Principal Scientist, In Vivo Pharmacology

Job Title: Principal Scientist, In Vivo Pharmacology

Department: Pharmacology

Reporting to: Senior Director, Pharmacology

Location:  San Diego, CA (Onsite)

About Sirius

Sirius is a clinical stage biotech company developing innovative siRNA therapies for global markets. We are dedicated to discovering and developing new treatment options for cardiovascular and cerebrovascular disease and translating siRNA technology into transformative medicine for the treatment of chronic diseases. Our most advanced products are SRSD107 for the treatment of thromboembolic disorders, SRSD216 for the treatment of hyperlipoproteinemia, and SRSD101 for the treatment of dyslipidemia.

Founded in 2021 by a world-class leadership team and investors, Sirius is dual headquartered in San Diego, where discovery center is located, and Shanghai, where translational medicine and clinical operation center is based. Sirius has raised nearly US$150 million funding to date from top global VC funds such as OrbiMed and Creacion Ventures.

Summary of Position

We are seeking a highly motivated and experienced Principal Scientist to join the Pharmacology team to lead in vivo activities for siRNA drug discovery and development programs. The candidate will lead, design and execute in vivo studies to support preclinical research programs. This role involves leading projects in collaboration with Chemistry and Project Management teams, designing and executing in vivo and ex vivo experiments to assess pharmacodynamics and efficacy of siRNA molecules and generating data to advance pipeline and technology development projects. The ideal candidate is a highly motivated scientist with project leadership experience, hands-on expertise in rodent models in metabolic or renal diseases, strong critical thinking and communication skills, and the ability to collaborate across multidisciplinary teams.

Key Responsibilities

• Provide scientific leadership for in vivo pharmacology activities from target validation through candidate selection.
• Collaborate with In Vitro Pharmacology, Chemistry and Project Management teams to advance pipeline and technology development projects.
• Design and execute in vivo studies including PK/PD, efficacy, and MOA. Analyze and interpret data to enable data-driven decision making.
• Develop translational pharmacology and biomarker strategies. Select and execute in vivo and ex vivo preclinical models to understand MOA, de-risk and optimize lead molecules in support of translational research.
• Develop and implement mouse disease models to expand in house in vivo capability.
• Conduct ex vivo analyses such as RT-qPCR, ELISA, western blot
• Present scientific findings and project updates at research and project team meetings
• Manage collaborations with CROs as needed
• Provide guidance and training to the junior members of the in vivo team
• Stay current with scientific literature and emerging technologies to enhance in vivo research methodologies.
• Maintain accurate documentation of experimental protocols and results in lab notebooks to ensure data integrity.

Qualifications

• PhD in Pharmacology, Physiology, Biology, or a related scientific discipline with 5+ years of relevant experience in pharmaceutical or biotechnology drug discovery.
• Extensive hands-on experience in rodent models with expertise in metabolic or renal diseases is required.
• Experience in leading drug discovery projects, designing and interpreting in vivo pharmacology studies to support target validation, in vivo characterization and candidate selection is required.
• Experience with ex vivo analytical techniques (e.g., ELISA, qPCR, western blot) is required.
• Experience working with external vivarium facilities and managing collaborations with CROs is preferred.
• Excellent verbal and written communication skills.
• Ability to work independently and in a fast-paced, collaborative environment.