Principal Scientist - Rare Diseases

Job title: Principal Scientist - Rare Diseases Location: Cambridge, MA About the job As Principal Scientist - Rare Diseases within our R&D team, you will join Sanofi's Rare Diseases Research team and lead transformative drug discovery efforts for patients with rare Mendelian disorders. In this role, you will serve as a strategic scientific leader, driving innovation from target identification through clinical candidate selection. This position offers the unique opportunity to shape our rare disease pipeline by leveraging your deep expertise in metabolic disease biology and proven track record of drug discovery. At Sanofi, we are committed to pursuing the miracles of science to improve people's lives. You will translate cutting-edge mechanistic insights into breakthrough therapeutic strategies, working at the intersection of academic innovation and pharmaceutical development. Your leadership will be instrumental in advancing novel treatments for patients with limited or no therapeutic options, including those suffering from inborn errors of metabolism, mitochondrial diseases, and related rare metabolic conditions. 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 Strategic Leadership & Program Direction Build drug discovery programs employing a variety of therapeutic modalities (small molecule, biologics, antisense oligonucleotides, gene therapy, etc.) targeting metabolic and mitochondrial disorders Define research strategy and drive decision-making for rare disease programs from target validation through IND-enabling studies Serve as the scientific voice for programs in governance forums, providing strategic recommendations that shape portfolio priorities Identify and evaluate emerging therapeutic opportunities in metabolic and mitochondrial diseases through competitive intelligence and scientific landscape analysis Scientific Execution & Innovation Design and oversee the execution of sophisticated in vitro and in vivo studies to elucidate disease mechanisms, validate therapeutic targets, and establish proof-of-concept for novel interventions Drive mechanistic understanding of rare metabolic disorders Integrate multi-omics approaches and systems biology to identify disease drivers and therapeutic intervention points Translate preclinical findings into clinical development strategies in collaboration with translational medicine teams Cross-Functional Collaboration & External Partnerships Lead or contribute to cross-functional project teams spanning discovery research, translational medicine, clinical development, and regulatory affairs Build and maintain strategic relationships with leading academic researchers, clinician-scientists, and patient advocacy organizations in the rare metabolic disease community Manage external collaborations including CROs, academic partnerships, and biotech alliances to accelerate program advancement Represent Sanofi's scientific leadership at conferences, advisory boards, and collaborative research forums Scientific Communication & Documentation Generate rigorous data analyses, interpretations, and documentation to support program milestones, regulatory submissions (IND/CTA), patent filings, and publications Communicate complex scientific concepts clearly and persuasively to diverse audiences including senior leadership, external collaborators, and the broader scientific community Mentor and develop junior scientists, fostering a culture of scientific excellence and innovation About You Required Qualifications Ph.D. or equivalent advanced degree in biochemistry, metabolism, mitochondrial biology, molecular/cellular biology, genetics, or related discipline Minimum of 7+ years of post-graduate experience in academic or biopharmaceutical research, with substantial focus on metabolic and/or mitochondrial disorders. Deep expertise in neurological, neuromuscular, and/or mitochondrial disorders Proven drug discovery leadership experience in industry with a track record of contributions to multidisciplinary teams and advancing therapeutic programs toward clinical development Demonstrated contributions to IND/CTA-enabling activities, including target validation, mechanism-of-action studies, biomarker development, and translational research Strong publication record in high-impact journals demonstrating scientific thought leadership in relevant disease areas Preferred Qualifications Established network within the academic, clinical, and patient advocacy communities focused on rare metabolic and mitochondrial diseases Experience with relevant disease models including patient-derived cells, organoids, and animal models Expertise designing and incorporating metabolomics, lipidomics, or other specialized experimental modalities Familiarity with computational biology, bioinformatics, or analysis of large-scale 'omics datasets Experience with multiple therapeutic modalities and platform technologies Prior involvement in regulatory document preparation and interactions with health authorities Understanding of the rare disease drug development landscape, including regulatory pathways and reimbursement considerations Experience presenting at scientific conferences and contributing to the external scientific discourse in rare diseases What You'll Bring Exceptional scientific problem-solving abilities with capacity to integrate complex datasets and drive mechanistic insights Strong experimental design skills with rigorous attention to scientific quality and reproducibility Deep understanding of drug discovery processes from target identification through clinical candidate selection Proven ability to lead, influence, and inspire multidisciplinary teams in a matrixed organization Strategic mindset with capability to balance scientific rigor with business priorities and timelines Outstanding written and verbal communication skills with ability to tailor messages for diverse audiences Why Choose Us Bring the miracles of science to life alongside a supportive, futurefocused 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. Be part of a pioneering biopharma company that engages patients early in drug development and uses their insights to design studies that reflect real-world needs. Work at the forefront of drug discovery, harnessing cutting-edge AI, data, and digital platforms to push the boundaries of science. Help improve the lives of millions of people globally by making drugdevelopment quicker and more effective. 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. #GD-SA #LI-SA #vhd 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! US and Puerto Rico Residents Only Sanofi Inc. and its U.S. affiliates are Equal Opportunity and Affirmative Action employers committed to a culturally inclusive and diverse workforce. All qualified applicants will receive consideration for employment without regard to race; color; creed; religion; national origin; age; ancestry; nationality; natural or protective hairstyles; 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. North America Applicants Only The salary range for this position is: $122,250.00 - $176,583.33 All compensation will be determined commensurate with demonstrated experience. Employees may be eligible to participate in Company employee benefit programs. Additional benefits information can be found through the LINK.