — provide immunology and in vivo model expertise during protocol development, helping teams choose the most relevant and efficient experimental approaches
• Drive internalization of studies — bring previously outsourced work in-house, building internal capability and contributing to cost efficiency at the platform level
• Contribute to scientific and ethical review — play a senior role in the Scientific Committee, reviewing in vivo protocols and providing expert input on animal model selection, study optimization, and animal use reduction
• Champion animal welfare — lead Animal Welfare Assessments with CROs, suppliers, and stakeholders, and serve as a reference expert on 3Rs principles and regulatory standards
• Support innovation and continuous improvement — contribute to digitalization of the animal unit, evaluate emerging models and technologies (e.g., organ-on-chip, in silico approaches), and identify opportunities to enhance predictive science methodologies
• Mentor and guide colleagues — support junior scientists and study directors in protocol design, scientific review, and best practices

About you

• Experience: Proven background as a Study Director in a pharmaceutical or biotech R&D environment, with strong expertise in immunology and in vivo preclinical models in the context of vaccine development
• Technical skills: Solid ability to independently design and critically review in vivo protocols; knowledge of animal welfare regulations and 3Rs principles; familiarity with biosafety requirements (Levels 2 and 3); experience with continuous improvement or digitalization projects is a plus
• Soft skills: Strong scientific communication skills; ability to collaborate across multidisciplinary teams and influence decisions without direct authority; proactive and solution-oriented mindset
• Education: DVM (Doctor of Veterinary Medicine) required; a PhD or additional scientific degree is an advantage. Level 1 accreditation "Habilitation à l'expérimentation animale – Niveau concepteur de procédure" (European Directive 2010/63) required
• Languages: Fluent English required (written and spoken); French is an asset given the location

Why choose us?

• Work at the forefront of AI-driven research, smart manufacturing, and groundbreaking mRNA platforms that are redefining the future of immunology.

• Share knowledge with leading scientists, engineers, and experts in a purpose-driven community dedicated to protecting millions worldwide.

• Join a workplace where diversity, equity, and inclusion are at the core, with Employee Resource Groups and leadership programs that celebrate every voice.

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.

At Sanofi, we provide equal opportunities to all regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, protected veteran status or other characteristics protected by law.

Pursue progress, discover extraordinary

Better is out there. Better medications, better outcomes, better science. But progress doesn’t happen without people – people from different backgrounds, in different locations, doing different roles, all united by one thing: a desire to make miracles happen. So, let’s be those people.

At Sanofi, we provide equal opportunities to all regardless of race, colour, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, ability or gender identity.

Watch our ALL IN video and check out our Diversity Equity and Inclusion actions at sanofi.com!